Vulkan-Hpp/VulkanHppGenerator.cpp

// Copyright(c) 2015-2020, NVIDIA CORPORATION. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "VulkanHppGenerator.hpp"

#include <algorithm>
#include <cassert>
#include <fstream>
#include <regex>
#include <sstream>

void checkAttributes( int                                                  line,
                      std::map<std::string, std::string> const &           attributes,
                      std::map<std::string, std::set<std::string>> const & required,
                      std::map<std::string, std::set<std::string>> const & optional );
void checkElements( int                                               line,
                    std::vector<tinyxml2::XMLElement const *> const & elements,
                    std::map<std::string, bool> const &               required,
                    std::set<std::string> const &                     optional = {} );
void checkForError( bool condition, int line, std::string const & message );
void checkForWarning( bool condition, int line, std::string const & message );
template <class InputIt, class UnaryPredicate>
std::vector<InputIt>                findAll( InputIt first, InputIt last, UnaryPredicate p );
std::string                         findTag( std::set<std::string> const & tags, std::string const & name, std::string const & postfix = "" );
std::string                         generateCArraySizes( std::vector<std::string> const & sizes );
std::pair<std::string, std::string> generateEnumSuffixes( std::string const & name, bool bitmask, std::set<std::string> const & tags );
std::string generateEnumValueName( std::string const & enumName, std::string const & valueName, bool bitmask, std::set<std::string> const & tags );
std::string generateNamespacedType( std::string const & type );
std::string generateNoDiscard( bool returnsSomething, bool multiSuccessCodes, bool multiErrorCodes );
std::string generateStandardArray( std::string const & type, std::vector<std::string> const & sizes );
std::string generateStandardArrayWrapper( std::string const & type, std::vector<std::string> const & sizes );
std::string generateSuccessCode( std::string const & code, std::set<std::string> const & tags );
std::map<std::string, std::string> getAttributes( tinyxml2::XMLElement const * element );
template <typename ElementContainer>
std::vector<tinyxml2::XMLElement const *>        getChildElements( ElementContainer const * element );
std::pair<std::vector<std::string>, std::string> readModifiers( tinyxml2::XMLNode const * node );
std::string                                      readSnippet( std::string const & snippetFile );
std::string                                      replaceWithMap( std::string const & input, std::map<std::string, std::string> replacements );
std::string                                      startLowerCase( std::string const & input );
std::string                                      startUpperCase( std::string const & input );
std::string                                      stripPostfix( std::string const & value, std::string const & postfix );
std::string                                      stripPluralS( std::string const & name );
std::string                                      stripPrefix( std::string const & value, std::string const & prefix );
std::string                                      toCamelCase( std::string const & value );
std::string                                      toUpperCase( std::string const & name );
std::vector<std::string>                         tokenize( std::string const & tokenString, std::string const & separator );
std::string                                      toString( tinyxml2::XMLError error );
std::string                                      trim( std::string const & input );
std::string                                      trimEnd( std::string const & input );
std::string                                      trimStars( std::string const & input );
void                                             writeToFile( std::string const & str, std::string const & fileName );

const std::set<std::string> altLens             = { "2*VK_UUID_SIZE", "codeSize / 4", "(rasterizationSamples + 31) / 32", "(samples + 31) / 32" };
const std::set<std::string> specialPointerTypes = { "Display", "IDirectFB", "wl_display", "xcb_connection_t", "_screen_window" };

//
// VulkanHppGenerator public interface
//

VulkanHppGenerator::VulkanHppGenerator( tinyxml2::XMLDocument const & document )
{
  // insert the default "handle" without class (for createInstance, and such)
  m_handles.insert( std::make_pair( "", HandleData( {}, "", false, 0 ) ) );

  // read the document and check its correctness
  int                                       line     = document.GetLineNum();
  std::vector<tinyxml2::XMLElement const *> elements = getChildElements( &document );
  checkElements( line, elements, { { "registry", true } } );
  checkForError( elements.size() == 1, line, "encountered " + std::to_string( elements.size() ) + " elements named <registry> but only one is allowed" );
  readRegistry( elements[0] );
  checkCorrectness();

  // some "FlagBits" enums are not specified, but needed for our "Flags" handling -> add them here
  for ( auto & feature : m_features )
  {
    addMissingFlagBits( feature.second.requireData, feature.first );
  }
  for ( auto & extension : m_extensions )
  {
    addMissingFlagBits( extension.second.requireData, extension.first );
  }

  // determine the extensionsByNumber map
  for ( auto extensionIt = m_extensions.begin(); extensionIt != m_extensions.end(); ++extensionIt )
  {
    int number = stoi( extensionIt->second.number );
    assert( m_extensionsByNumber.find( number ) == m_extensionsByNumber.end() );
    m_extensionsByNumber[number] = extensionIt;
  }
}

void VulkanHppGenerator::generateVulkanEnumsHppFile() const
{
  std::string const vulkan_enums_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_enums.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_enums_hpp << " ..." << std::endl;

  std::string const vulkanEnumsHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_ENUMS_HPP
#  define VULKAN_ENUMS_HPP

namespace VULKAN_HPP_NAMESPACE
{
  template <typename EnumType, EnumType value>
  struct CppType
  {};

  template <typename Type>
  struct isVulkanHandleType
  {
    static VULKAN_HPP_CONST_OR_CONSTEXPR bool value = false;
  };
${enums}
${indexTypeTraits}
${bitmasks}
}   // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str = replaceWithMap( vulkanEnumsHppTemplate,
                                    { { "bitmasks", generateBitmasks() },
                                      { "enums", generateEnums() },
                                      { "indexTypeTraits", generateIndexTypeTraits() },
                                      { "licenseHeader", m_vulkanLicenseHeader } } );

  writeToFile( str, vulkan_enums_hpp );
}

void VulkanHppGenerator::generateVulkanFormatTraitsHppFile() const
{
  std::string const vulkan_format_traits_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_format_traits.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_format_traits_hpp << " ..." << std::endl;

  std::string const vulkanFormatTraitsHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_FORMAT_TRAITS_HPP
#  define VULKAN_FORMAT_TRAITS_HPP

#include <vulkan/vulkan.hpp>

namespace VULKAN_HPP_NAMESPACE
{
${formatTraits}
}   // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str = replaceWithMap( vulkanFormatTraitsHppTemplate, { { "formatTraits", generateFormatTraits() }, { "licenseHeader", m_vulkanLicenseHeader } } );

  writeToFile( str, vulkan_format_traits_hpp );
}

void VulkanHppGenerator::generateVulkanFuncsHppFile() const
{
  std::string const vulkan_funcs_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_funcs.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_funcs_hpp << " ..." << std::endl;

  std::string const vulkanFuncsHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_FUNCS_HPP
#  define VULKAN_FUNCS_HPP

namespace VULKAN_HPP_NAMESPACE
{
${commandDefinitions}
  }   // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str =
    replaceWithMap( vulkanFuncsHppTemplate, { { "commandDefinitions", generateCommandDefinitions() }, { "licenseHeader", m_vulkanLicenseHeader } } );

  writeToFile( str, vulkan_funcs_hpp );
}

void VulkanHppGenerator::generateVulkanHandlesHppFile() const
{
  std::string const vulkan_handles_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_handles.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_handles_hpp << " ..." << std::endl;

  std::string const vulkanHandlesHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_HANDLES_HPP
#  define VULKAN_HANDLES_HPP

namespace VULKAN_HPP_NAMESPACE
{
${structForwardDeclarations}
${handles}
  }   // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str = replaceWithMap(
    vulkanHandlesHppTemplate,
    { { "handles", generateHandles() }, { "licenseHeader", m_vulkanLicenseHeader }, { "structForwardDeclarations", generateStructForwardDeclarations() } } );

  writeToFile( str, vulkan_handles_hpp );
}

void VulkanHppGenerator::generateVulkanHashHppFile() const
{
  std::string const vulkan_hash_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_hash.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_hash_hpp << " ..." << std::endl;

  std::string const vulkanHandlesHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_HASH_HPP
#  define VULKAN_HASH_HPP

#include <vulkan/vulkan.hpp>

namespace std
{
  //=======================================
  //=== HASH structures for Flags types ===
  //=======================================

  template <typename BitType>
  struct hash<VULKAN_HPP_NAMESPACE::Flags<BitType>>
  {
    std::size_t operator()( VULKAN_HPP_NAMESPACE::Flags<BitType> const & flags ) const VULKAN_HPP_NOEXCEPT
    {
      return std::hash<typename std::underlying_type<BitType>::type>{}(
        static_cast<typename std::underlying_type<BitType>::type>( flags ) );
    }
  };

${handleHashStructures}
${structHashStructures}
} // namespace std
#endif
)";

  std::string str = replaceWithMap( vulkanHandlesHppTemplate,
                                    { { "handleHashStructures", generateHandleHashStructures() },
                                      { "licenseHeader", m_vulkanLicenseHeader },
                                      { "structHashStructures", generateStructHashStructures() } } );

  writeToFile( str, vulkan_hash_hpp );
}

void VulkanHppGenerator::generateVulkanHppFile() const
{
  std::string const vulkan_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_hpp << " ... " << std::endl;

  std::string const vulkanHppTemplate = R"(${licenseHeader}
${includes}

static_assert( VK_HEADER_VERSION == ${headerVersion}, "Wrong VK_HEADER_VERSION!" );

// 32-bit vulkan is not typesafe for non-dispatchable handles, so don't allow copy constructors on this platform by default.
// To enable this feature on 32-bit platforms please define VULKAN_HPP_TYPESAFE_CONVERSION
${typesafeCheck}
#  if !defined( VULKAN_HPP_TYPESAFE_CONVERSION )
#    define VULKAN_HPP_TYPESAFE_CONVERSION
#  endif
#endif

${defines}

namespace VULKAN_HPP_NAMESPACE
{
${ArrayWrapper1D}
${ArrayWrapper2D}
${Flags}
#if !defined( VULKAN_HPP_DISABLE_ENHANCED_MODE )
${ArrayProxy}
${ArrayProxyNoTemporaries}
${StridedArrayProxy}
${Optional}
${StructureChain}
${UniqueHandle}
#endif  // VULKAN_HPP_DISABLE_ENHANCED_MODE

${DispatchLoaderBase}
${DispatchLoaderStatic}
${DispatchLoaderDefault}
#if !defined( VULKAN_HPP_NO_SMART_HANDLE )
${ObjectDestroy}
${ObjectFree}
${ObjectRelease}
${PoolFree}
#endif // !VULKAN_HPP_NO_SMART_HANDLE
${baseTypes}
} // namespace VULKAN_HPP_NAMESPACE

#include <vulkan/vulkan_enums.hpp>
#if !defined( VULKAN_HPP_NO_TO_STRING )
#include <vulkan/vulkan_to_string.hpp>
#endif

#ifndef VULKAN_HPP_NO_EXCEPTIONS
namespace std
{
  template <>
  struct is_error_code_enum<VULKAN_HPP_NAMESPACE::Result> : public true_type
  {};
}  // namespace std
#endif

namespace VULKAN_HPP_NAMESPACE
{
#ifndef VULKAN_HPP_NO_EXCEPTIONS
${Exceptions}
${resultExceptions}
${throwResultException}
#endif

${ResultValue}
${resultChecks}
} // namespace VULKAN_HPP_NAMESPACE

// clang-format off
#include <vulkan/vulkan_handles.hpp>
#include <vulkan/vulkan_structs.hpp>
#include <vulkan/vulkan_funcs.hpp>
// clang-format on

namespace VULKAN_HPP_NAMESPACE
{
#if !defined( VULKAN_HPP_DISABLE_ENHANCED_MODE )
${structExtendsStructs}
#endif // VULKAN_HPP_DISABLE_ENHANCED_MODE

${DynamicLoader}
${DispatchLoaderDynamic}
}   // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str = replaceWithMap( vulkanHppTemplate,
                                    { { "ArrayProxy", readSnippet( "ArrayProxy.hpp" ) },
                                      { "ArrayProxyNoTemporaries", readSnippet( "ArrayProxyNoTemporaries.hpp" ) },
                                      { "ArrayWrapper1D", readSnippet( "ArrayWrapper1D.hpp" ) },
                                      { "ArrayWrapper2D", readSnippet( "ArrayWrapper2D.hpp" ) },
                                      { "baseTypes", generateBaseTypes() },
                                      { "defines", readSnippet( "defines.hpp" ) },
                                      { "DispatchLoaderBase", readSnippet( "DispatchLoaderBase.hpp" ) },
                                      { "DispatchLoaderDefault", readSnippet( "DispatchLoaderDefault.hpp" ) },
                                      { "DispatchLoaderDynamic", generateDispatchLoaderDynamic() },
                                      { "DispatchLoaderStatic", generateDispatchLoaderStatic() },
                                      { "DynamicLoader", readSnippet( "DynamicLoader.hpp" ) },
                                      { "Exceptions", readSnippet( "Exceptions.hpp" ) },
                                      { "Flags", readSnippet( "Flags.hpp" ) },
                                      { "headerVersion", m_version },
                                      { "includes", readSnippet( "includes.hpp" ) },
                                      { "licenseHeader", m_vulkanLicenseHeader },
                                      { "ObjectDestroy", readSnippet( "ObjectDestroy.hpp" ) },
                                      { "ObjectFree", readSnippet( "ObjectFree.hpp" ) },
                                      { "ObjectRelease", readSnippet( "ObjectRelease.hpp" ) },
                                      { "Optional", readSnippet( "Optional.hpp" ) },
                                      { "PoolFree", readSnippet( "PoolFree.hpp" ) },
                                      { "resultChecks", readSnippet( "resultChecks.hpp" ) },
                                      { "resultExceptions", generateResultExceptions() },
                                      { "structExtendsStructs", generateStructExtendsStructs() },
                                      { "ResultValue", readSnippet( "ResultValue.hpp" ) },
                                      { "StridedArrayProxy", readSnippet( "StridedArrayProxy.hpp" ) },
                                      { "StructureChain", readSnippet( "StructureChain.hpp" ) },
                                      { "throwResultException", generateThrowResultException() },
                                      { "typesafeCheck", m_typesafeCheck },
                                      { "UniqueHandle", readSnippet( "UniqueHandle.hpp" ) } } );

  writeToFile( str, vulkan_hpp );
}

void VulkanHppGenerator::generateVulkanRAIIHppFile() const
{
  std::string const vulkan_raii_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_raii.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_raii_hpp << " ..." << std::endl;

  std::string const vulkanHandlesHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_RAII_HPP
#  define VULKAN_RAII_HPP

#include <memory>
#include <utility>  // std::exchange, std::forward
#include <vulkan/vulkan.hpp>

#if !defined( VULKAN_HPP_RAII_NAMESPACE )
#  define VULKAN_HPP_RAII_NAMESPACE raii
#endif

namespace VULKAN_HPP_NAMESPACE
{
  namespace VULKAN_HPP_RAII_NAMESPACE
  {
#if !defined( VULKAN_HPP_DISABLE_ENHANCED_MODE ) && !defined(VULKAN_HPP_NO_EXCEPTIONS)

    template <class T, class U = T>
    VULKAN_HPP_CONSTEXPR_14 VULKAN_HPP_INLINE T exchange( T & obj, U && newValue )
    {
#  if ( 14 <= VULKAN_HPP_CPP_VERSION )
      return std::exchange<T>( obj, std::forward<U>( newValue ) );
#  else
      T oldValue = std::move( obj );
      obj        = std::forward<U>( newValue );
      return oldValue;
#  endif
    }

${RAIIDispatchers}
${RAIIHandles}
${RAIICommandDefinitions}
#endif
  } // namespace VULKAN_HPP_RAII_NAMESPACE
}   // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str = replaceWithMap( vulkanHandlesHppTemplate,
                                    { { "licenseHeader", m_vulkanLicenseHeader },
                                      { "RAIICommandDefinitions", generateRAIICommandDefinitions() },
                                      { "RAIIDispatchers", generateRAIIDispatchers() },
                                      { "RAIIHandles", generateRAIIHandles() } } );

  writeToFile( str, vulkan_raii_hpp );
}

void VulkanHppGenerator::generateVulkanStaticAssertionsHppFile() const
{
  std::string const static_assertions_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_static_assertions.hpp";
  std::cout << "VulkanHppGenerator: Generating " << static_assertions_hpp << " ..." << std::endl;

  std::string const vulkanHandlesHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_STRUCTS_HPP
#  define VULKAN_STRUCTS_HPP

#include <vulkan/vulkan.hpp>

//=========================
//=== static_assertions ===
//=========================

${staticAssertions}
#endif
)";

  std::string str =
    replaceWithMap( vulkanHandlesHppTemplate, { { "licenseHeader", m_vulkanLicenseHeader }, { "staticAssertions", generateStaticAssertions() } } );

  writeToFile( str, static_assertions_hpp );
}

void VulkanHppGenerator::generateVulkanStructsHppFile() const
{
  std::string const vulkan_structs_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_structs.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_structs_hpp << " ..." << std::endl;

  std::string const vulkanHandlesHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_STRUCTS_HPP
#  define VULKAN_STRUCTS_HPP

#include <cstring>  // strcmp

namespace VULKAN_HPP_NAMESPACE
{
${structs}
}   // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str = replaceWithMap( vulkanHandlesHppTemplate, { { "licenseHeader", m_vulkanLicenseHeader }, { "structs", generateStructs() } } );

  writeToFile( str, vulkan_structs_hpp );
}

void VulkanHppGenerator::generateVulkanToStringHppFile() const
{
  std::string const vulkan_to_string_hpp = std::string( BASE_PATH ) + "/vulkan/vulkan_to_string.hpp";
  std::cout << "VulkanHppGenerator: Generating " << vulkan_to_string_hpp << "..." << std::endl;

  std::string const vulkanHandlesHppTemplate = R"(${licenseHeader}
#ifndef VULKAN_TO_STRING_HPP
#  define VULKAN_TO_STRING_HPP

#include <vulkan/vulkan_enums.hpp>

#if __cpp_lib_format
#  include <format>   // std::format
#else
#  include <sstream>  // std::stringstream
#endif

namespace VULKAN_HPP_NAMESPACE
{
${bitmasksToString}
${enumsToString}
} // namespace VULKAN_HPP_NAMESPACE
#endif
)";

  std::string str = replaceWithMap(
    vulkanHandlesHppTemplate,
    { { "bitmasksToString", generateBitmasksToString() }, { "enumsToString", generateEnumsToString() }, { "licenseHeader", m_vulkanLicenseHeader } } );

  writeToFile( str, vulkan_to_string_hpp );
}

void VulkanHppGenerator::prepareRAIIHandles()
{
  // filter out functions that are not usefull on this level of abstraction (like vkGetInstanceProcAddr)
  // and all the construction and destruction functions, as they are used differently
  assert( m_handles.begin()->first.empty() );
  for ( auto handleIt = std::next( m_handles.begin() ); handleIt != m_handles.end(); ++handleIt )
  {
    handleIt->second.destructorIt = determineRAIIHandleDestructor( handleIt->first );
    if ( handleIt->second.destructorIt != m_commands.end() )
    {
      m_RAIISpecialFunctions.insert( handleIt->second.destructorIt->first );
    }
    handleIt->second.constructorIts = determineRAIIHandleConstructors( handleIt->first, handleIt->second.destructorIt );
  }

  distributeSecondLevelCommands( m_RAIISpecialFunctions );

  // we rename a couple of function parameters to prevent this warning, treated as an error:
  // warning C4458: declaration of 'objectType' hides class member
  for ( auto & command : m_commands )
  {
    for ( auto & param : command.second.params )
    {
      if ( param.name == "objectType" )
      {
        param.name += "_";
      }
    }
  }
}

//
// VulkanHppGenerator private interface
//

void VulkanHppGenerator::addCommand( std::string const & name, CommandData & commandData )
{
  // find the handle this command is going to be associated to
  checkForError( !commandData.params.empty(), commandData.xmlLine, "command <" + name + "> with no params" );
  std::map<std::string, HandleData>::iterator handleIt = m_handles.find( commandData.params[0].type.type );
  if ( handleIt == m_handles.end() )
  {
    handleIt = m_handles.find( "" );
  }
  assert( handleIt != m_handles.end() );
  commandData.handle = handleIt->first;

  // add this command to the list of commands
  checkForError( m_commands.insert( std::make_pair( name, commandData ) ).second, commandData.xmlLine, "already encountered command <" + name + ">" );

  // put the command into the handle's list of commands
  checkForError( handleIt->second.commands.insert( name ).second,
                 commandData.xmlLine,
                 "command list of handle <" + handleIt->first + "> already holds a commnand <" + name + ">" );
}

void VulkanHppGenerator::addMissingFlagBits( std::vector<RequireData> & requireData, std::string const & referencedIn )
{
  for ( auto & require : requireData )
  {
    std::vector<std::string> newTypes;
    for ( auto const & type : require.types )
    {
      auto bitmaskIt = m_bitmasks.find( type );
      if ( ( bitmaskIt != m_bitmasks.end() ) && bitmaskIt->second.requirements.empty() )
      {
        // generate the flagBits enum name out of the bitmask name: VkFooFlagsXXX -> VkFooFlagBitsXXX
        size_t pos = bitmaskIt->first.find( "Flags" );
        assert( pos != std::string::npos );
        std::string flagBits = bitmaskIt->first.substr( 0, pos + 4 ) + "Bit" + bitmaskIt->first.substr( pos + 4 );

        // as the bitmask's requirement is still empty, this flagBits should not be listed in the require list!
        assert( std::find_if( require.types.begin(), require.types.end(), [&flagBits]( std::string const & type ) { return ( type == flagBits ); } ) ==
                require.types.end() );

        bitmaskIt->second.requirements = flagBits;

        // some flagsBits are specified but never listed as required for any flags!
        // so, even if this bitmask has no enum listed as required, it might still already exist in the enums list
        if ( m_enums.find( flagBits ) == m_enums.end() )
        {
          m_enums.insert( std::make_pair( flagBits, EnumData( 0, true ) ) );

          assert( m_types.find( flagBits ) == m_types.end() );
          m_types.insert( std::make_pair( flagBits, TypeData( TypeCategory::Bitmask, referencedIn ) ) );
        }
        else
        {
          assert( m_types.find( flagBits ) != m_types.end() );
        }

        newTypes.push_back( flagBits );
      }
    }
    // add all the newly created flagBits types to the require list as if they had been part of the vk.xml!
    require.types.insert( require.types.end(), newTypes.begin(), newTypes.end() );
  }
}

std::string VulkanHppGenerator::addTitleAndProtection( std::string const & title, std::string const & strIf, std::string const & strElse ) const
{
  std::string str;
  if ( !strIf.empty() )
  {
    auto [enter, leave] = generateProtection( title, std::string() );
    str                 = "\n" + enter + "  //=== " + title + " ===\n" + strIf;
    if ( !enter.empty() && !strElse.empty() )
    {
      str += "#else \n" + strElse;
    }
    str += leave;
  }
  return str;
}

bool VulkanHppGenerator::allVectorSizesSupported( std::vector<ParamData> const & params, std::map<size_t, VectorParamData> const & vectorParams ) const
{
  // check if all vector sizes are by value and their type is one of "uint32_t", "VkDeviceSize", or "VkSampleCountFlagBits"
  return std::find_if_not( vectorParams.begin(),
                           vectorParams.end(),
                           [&params]( auto const & vpi )
                           {
                             return params[vpi.second.lenParam].type.isValue() &&
                                    ( ( params[vpi.second.lenParam].type.type == "uint32_t" ) || ( params[vpi.second.lenParam].type.type == "VkDeviceSize" ) ||
                                      ( params[vpi.second.lenParam].type.type == "VkSampleCountFlagBits" ) );
                           } ) == vectorParams.end();
}

void VulkanHppGenerator::appendDispatchLoaderDynamicCommands( std::vector<RequireData> const & requireData,
                                                              std::set<std::string> &          listedCommands,
                                                              std::string const &              title,
                                                              std::string &                    commandMembers,
                                                              std::string &                    initialCommandAssignments,
                                                              std::string &                    instanceCommandAssignments,
                                                              std::string &                    deviceCommandAssignments ) const
{
  std::string members, initial, instance, device, placeholders;
  for ( auto const & require : requireData )
  {
    for ( auto const & command : require.commands )
    {
      if ( listedCommands.insert( command ).second )
      {
        auto commandIt = m_commands.find( command );
        assert( commandIt != m_commands.end() );

        members += "    PFN_" + commandIt->first + " " + commandIt->first + " = 0;\n";
        placeholders += "    PFN_dummy " + commandIt->first + "_placeholder = 0;\n";
        if ( commandIt->second.handle.empty() )
        {
          initial += generateDispatchLoaderDynamicCommandAssignment( commandIt->first, commandIt->second, "NULL" );
        }
        else
        {
          instance += generateDispatchLoaderDynamicCommandAssignment( commandIt->first, commandIt->second, "instance" );
          if ( isDeviceCommand( commandIt->second ) )
          {
            device += generateDispatchLoaderDynamicCommandAssignment( commandIt->first, commandIt->second, "device" );
          }
        }
      }
    }
  }
  auto [enter, leave] = generateProtection( title, std::string() );
  std::string header  = "\n" + enter + "  //=== " + title + " ===\n";
  if ( !members.empty() )
  {
    commandMembers += header + members;
    if ( !enter.empty() )
    {
      commandMembers += "#else\n" + placeholders;
    }
    commandMembers += leave;
  }
  if ( !initial.empty() )
  {
    initialCommandAssignments += header + initial + leave;
  }
  if ( !instance.empty() )
  {
    instanceCommandAssignments += header + instance + leave;
  }
  if ( !device.empty() )
  {
    deviceCommandAssignments += header + device + leave;
  }
}

void VulkanHppGenerator::appendRAIIDispatcherCommands( std::vector<RequireData> const & requireData,
                                                       std::set<std::string> &          listedCommands,
                                                       std::string const &              title,
                                                       std::string &                    contextInitializers,
                                                       std::string &                    contextMembers,
                                                       std::string &                    deviceAssignments,
                                                       std::string &                    deviceMembers,
                                                       std::string &                    instanceAssignments,
                                                       std::string &                    instanceMembers ) const
{
  std::string ci, cm, da, dm, dmp, ia, im, imp;
  for ( auto const & require : requireData )
  {
    for ( auto const & command : require.commands )
    {
      if ( listedCommands.insert( command ).second )
      {
        auto commandIt = m_commands.find( command );
        assert( commandIt != m_commands.end() );
        if ( commandIt->second.handle.empty() )
        {
          assert( commandIt->second.alias.empty() );

          ci += ", " + commandIt->first + "( PFN_" + commandIt->first + "( getProcAddr( NULL, \"" + commandIt->first + "\" ) ) )";

          cm += "      PFN_" + commandIt->first + " " + commandIt->first + " = 0;\n";
        }
        else if ( ( commandIt->second.handle == "VkDevice" ) || hasParentHandle( commandIt->second.handle, "VkDevice" ) )
        {
          da += "        " + commandIt->first + " = PFN_" + commandIt->first + "( vkGetDeviceProcAddr( device, \"" + commandIt->first + "\" ) );\n";
          // if this is an alias'ed function, use it as a fallback for the original one
          if ( !commandIt->second.alias.empty() )
          {
            da += "        if ( !" + commandIt->second.alias + " ) " + commandIt->second.alias + " = " + commandIt->first + ";\n";
          }

          dm += "      PFN_" + commandIt->first + " " + commandIt->first + " = 0;\n";
          dmp += "      PFN_dummy " + commandIt->first + "_placeholder = 0;\n";
        }
        else
        {
          assert( ( commandIt->second.handle == "VkInstance" ) || hasParentHandle( commandIt->second.handle, "VkInstance" ) );

          // filter out vkGetInstanceProcAddr, as starting with Vulkan 1.2 it can resolve itself only (!) with an
          // instance nullptr !
          if ( command != "vkGetInstanceProcAddr" )
          {
            ia += "        " + commandIt->first + " = PFN_" + commandIt->first + "( vkGetInstanceProcAddr( instance, \"" + commandIt->first + "\" ) );\n";
            // if this is an alias'ed function, use it as a fallback for the original one
            if ( !commandIt->second.alias.empty() )
            {
              ia += "        if ( !" + commandIt->second.alias + " ) " + commandIt->second.alias + " = " + commandIt->first + ";\n";
            }
          }

          im += +"      PFN_" + commandIt->first + " " + commandIt->first + " = 0;\n";
          imp += "      PFN_dummy " + commandIt->first + "_placeholder = 0;\n";
        }
      }
    }
  }
  contextInitializers += addTitleAndProtection( title, ci );
  contextMembers += addTitleAndProtection( title, cm );
  deviceAssignments += addTitleAndProtection( title, da );
  deviceMembers += addTitleAndProtection( title, dm, dmp );
  instanceAssignments += addTitleAndProtection( title, ia );
  instanceMembers += addTitleAndProtection( title, im, imp );
}

void VulkanHppGenerator::checkBitmaskCorrectness() const
{
  for ( auto const & bitmask : m_bitmasks )
  {
    // check that a bitmask is referenced somewhere
    // I think, it's not forbidden to not reference a bitmask, but it would probably be not intended?
    auto typeIt = m_types.find( bitmask.first );
    assert( typeIt != m_types.end() );
    checkForError( !typeIt->second.referencedIn.empty(), bitmask.second.xmlLine, "bitmask <" + bitmask.first + "> not listed in any feature or extension" );

    // check that the requirement is an enum
    if ( !bitmask.second.requirements.empty() )
    {
      checkForError( m_enums.find( bitmask.second.requirements ) != m_enums.end(),
                     bitmask.second.xmlLine,
                     "bitmask requires unknown <" + bitmask.second.requirements + ">" );
    }
  }
}

void VulkanHppGenerator::checkCommandCorrectness() const
{
  // prepare command checks by gathering all result codes and aliases into one set of resultCodes
  auto resultIt = m_enums.find( "VkResult" );
  assert( resultIt != m_enums.end() );
  std::set<std::string> resultCodes;
  for ( auto rc : resultIt->second.values )
  {
    resultCodes.insert( rc.name );
  }
  for ( auto rc : resultIt->second.aliases )
  {
    resultCodes.insert( rc.first );
  }

  // command checks
  for ( auto const & command : m_commands )
  {
    // check that a command is referenced somewhere
    // I think, it's not forbidden to not reference a function, but it would probably be not intended?
    checkForError( !command.second.referencedIn.empty(), command.second.xmlLine, "command <" + command.first + "> not listed in any feature or extension" );

    // check for unknow error or succes codes
    for ( auto const & ec : command.second.errorCodes )
    {
      checkForError( resultCodes.find( ec ) != resultCodes.end(), command.second.xmlLine, "command uses unknown error code <" + ec + ">" );
    }
    for ( auto const & sc : command.second.successCodes )
    {
      checkForError( resultCodes.find( sc ) != resultCodes.end(), command.second.xmlLine, "command uses unknown success code <" + sc + ">" );
    }

    // check that functions returning a VkResult specify successcodes
    checkForError( ( command.second.returnType != "VkResult" ) || !command.second.successCodes.empty(),
                   command.second.xmlLine,
                   "missing successcodes on command <" + command.first + "> returning VkResult!" );

    // check that all parameter types as well as the return type are known types
    for ( auto const & p : command.second.params )
    {
      checkForError( m_types.find( p.type.type ) != m_types.end(), p.xmlLine, "comand uses parameter of unknown type <" + p.type.type + ">" );
    }
    checkForError( m_types.find( command.second.returnType ) != m_types.end(),
                   command.second.xmlLine,
                   "command uses unknown return type <" + command.second.returnType + ">" );
  }
}

void VulkanHppGenerator::checkCorrectness() const
{
  checkForError( !m_vulkanLicenseHeader.empty(), -1, "missing license header" );
  checkBitmaskCorrectness();
  checkCommandCorrectness();
  checkEnumCorrectness();
  checkExtensionCorrectness();
  checkFuncPointerCorrectness();
  checkHandleCorrectness();
  checkStructCorrectness();
}

void VulkanHppGenerator::checkEnumCorrectness() const
{
  for ( auto const & e : m_enums )
  {
    // check that a bitmask is referenced somewhere
    // it's not forbidden to not reference a bitmask, and in fact that happens! So just warn here
    auto typeIt = m_types.find( e.first );
    assert( typeIt != m_types.end() );
    checkForWarning( !typeIt->second.referencedIn.empty(), e.second.xmlLine, "enum <" + e.first + "> not listed in any feature or extension" );

    // check that the aliasNames are known enum values or known aliases
    for ( auto const & alias : e.second.aliases )
    {
      checkForError(
        ( std::find_if( e.second.values.begin(), e.second.values.end(), [&alias]( EnumValueData const & evd ) { return evd.name == alias.second.name; } ) !=
          e.second.values.end() ) ||
          ( e.second.aliases.find( alias.second.name ) != e.second.aliases.end() ),
        alias.second.xmlLine,
        "enum <" + alias.first + "> uses unknown alias <" + alias.second.name + ">" );
    }

    // check that any protection fits to the corresponding extension
    for ( auto const & v : e.second.values )
    {
      if ( !v.protect.empty() )
      {
        auto extIt = m_extensions.find( v.extension );
        assert( extIt != m_extensions.end() );
        auto platformIt = m_platforms.find( extIt->second.platform );
        assert( platformIt != m_platforms.end() );
        checkForError( v.protect == platformIt->second.protect,
                       v.xmlLine,
                       "attribute <protect> of enum value <" + v.name + "> is \"" + v.protect + "\" but corresponding extension <" + v.extension +
                         "> belongs to platform <" + platformIt->first + "> with protection \"" + platformIt->second.protect + "\"" );
      }
    }
  }

  // enum checks by features and extensions
  for ( auto & feature : m_features )
  {
    checkEnumCorrectness( feature.second.requireData );
  }
  for ( auto & ext : m_extensions )
  {
    checkEnumCorrectness( ext.second.requireData );
  }

  // special check for VkFormat
  if ( !m_formats.empty() )
  {
    auto enumIt = m_enums.find( "VkFormat" );
    assert( enumIt != m_enums.end() );
    assert( enumIt->second.values.front().name == "VK_FORMAT_UNDEFINED" );
    for ( auto enumValueIt = std::next( enumIt->second.values.begin() ); enumValueIt != enumIt->second.values.end(); ++enumValueIt )
    {
      auto formatIt = m_formats.find( enumValueIt->name );
      if ( formatIt == m_formats.end() )
      {
        auto aliasIt = std::find_if(
          enumIt->second.aliases.begin(), enumIt->second.aliases.end(), [&enumValueIt]( auto const & ead ) { return ead.second.name == enumValueIt->name; } );
        checkForError( aliasIt != enumIt->second.aliases.end(), enumValueIt->xmlLine, "missing format specification for <" + enumValueIt->name + ">" );
      }
    }
  }
}

void VulkanHppGenerator::checkEnumCorrectness( std::vector<RequireData> const & requireData ) const
{
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto typeIt = m_types.find( type );
      assert( typeIt != m_types.end() );
      switch ( typeIt->second.category )
      {
        case TypeCategory::Bitmask:
          {
            // check that each "require" listed for a bitmask is listed for a feature or an extension
            auto bitmaskIt = m_bitmasks.find( type );
            if ( bitmaskIt != m_bitmasks.end() )
            {
              // not for every bitmask is a "require" listed
              if ( !bitmaskIt->second.requirements.empty() )
              {
                auto requireTypeIt = m_types.find( bitmaskIt->second.requirements );
                assert( requireTypeIt != m_types.end() );
                checkForError( !requireTypeIt->second.referencedIn.empty(),
                               bitmaskIt->second.xmlLine,
                               "bitmask <" + bitmaskIt->first + "> requires <" + bitmaskIt->second.requirements +
                                 "> which is not listed for any feature or extension!" );
              }
            }
            else
            {
              // every bitmask not listed in the m_bitmasks, should be an alias of such a thing
              assert( std::find_if( m_bitmasks.begin(),
                                    m_bitmasks.end(),
                                    [&type]( std::pair<const std::string, BitmaskData> const & bd ) { return bd.second.alias == type; } ) != m_bitmasks.end() );
            }
          }
          break;
        case TypeCategory::Enum:
          {
            auto enumIt = m_enums.find( type );
            if ( enumIt != m_enums.end() )
            {
              if ( enumIt->second.isBitmask )
              {
                // check that any enum of a bitmask is listed as "require" or "bitvalues" for a bitmask
                auto bitmaskIt = std::find_if(
                  m_bitmasks.begin(), m_bitmasks.end(), [&enumIt]( auto const & bitmask ) { return bitmask.second.requirements == enumIt->first; } );
                checkForError( bitmaskIt != m_bitmasks.end(),
                               enumIt->second.xmlLine,
                               "enum <" + enumIt->first + "> is not listed as an requires or bitvalues for any bitmask in the types section" );

                // check that bitwidth of the enum and type of the corresponding bitmask are equal
                checkForError( ( enumIt->second.bitwidth != "64" ) || ( bitmaskIt->second.type == "VkFlags64" ),
                               enumIt->second.xmlLine,
                               "enum <" + enumIt->first + "> is marked with bitwidth <64> but corresponding bitmask <" + bitmaskIt->first +
                                 "> is not of type <VkFlags64>" );
              }
            }
            else
            {
              // every enum not listed in the m_enums, should be an alias of such a thing
              assert( std::find_if( m_enums.begin(),
                                    m_enums.end(),
                                    [&type]( std::pair<const std::string, EnumData> const & ed ) { return ed.second.alias == type; } ) != m_enums.end() );
            }
          }
          break;
        default: break;
      }
    }
  }
}

bool VulkanHppGenerator::checkEquivalentSingularConstructor( std::vector<std::map<std::string, CommandData>::const_iterator> const & constructorIts,
                                                             std::map<std::string, CommandData>::const_iterator                      constructorIt,
                                                             std::vector<ParamData>::const_iterator                                  lenIt ) const
{
  // check, if there is no singular constructor with the very same arguments as this array constructor
  // (besides the size, of course)
  auto isEquivalentSingularConstructor = [constructorIt, lenIt]( std::map<std::string, CommandData>::const_iterator it )
  {
    if ( it->second.params.size() + 1 != constructorIt->second.params.size() )
    {
      return false;
    }
    size_t lenIdx = std::distance( constructorIt->second.params.begin(), lenIt );
    for ( size_t i = 0, j = 0; i < it->second.params.size(); ++i, ++j )
    {
      assert( j < constructorIt->second.params.size() );
      if ( j == lenIdx )
      {
        ++j;
      }
      if ( it->second.params[i].type.type != constructorIt->second.params[j].type.type )
      {
        return false;
      }
    }
    return true;
  };
  return ( std::find_if( constructorIts.begin(), constructorIts.end(), isEquivalentSingularConstructor ) != constructorIts.end() );
}

void VulkanHppGenerator::checkExtensionCorrectness() const
{
  for ( auto const & extension : m_extensions )
  {
    // check for existence of any deprecation, obsoletion, or promotion
    if ( !extension.second.deprecatedBy.empty() )
    {
      checkForError( ( m_extensions.find( extension.second.deprecatedBy ) != m_extensions.end() ) ||
                       ( m_features.find( extension.second.deprecatedBy ) != m_features.end() ),
                     extension.second.xmlLine,
                     "extension deprecated by unknown extension/version <" + extension.second.promotedTo + ">" );
    }
    if ( !extension.second.obsoletedBy.empty() )
    {
      checkForError( ( m_extensions.find( extension.second.obsoletedBy ) != m_extensions.end() ) ||
                       ( m_features.find( extension.second.obsoletedBy ) != m_features.end() ),
                     extension.second.xmlLine,
                     "extension obsoleted by unknown extension/version <" + extension.second.promotedTo + ">" );
    }
    if ( !extension.second.promotedTo.empty() )
    {
      checkForError( ( m_extensions.find( extension.second.promotedTo ) != m_extensions.end() ) ||
                       ( m_features.find( extension.second.promotedTo ) != m_features.end() ),
                     extension.second.xmlLine,
                     "extension promoted to unknown extension/version <" + extension.second.promotedTo + ">" );
    }

    // check for existence of any requirement
    for ( auto const & require : extension.second.requireData )
    {
      if ( !require.titles.empty() )
      {
        for ( auto const & title : require.titles )
        {
          checkForError( ( m_features.find( title ) != m_features.end() ) || ( m_extensions.find( title ) != m_extensions.end() ),
                         require.xmlLine,
                         "extension <" + extension.first + "> lists an unknown require <" + title + ">" );
        }
      }
    }
  }
}

void VulkanHppGenerator::checkFuncPointerCorrectness() const
{
  for ( auto const & funcPointer : m_funcPointers )
  {
    if ( !funcPointer.second.requirements.empty() )
    {
      checkForError( m_types.find( funcPointer.second.requirements ) != m_types.end(),
                     funcPointer.second.xmlLine,
                     "funcpointer requires unknown <" + funcPointer.second.requirements + ">" );
    }
    for ( auto const & argument : funcPointer.second.arguments )
    {
      checkForError( m_types.find( argument.type ) != m_types.end(), argument.xmlLine, "funcpointer argument of unknown type <" + argument.type + ">" );
    }
  }
}

void VulkanHppGenerator::checkHandleCorrectness() const
{
  // prepare handle checks by getting the VkObjectType enum
  auto objectTypeIt = m_enums.find( "VkObjectType" );
  assert( objectTypeIt != m_enums.end() );

  // handle checks
  for ( auto const & handle : m_handles )
  {
    // check the existence of the parent
    checkForError( m_handles.find( handle.second.parent ) != m_handles.end(),
                   handle.second.xmlLine,
                   "handle <" + handle.first + "> with unknown parent <" + handle.second.parent + ">" );

    // check existence of objTypeEnum used with this handle type
    if ( !handle.first.empty() )
    {
      assert( !handle.second.objTypeEnum.empty() );
      checkForError( std::find_if( objectTypeIt->second.values.begin(),
                                   objectTypeIt->second.values.end(),
                                   [&handle]( EnumValueData const & evd )
                                   { return evd.name == handle.second.objTypeEnum; } ) != objectTypeIt->second.values.end(),
                     handle.second.xmlLine,
                     "handle <" + handle.first + "> specifies unknown \"objtypeenum\" <" + handle.second.objTypeEnum + ">" );
    }
  }

  // check that all specified objectType values are used with a handle type
  for ( auto const & objectTypeValue : objectTypeIt->second.values )
  {
    if ( objectTypeValue.name != "VK_OBJECT_TYPE_UNKNOWN" )
    {
      checkForError( std::find_if( m_handles.begin(),
                                   m_handles.end(),
                                   [&objectTypeValue]( std::pair<std::string, HandleData> const & hd )
                                   { return hd.second.objTypeEnum == objectTypeValue.name; } ) != m_handles.end(),
                     objectTypeValue.xmlLine,
                     "VkObjectType value <" + objectTypeValue.name + "> not specified as \"objtypeenum\" for any handle" );
    }
  }
}

void VulkanHppGenerator::checkStructCorrectness() const
{
  for ( auto const & structAlias : m_structureAliases )
  {
    auto structIt = m_structures.find( structAlias.second.alias );
    checkForError( structIt != m_structures.end(), structAlias.second.xmlLine, "unknown struct alias <" + structAlias.second.alias + ">" );
  }

  for ( auto const & structAliasInverse : m_structureAliasesInverse )
  {
    auto structIt = m_structures.find( structAliasInverse.first );
    if ( structIt == m_structures.end() )
    {
      assert( !structAliasInverse.second.empty() );
      auto aliasIt = m_structureAliases.find( *structAliasInverse.second.begin() );
      assert( aliasIt != m_structureAliases.end() );
      checkForError( false, aliasIt->second.xmlLine, "struct <" + aliasIt->first + "> uses unknown alias <" + aliasIt->second.alias + ">" );
    }
  }

  std::set<std::string> sTypeValues;
  for ( auto const & structure : m_structures )
  {
    // check that a struct is referenced somewhere
    // I think, it's not forbidden to not reference a struct, but it would probably be not intended?
    auto typeIt = m_types.find( structure.first );
    assert( typeIt != m_types.end() );
    checkForError(
      !typeIt->second.referencedIn.empty(), structure.second.xmlLine, "structure <" + structure.first + "> not listed in any feature or extension" );

    // check for existence of all structs that are extended by this struct
    for ( auto const & extend : structure.second.structExtends )
    {
      checkForError( ( m_structures.find( extend ) != m_structures.end() ) || ( m_structureAliases.find( extend ) != m_structureAliases.end() ),
                     structure.second.xmlLine,
                     "struct <" + structure.first + "> extends unknown <" + extend + ">" );
    }

    // checks on the members of a struct
    checkStructMemberCorrectness( structure.first, structure.second.members, sTypeValues );
  }

  // enum VkStructureType checks (need to be after structure checks because of sTypeValues gathered there)
  auto structureTypeIt = m_enums.find( "VkStructureType" );
  assert( structureTypeIt != m_enums.end() );
  for ( auto const & enumValue : structureTypeIt->second.values )
  {
    if ( ( enumValue.name == "VK_STRUCTURE_TYPE_LOADER_INSTANCE_CREATE_INFO" ) || ( enumValue.name == "VK_STRUCTURE_TYPE_LOADER_DEVICE_CREATE_INFO" ) )
    {
      checkForError(
        sTypeValues.find( enumValue.name ) == sTypeValues.end(), enumValue.xmlLine, "Reserved VkStructureType enum value <" + enumValue.name + "> is used" );
    }
    else
    {
      checkForError( sTypeValues.erase( enumValue.name ) == 1, enumValue.xmlLine, "VkStructureType enum value <" + enumValue.name + "> never used" );
    }
  }
  assert( sTypeValues.empty() );
}

void VulkanHppGenerator::checkStructMemberCorrectness( std::string const &             structureName,
                                                       std::vector<MemberData> const & members,
                                                       std::set<std::string> &         sTypeValues ) const
{
  for ( auto const & member : members )
  {
    // check that all member types are required in some feature or extension
    checkForError(
      !member.type.type.starts_with( "Vk" ) ||
        ( std::find_if( m_features.begin(),
                        m_features.end(),
                        [&member]( std::pair<std::string, FeatureData> const & fd )
                        {
                          return std::find_if( fd.second.requireData.begin(),
                                               fd.second.requireData.end(),
                                               [&member]( RequireData const & rd ) {
                                                 return std::find_if( rd.types.begin(),
                                                                      rd.types.end(),
                                                                      [&member]( std::string const & t ) { return t == member.type.type; } ) != rd.types.end();
                                               } ) != fd.second.requireData.end();
                        } ) != m_features.end() ) ||
        ( std::find_if( m_extensions.begin(),
                        m_extensions.end(),
                        [&member]( std::pair<std::string, ExtensionData> const & ed )
                        {
                          return std::find_if( ed.second.requireData.begin(),
                                               ed.second.requireData.end(),
                                               [&member]( RequireData const & rd ) {
                                                 return std::find_if( rd.types.begin(),
                                                                      rd.types.end(),
                                                                      [&member]( std::string const & t ) { return t == member.type.type; } ) != rd.types.end();
                                               } ) != ed.second.requireData.end();
                        } ) != m_extensions.end() ),
      member.xmlLine,
      "struct member type <" + member.type.type + "> used in struct <" + structureName + "> is never listed for any feature or extension" );

    // if a member specifies a selector, that member is a union and the selector is an enum
    // check that there's a 1-1 connection between the specified selections and the values of that enum
    if ( !member.selector.empty() )
    {
      auto selectorIt = findStructMemberIt( member.selector, members );
      assert( selectorIt != members.end() );
      auto selectorEnumIt = m_enums.find( selectorIt->type.type );
      assert( selectorEnumIt != m_enums.end() );
      auto unionIt = m_structures.find( member.type.type );
      assert( ( unionIt != m_structures.end() ) && unionIt->second.isUnion );
      for ( auto const & unionMember : unionIt->second.members )
      {
        // check that each union member has a selection, that is a value of the seleting enum
        assert( !unionMember.selection.empty() );
        std::string const & selection = unionMember.selection;
        checkForError( std::find_if( selectorEnumIt->second.values.begin(),
                                     selectorEnumIt->second.values.end(),
                                     [&selection]( EnumValueData const & evd ) { return evd.name == selection; } ) != selectorEnumIt->second.values.end(),
                       unionMember.xmlLine,
                       "union member <" + unionMember.name + "> uses selection <" + selection + "> that is not part of the selector type <" +
                         selectorIt->type.type + ">" );
      }
    }

    // check that each member type is known
    checkForError( m_types.find( member.type.type ) != m_types.end(), member.xmlLine, "struct member uses unknown type <" + member.type.type + ">" );

    // check that any used constant is a known constant
    if ( !member.usedConstant.empty() )
    {
      checkForError( m_constants.find( member.usedConstant ) != m_constants.end(),
                     member.xmlLine,
                     "struct member array size uses unknown constant <" + member.usedConstant + ">" );
    }

    // checks if a value is specified
    if ( !member.value.empty() )
    {
      auto enumIt = m_enums.find( member.type.type );
      if ( enumIt != m_enums.end() )
      {
        // check that the value exists in the specified enum
        checkForError( std::find_if( enumIt->second.values.begin(),
                                     enumIt->second.values.end(),
                                     [&member]( auto const & evd ) { return member.value == evd.name; } ) != enumIt->second.values.end(),
                       member.xmlLine,
                       "value <" + member.value + "> for member <" + member.name + "> in structure <" + structureName + "> of enum type <" + member.type.type +
                         "> not listed" );
        // special handling for sType: no value should appear more than once
        if ( member.name == "sType" )
        {
          checkForError( sTypeValues.insert( member.value ).second, member.xmlLine, "sType value <" + member.value + "> has been used before" );
        }
      }
      else if ( member.type.type == "uint32_t" )
      {
        // check that a value for a uint32_t is all digits
        checkForError( member.value.find_first_not_of( "0123456789" ) == std::string::npos,
                       member.xmlLine,
                       "value <" + member.value + "> for member <" + member.name + "> in structure <" + structureName + "> of type <" + member.type.type +
                         "> is not a number" );
      }
      else
      {
        // don't know the type of the value -> error out
        checkForError( false,
                       member.xmlLine,
                       "member <" + member.name + "> in structure <" + structureName + "> holds value <" + member.value + "> for an unhandled type <" +
                         member.type.type + ">" );
      }
    }
  }
}

void VulkanHppGenerator::checkValidStructs( int line, std::map<std::string, std::string> const & attributes ) const
{
  auto it = attributes.find( "validstructs" );
  if ( it != attributes.end() )
  {
    std::vector<std::string> validStructs = tokenize( it->second, "," );
    for ( auto const & vs : validStructs )
    {
      checkForError( m_structures.find( vs ) != m_structures.end(), line, "unknown struct <" + vs + "> listed in attribute <validstructs>" );
    }
  }
}

std::string VulkanHppGenerator::combineDataTypes( std::map<size_t, VectorParamData> const & vectorParams,
                                                  std::vector<size_t> const &               returnParams,
                                                  bool                                      singular,
                                                  bool                                      enumerating,
                                                  std::vector<std::string> const &          dataTypes,
                                                  bool                                      unique,
                                                  bool                                      raii ) const
{
  assert( dataTypes.size() == returnParams.size() );

  std::vector<std::string> modifiedDataTypes( dataTypes.size() );
  for ( size_t i = 0; i < returnParams.size(); ++i )
  {
    auto vectorParamIt   = vectorParams.find( returnParams[i] );
    modifiedDataTypes[i] = ( vectorParamIt == vectorParams.end() || singular )
                           ? dataTypes[i]
                           : ( "std::vector<" + dataTypes[i] +
                               ( raii || unique ? ">" : ( ", " + startUpperCase( stripPrefix( dataTypes[i], "VULKAN_HPP_NAMESPACE::" ) ) + "Allocator>" ) ) );
  }

  std::string combinedType;
  switch ( modifiedDataTypes.size() )
  {
    case 0: combinedType = "void"; break;
    case 1: combinedType = modifiedDataTypes[0]; break;
    case 2:
      assert( !enumerating || ( ( vectorParams.find( returnParams[1] ) != vectorParams.end() ) &&
                                ( vectorParams.find( returnParams[1] )->second.lenParam == returnParams[0] ) ) );
      combinedType = enumerating ? modifiedDataTypes[1] : ( "std::pair<" + modifiedDataTypes[0] + ", " + modifiedDataTypes[1] + ">" );
      break;
    case 3:
      assert( enumerating && ( vectorParams.size() == 2 ) && ( vectorParams.begin()->first == returnParams[1] ) &&
              ( vectorParams.begin()->second.lenParam == returnParams[0] ) && ( std::next( vectorParams.begin() )->first == returnParams[2] ) &&
              ( std::next( vectorParams.begin() )->second.lenParam == returnParams[0] ) );
      combinedType = "std::pair<" + modifiedDataTypes[1] + ", " + modifiedDataTypes[2] + ">";
      break;
    default: assert( false ); break;
  }
  return combinedType;
}

bool VulkanHppGenerator::containsArray( std::string const & type ) const
{
  // a simple recursive check if a type is or contains an array
  auto structureIt = m_structures.find( type );
  bool found       = false;
  if ( structureIt != m_structures.end() )
  {
    for ( auto memberIt = structureIt->second.members.begin(); memberIt != structureIt->second.members.end() && !found; ++memberIt )
    {
      found = !memberIt->arraySizes.empty() || containsArray( memberIt->type.type );
    }
  }
  return found;
}

bool VulkanHppGenerator::containsFuncPointer( std::string const & type ) const
{
  // a simple recursive check if a type contains a funcpointer
  auto structureIt = m_structures.find( type );
  bool found       = false;
  if ( structureIt != m_structures.end() )
  {
    for ( auto memberIt = structureIt->second.members.begin(); memberIt != structureIt->second.members.end() && !found; ++memberIt )
    {
      found = ( m_funcPointers.find( memberIt->type.type ) != m_funcPointers.end() ) ||
              ( ( memberIt->type.type != type ) && containsFuncPointer( memberIt->type.type ) );
    }
  }
  return found;
}

bool VulkanHppGenerator::containsFloatingPoints( std::vector<MemberData> const & members ) const
{
  for ( auto const & m : members )
  {
    if ( ( ( m.type.type == "float" ) || ( m.type.type == "double" ) ) && m.type.isValue() )
    {
      return true;
    }
  }
  return false;
}

bool VulkanHppGenerator::containsUnion( std::string const & type ) const
{
  // a simple recursive check if a type is or contains a union
  auto structureIt = m_structures.find( type );
  bool found       = false;
  if ( structureIt != m_structures.end() )
  {
    found = structureIt->second.isUnion;
    for ( auto memberIt = structureIt->second.members.begin(); memberIt != structureIt->second.members.end() && !found; ++memberIt )
    {
      found = memberIt->type.isValue() && containsUnion( memberIt->type.type );
    }
  }
  return found;
}

std::vector<size_t> VulkanHppGenerator::determineConstPointerParams( std::vector<ParamData> const & params ) const
{
  std::vector<size_t> constPointerParams;

  for ( size_t i = 0; i < params.size(); i++ )
  {
    // very special handling for some types, which come in as non-const pointers, but are meant as const-pointers
    if ( params[i].type.isConstPointer() ||
         ( params[i].type.isNonConstPointer() && ( specialPointerTypes.find( params[i].type.type ) != specialPointerTypes.end() ) ) )
    {
      constPointerParams.push_back( i );
    }
  }
  return constPointerParams;
}

std::vector<std::string> VulkanHppGenerator::determineDataTypes( std::vector<VulkanHppGenerator::ParamData> const & params,
                                                                 std::map<size_t, VectorParamData> const &          vectorParams,
                                                                 std::vector<size_t> const &                        returnParams,
                                                                 std::set<size_t> const &                           templatedParams ) const
{
  std::vector<std::string> dataTypes;
  for ( auto rp : returnParams )
  {
    if ( templatedParams.find( rp ) != templatedParams.end() )
    {
      auto vectorParamIt = vectorParams.find( rp );
      if ( ( vectorParamIt != vectorParams.end() ) && ( std::find( returnParams.begin(), returnParams.end(), vectorParamIt->first ) != returnParams.end() ) &&
           ( std::find( returnParams.begin(), returnParams.end(), vectorParamIt->second.lenParam ) != returnParams.end() ) )
      {
        dataTypes.push_back( "uint8_t" );
      }
      else
      {
        dataTypes.push_back( ( stripPrefix( params[rp].name, "p" ) + "Type" ) );
      }
    }
    else
    {
      dataTypes.push_back( trimEnd( stripPostfix( params[rp].type.compose( "VULKAN_HPP_NAMESPACE" ), "*" ) ) );
    }
  }
  return dataTypes;
}

size_t VulkanHppGenerator::determineDefaultStartIndex( std::vector<ParamData> const & params, std::set<size_t> const & skippedParams ) const
{
  // determine the index where the arguments start to have defaults
  size_t defaultStartIndex = INVALID_INDEX;
  for ( int i = static_cast<int>( params.size() ) - 1; ( 0 <= i ) && ( params[i].optional || ( skippedParams.find( i ) != skippedParams.end() ) ); --i )
  {
    defaultStartIndex = i;
  }
  return defaultStartIndex;
}

bool VulkanHppGenerator::determineEnumeration( std::map<size_t, VectorParamData> const & vectorParams, std::vector<size_t> const & returnParams ) const
{
  // a command is considered to be enumerating some data, if for at least one vectorParam both, the data and the counter, are returnParams
  return std::find_if( vectorParams.begin(),
                       vectorParams.end(),
                       [&returnParams]( auto const & vp )
                       {
                         return std::find( returnParams.begin(), returnParams.end(), vp.first ) != returnParams.end() &&
                                std::find( returnParams.begin(), returnParams.end(), vp.second.lenParam ) != returnParams.end();
                       } ) != vectorParams.end();
}

size_t VulkanHppGenerator::determineInitialSkipCount( std::string const & command ) const
{
  // determine the number of arguments to skip for a function
  // -> 0: the command is not bound to an instance or a device (the corresponding handle has no name)
  // -> 1: the command bound to an instance or a device (the corresponding handle has a name)
  // -> 2: the command has been moved to a second handle
  auto commandIt = m_commands.find( command );
  assert( commandIt != m_commands.end() );
  auto handleIt = m_handles.find( commandIt->second.handle );
  assert( handleIt != m_handles.end() );
  if ( handleIt->second.commands.find( command ) == handleIt->second.commands.end() )
  {
    assert( 1 < commandIt->second.params.size() );
    assert( m_handles.find( commandIt->second.params[1].type.type ) != m_handles.end() );
    return 2;
  }
  else
  {
    return handleIt->first.empty() ? 0 : 1;
  }
}

std::vector<size_t> VulkanHppGenerator::determineReturnParams( std::vector<ParamData> const & params ) const
{
  std::vector<size_t> nonConstPointerParamIndices;

  for ( size_t i = 0; i < params.size(); i++ )
  {
    // very special handling of parameters of some types, which always come as a non-const pointer but are not meant
    // to be a potential return value!
    if ( params[i].type.isNonConstPointer() && ( specialPointerTypes.find( params[i].type.type ) == specialPointerTypes.end() ) )
    {
      nonConstPointerParamIndices.push_back( i );
    }
  }
  return nonConstPointerParamIndices;
}

std::vector<std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator>
  VulkanHppGenerator::determineRAIIHandleConstructors( std::string const & handleType, std::map<std::string, CommandData>::const_iterator destructorIt ) const
{
  std::vector<std::map<std::string, CommandData>::const_iterator> constructorIts;
  auto                                                            isConstructorCandidate = [&handleType]( std::pair<std::string, CommandData> const & cd )
  {
    return std::find_if( cd.second.params.begin(),
                         cd.second.params.end(),
                         [&handleType]( ParamData const & pd )
                         { return ( pd.type.type == handleType ) && pd.type.isNonConstPointer(); } ) != cd.second.params.end();
  };
  for ( auto commandIt = m_commands.begin(); commandIt != m_commands.end(); )
  {
    // find the commands that get a non-const pointer to the handleType, that is, return a handle type
    commandIt = std::find_if( commandIt, m_commands.end(), isConstructorCandidate );
    if ( commandIt != m_commands.end() )
    {
      // only commands that provide all information needed for the destructor can be considered a constructor!
      bool valid = true;
      if ( destructorIt != m_commands.end() )
      {
        // get the destructors parameter to the handleType
        auto desctructorHandleParamIt = std::find_if( destructorIt->second.params.begin(),
                                                      destructorIt->second.params.end(),
                                                      [&handleType]( ParamData const & pd ) { return pd.type.type == handleType; } );
        assert( desctructorHandleParamIt != destructorIt->second.params.end() );

        // lambda to check if a destructor parameter is a parameter of the constructor candidate
        // (or it's just the len parameter, which is not needed for the constructor)
        auto isConstructorCandidateParam = [&desctructorHandleParamIt, &commandIt, this]( ParamData const & destructorParam )
        {
          // check if the destructor param type equals this param type, or, if this param type is a struct, is part of
          // that struct
          auto isDestructorParamType = [&destructorParam, this]( ParamData const & pd )
          {
            if ( pd.type.type != destructorParam.type.type )
            {
              // check if the destructor param type equals a structure member type
              auto structureIt = m_structures.find( pd.type.type );
              return ( structureIt != m_structures.end() ) &&
                     ( findStructMemberItByType( destructorParam.type.type, structureIt->second.members ) != structureIt->second.members.end() );
            }
            return true;
          };

          return ( destructorParam.name == desctructorHandleParamIt->len ) ||
                 ( std::find_if( commandIt->second.params.begin(), commandIt->second.params.end(), isDestructorParamType ) != commandIt->second.params.end() );
        };

        // the constructor candidate is valid, if none of the (relevant) destructor parameters is missing in the
        // constructor candidate params
        valid = ( std::find_if_not( destructorIt->second.params.begin(), destructorIt->second.params.end(), isConstructorCandidateParam ) ==
                  destructorIt->second.params.end() );
      }
      if ( valid )
      {
        // filter out alias functions
        if ( commandIt->second.alias.empty() )
        {
          constructorIts.push_back( commandIt );
        }
      }
      ++commandIt;
    }
  }
  assert( !constructorIts.empty() );
  return constructorIts;
}

std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator VulkanHppGenerator::determineRAIIHandleDestructor( std::string const & handleType ) const
{
  std::string type         = stripPrefix( handleType, "Vk" );
  auto        destructorIt = m_commands.find( "vkDestroy" + type );
  if ( destructorIt == m_commands.end() )
  {
    destructorIt = m_commands.find( "vkFree" + type + "s" );
    if ( destructorIt == m_commands.end() )
    {
      destructorIt = m_commands.find( "vkRelease" + type );
      if ( destructorIt == m_commands.end() )
      {
        if ( handleType == "VkDeviceMemory" )
        {
          // special handling for vkDeviceMemory
          destructorIt = m_commands.find( "vkFreeMemory" );
          assert( destructorIt != m_commands.end() );
        }
        else if ( handleType == "VkDisplayKHR" )
        {
          // special handling for VkDisplayKHR
          destructorIt = m_commands.find( "vkReleaseDisplayEXT" );
          assert( destructorIt != m_commands.end() );
        }
        else
        {
          assert( ( handleType == "VkDisplayModeKHR" ) || ( handleType == "VkPhysicalDevice" ) || ( handleType == "VkQueue" ) );
        }
      }
    }
  }
  return destructorIt;
}

std::set<size_t> VulkanHppGenerator::determineSingularParams( size_t returnParam, std::map<size_t, VectorParamData> const & vectorParams ) const
{
  auto returnVectorIt = vectorParams.find( returnParam );
  assert( returnVectorIt != vectorParams.end() );
  std::set<size_t> singularParams;
  singularParams.insert( returnVectorIt->second.lenParam );
  for ( auto const & vpi : vectorParams )
  {
    if ( vpi.second.lenParam == returnVectorIt->second.lenParam )
    {
      singularParams.insert( vpi.first );
    }
  }
  return singularParams;
}

std::set<size_t> VulkanHppGenerator::determineSkippedParams( std::vector<ParamData> const &            params,
                                                             size_t                                    initialSkipCount,
                                                             std::map<size_t, VectorParamData> const & vectorParams,
                                                             std::vector<size_t> const &               returnParams,
                                                             bool                                      singular ) const
{
  // skip the initial skips (get fed by the object)
  assert( initialSkipCount <= params.size() );
  std::set<size_t> skippedParams;
  for ( size_t i = 0; i < initialSkipCount; ++i )
  {
    skippedParams.insert( i );
  }

  // skip the size parameters (get derived from an array), and a stride parameter
  for ( auto const & vpi : vectorParams )
  {
    assert( !params[vpi.first].len.empty() );
    if ( ( ( std::find_if( returnParams.begin(), returnParams.end(), [&vpi]( size_t rpi ) { return vpi.first == rpi; } ) == returnParams.end() ) &&
           isParam( params[vpi.first].len, params ) ) ||
         ( singular && params[vpi.second.lenParam].type.isValue() ) )
    {
      skippedParams.insert( vpi.second.lenParam );
    }
    if ( vpi.second.strideParam != INVALID_INDEX )
    {
      skippedParams.insert( vpi.second.strideParam );
    }
  }

  // skip the return parameters (get resolved by local variables to be returned)
  skippedParams.insert( returnParams.begin(), returnParams.end() );

  return skippedParams;
}

std::string VulkanHppGenerator::determineSubStruct( std::pair<std::string, StructureData> const & structure ) const
{
  if ( structure.second.members.front().name != "sType" )
  {
    // check if sd is a substruct of structure
    auto isSubStruct = [&structure]( std::pair<std::string, StructureData> const & sd )
    {
      // member-by-member comparison of type and name
      auto memberIt = structure.second.members.begin();
      auto isMember = [&memberIt]( MemberData const & md )
      {
        if ( ( md.type == memberIt->type ) && ( md.name == memberIt->name ) )
        {
          ++memberIt;
          return true;
        }
        return false;
      };

      return ( sd.second.members.size() < structure.second.members.size() ) &&
             ( std::find_if_not( sd.second.members.begin(), sd.second.members.end(), isMember ) == sd.second.members.end() );
    };

    // look for a struct in m_structures that starts identically to structure
    auto structIt = std::find_if( m_structures.begin(), m_structures.end(), isSubStruct );
    return ( structIt == m_structures.end() ) ? "" : structIt->first;
  }
  return "";
}

std::map<size_t, VulkanHppGenerator::VectorParamData> VulkanHppGenerator::determineVectorParams( std::vector<ParamData> const & params ) const
{
  std::map<size_t, VectorParamData> vectorParams;

  // look for the parameters whose len equals the name of an other parameter
  for ( size_t i = 0; i < params.size(); i++ )
  {
    if ( !params[i].len.empty() && ( params[i].len != "null-terminated" ) )
    {
      VectorParamData & vpd = vectorParams[i];

      std::string len;
      if ( altLens.find( params[i].len ) != altLens.end() )
      {
        checkForError( params[i].len == "(samples + 31) / 32", params[i].xmlLine, "unknown command parameter len <" + params[i].len + ">" );
        len = "samples";
      }
      else
      {
        len = params[i].len;
      }
      auto lenIt =
        std::find_if( params.begin(), params.end(), [&len, this]( auto const & pd ) { return ( len == pd.name ) || isLenByStructMember( len, pd ); } );
      assert( lenIt != params.end() );
      vpd.lenParam = std::distance( params.begin(), lenIt );
      if ( !params[i].stride.empty() )
      {
        std::string const & stride   = params[i].stride;
        auto                strideIt = std::find_if( params.begin(), params.end(), [&stride]( auto const & pd ) { return stride == pd.name; } );
        assert( strideIt != params.end() );
        vpd.strideParam = std::distance( params.begin(), strideIt );
      }
    }
  }
  return vectorParams;
}

std::set<size_t> VulkanHppGenerator::determineVoidPointerParams( std::vector<ParamData> const & params ) const
{
  std::set<size_t> voidPointerParams;

  for ( size_t i = 0; i < params.size(); i++ )
  {
    if ( !params[i].type.isValue() && ( params[i].type.type == "void" ) && ( params[i].type.postfix != "**" ) )
    {
      voidPointerParams.insert( i );
    }
  }
  return voidPointerParams;
}

void VulkanHppGenerator::distributeSecondLevelCommands( std::set<std::string> const & specialFunctions )
{
  // distribute commands from instance/device to second-level handles, like Queue, Event,... for RAII handles
  for ( auto & handle : m_handles )
  {
    if ( !handle.first.empty() )
    {
      for ( auto command = handle.second.commands.begin(); command != handle.second.commands.end(); )
      {
        bool foundCommand = false;
        if ( specialFunctions.find( *command ) == specialFunctions.end() )
        {
          auto commandIt = m_commands.find( *command );
          assert( commandIt != m_commands.end() );
          assert( commandIt->second.params.front().type.type == handle.first );
          if ( ( 1 < commandIt->second.params.size() ) && ( isHandleType( commandIt->second.params[1].type.type ) ) && !commandIt->second.params[1].optional )
          {
            auto handleIt = m_handles.find( commandIt->second.params[1].type.type );
            assert( handleIt != m_handles.end() );
            assert( !handleIt->second.constructorIts.empty() );
            if ( ( *handleIt->second.constructorIts.begin() )->second.handle == handle.first )
            {
              assert( std::find_if( handleIt->second.constructorIts.begin(),
                                    handleIt->second.constructorIts.end(),
                                    [&handle]( auto const & constructorIt )
                                    { return constructorIt->second.handle != handle.first; } ) == handleIt->second.constructorIts.end() );
              handleIt->second.secondLevelCommands.insert( *command );
              command      = handle.second.commands.erase( command );
              foundCommand = true;
            }
          }
        }
        if ( !foundCommand )
        {
          ++command;
        }
      }
    }
  }
}

std::string VulkanHppGenerator::findBaseName( std::string aliasName, std::map<std::string, EnumAliasData> const & aliases ) const
{
  std::string baseName = aliasName;
  auto        aliasIt  = aliases.find( baseName );
  while ( aliasIt != aliases.end() )
  {
    baseName = aliasIt->second.name;
    aliasIt  = aliases.find( baseName );
  }
  return baseName;
}

std::vector<VulkanHppGenerator::MemberData>::const_iterator VulkanHppGenerator::findStructMemberIt( std::string const &             name,
                                                                                                    std::vector<MemberData> const & memberData ) const
{
  return std::find_if( memberData.begin(), memberData.end(), [&name]( MemberData const & md ) { return md.name == name; } );
}

std::vector<VulkanHppGenerator::MemberData>::const_iterator VulkanHppGenerator::findStructMemberItByType( std::string const &             type,
                                                                                                          std::vector<MemberData> const & memberData ) const
{
  return std::find_if( memberData.begin(), memberData.end(), [&type]( MemberData const & md ) { return md.type.type == type; } );
}

std::pair<std::string, std::string> VulkanHppGenerator::generateAllocatorTemplates( std::vector<size_t> const &               returnParams,
                                                                                    std::vector<std::string> const &          returnDataTypes,
                                                                                    std::map<size_t, VectorParamData> const & vectorParams,
                                                                                    bool                                      definition,
                                                                                    bool                                      singular,
                                                                                    bool                                      unique,
                                                                                    bool                                      chained ) const
{
  assert( returnParams.size() == returnDataTypes.size() );
  std::string allocatorTemplates;
  if ( !singular )
  {
    for ( size_t i = 0; i < returnParams.size(); i++ )
    {
      if ( vectorParams.find( returnParams[i] ) != vectorParams.end() )
      {
        if ( chained )
        {
          allocatorTemplates += "typename StructureChainAllocator";
          if ( !definition )
          {
            allocatorTemplates += " = std::allocator<StructureChain>";
          }
        }
        else
        {
          allocatorTemplates += "typename " + startUpperCase( stripPrefix( returnDataTypes[i], "VULKAN_HPP_NAMESPACE::" ) ) + "Allocator";
          if ( !definition )
          {
            allocatorTemplates += " = std::allocator<" + ( unique ? ( "UniqueHandle<" + returnDataTypes[i] + ", Dispatch>" ) : returnDataTypes[i] ) + ">";
          }
        }
        allocatorTemplates += ", ";
      }
    }
  }
  std::string uniqueHandleAllocatorTemplates;
  if ( unique && !allocatorTemplates.empty() )
  {
    uniqueHandleAllocatorTemplates = ", " + stripPostfix( allocatorTemplates, ", " );
    allocatorTemplates.clear();
  }
  return std::make_pair( allocatorTemplates, uniqueHandleAllocatorTemplates );
}

std::string VulkanHppGenerator::generateArgumentListEnhanced( std::vector<ParamData> const &            params,
                                                              std::vector<size_t> const &               returnParams,
                                                              std::map<size_t, VectorParamData> const & vectorParams,
                                                              std::set<size_t> const &                  skippedParams,
                                                              std::set<size_t> const &                  singularParams,
                                                              std::set<size_t> const &                  templatedParams,
                                                              bool                                      definition,
                                                              bool                                      withAllocators,
                                                              bool                                      structureChain,
                                                              bool                                      withDispatcher ) const
{
  size_t defaultStartIndex = withAllocators ? ~0 : determineDefaultStartIndex( params, skippedParams );

  std::string argumentList;
  bool        encounteredArgument = false;
  for ( size_t i = 0; i < params.size(); ++i )
  {
    if ( skippedParams.find( i ) == skippedParams.end() )
    {
      if ( encounteredArgument )
      {
        argumentList += ", ";
      }
      bool hasDefaultAssignment = false;

      std::string composedType = params[i].type.compose( "VULKAN_HPP_NAMESPACE" );

      if ( singularParams.find( i ) != singularParams.end() )
      {
        assert( !params[i].optional );
        assert( params[i].type.isConstPointer() && !params[i].len.empty() && !isLenByStructMember( params[i].len, params ) &&
                params[i].type.type.starts_with( "Vk" ) );
        assert( !isHandleType( params[i].type.type ) );
        assert( composedType.ends_with( " *" ) );
        argumentList += stripPostfix( composedType, " *" ) + " & " + stripPluralS( startLowerCase( stripPrefix( params[i].name, "p" ) ) );
      }
      else if ( params[i].type.isConstPointer() )
      {
        assert( composedType.ends_with( " *" ) );
        std::string name = startLowerCase( stripPrefix( params[i].name, "p" ) );
        if ( params[i].len.empty() )
        {
          assert( withDispatcher || !isHandleType( params[i].type.type ) );
          assert( !params[i].type.prefix.empty() && ( params[i].type.postfix == "*" ) );
          assert( params[i].arraySizes.empty() );
          if ( params[i].type.type == "void" )
          {
            assert( !params[i].optional );
            argumentList += ( templatedParams.find( i ) == templatedParams.end() ) ? ( composedType + " " + params[i].name )
                                                                                   : ( stripPrefix( params[i].name, "p" ) + "Type const & " + name );
          }
          else if ( params[i].optional )
          {
            argumentList += "Optional<" + stripPostfix( composedType, " *" ) + "> " + name +
                            ( ( definition || withAllocators ) ? "" : " VULKAN_HPP_DEFAULT_ARGUMENT_NULLPTR_ASSIGNMENT" );
            hasDefaultAssignment = true;
          }
          else
          {
            argumentList += stripPostfix( composedType, " *" ) + " & " + name;
          }
        }
        else
        {
          // a const-pointer with a non-empty len is either null-terminated (aka a string) or represented by an
          // ArrayProxy
          assert( params[i].arraySizes.empty() );
          if ( params[i].len == "null-terminated" )
          {
            assert( params[i].type.type == "char" );
            if ( params[i].optional )
            {
              argumentList +=
                "Optional<const std::string> " + name + ( ( definition || withAllocators ) ? "" : " VULKAN_HPP_DEFAULT_ARGUMENT_NULLPTR_ASSIGNMENT" );
              hasDefaultAssignment = true;
            }
            else
            {
              argumentList += "const std::string & " + name;
            }
          }
          else
          {
            // an ArrayProxy also covers no data, so any optional flag can be ignored here
            std::string type = stripPostfix( composedType, " *" );
            size_t      pos  = type.find( "void" );
            if ( pos != std::string::npos )
            {
              type.replace( pos, 4, stripPrefix( params[i].name, "p" ) + "Type" );
            }
            argumentList +=
              std::string( "VULKAN_HPP_NAMESPACE::" ) + ( params[i].stride.empty() ? "" : "Strided" ) + "ArrayProxy<" + type + "> const & " + name;
            if ( params[i].optional && !definition )
            {
              assert( params[i].stride.empty() );
              argumentList += " VULKAN_HPP_DEFAULT_ARGUMENT_NULLPTR_ASSIGNMENT";
              hasDefaultAssignment = true;
            }
          }
        }
      }
      else if ( params[i].type.isNonConstPointer() )
      {
        assert( withDispatcher || !isHandleType( params[i].type.type ) );
        assert( params[i].len.empty() && !params[i].optional );
        assert( composedType.ends_with( " *" ) );
        argumentList += stripPostfix( composedType, " *" ) + " & " + params[i].name;
      }
      else
      {
        assert( params[i].type.isValue() );
        argumentList += composedType + " " + params[i].name + generateCArraySizes( params[i].arraySizes );
      }
      argumentList += std::string( !definition && ( defaultStartIndex <= i ) && !hasDefaultAssignment ? " VULKAN_HPP_DEFAULT_ARGUMENT_ASSIGNMENT" : "" );
      encounteredArgument = true;
    }
  }
  if ( withAllocators )
  {
    if ( structureChain )
    {
      if ( encounteredArgument )
      {
        argumentList += ", ";
      }
      argumentList += "StructureChainAllocator & structureChainAllocator";
      encounteredArgument = true;
    }
    else
    {
      for ( auto sp : skippedParams )
      {
        if ( !params[sp].len.empty() )
        {
          if ( encounteredArgument )
          {
            argumentList += ", ";
          }
          std::string type;
          if ( templatedParams.find( sp ) != templatedParams.end() )
          {
            auto vectorParamIt = vectorParams.find( sp );
            if ( ( vectorParamIt != vectorParams.end() ) &&
                 ( std::find( returnParams.begin(), returnParams.end(), vectorParamIt->first ) != returnParams.end() ) &&
                 ( std::find( returnParams.begin(), returnParams.end(), vectorParamIt->second.lenParam ) != returnParams.end() ) )
            {
              type = "Uint8_t";
            }
            else
            {
              type = stripPrefix( params[sp].name, "p" ) + "Type";
            }
          }
          else
          {
            type = ( params[sp].type.type == "void" ) ? "Uint8_t" : startUpperCase( stripPrefix( params[sp].type.type, "Vk" ) );
          }
          argumentList += type + "Allocator & " + startLowerCase( type ) + "Allocator";
          encounteredArgument = true;
        }
      }
    }
  }
  if ( withDispatcher )
  {
    if ( encounteredArgument )
    {
      argumentList += ", ";
    }
    argumentList += std::string( "Dispatch const & d" ) + ( definition ? "" : " VULKAN_HPP_DEFAULT_DISPATCHER_ASSIGNMENT" );
  }
  return argumentList;
}

std::string VulkanHppGenerator::generateArgumentListStandard( std::vector<ParamData> const & params, std::set<size_t> const & skippedParams ) const
{
  std::string argumentList;
  for ( size_t i = 0; i < params.size(); ++i )
  {
    if ( skippedParams.find( i ) == skippedParams.end() )
    {
      argumentList += params[i].type.compose( "VULKAN_HPP_NAMESPACE" ) + " " + params[i].name + generateCArraySizes( params[i].arraySizes ) + ", ";
    }
  }
  argumentList += "Dispatch const & d ";
  return argumentList;
}

std::string VulkanHppGenerator::generateArgumentTemplates( std::vector<ParamData> const &            params,
                                                           std::vector<size_t> const &               returnParams,
                                                           std::map<size_t, VectorParamData> const & vectorParams,
                                                           std::set<size_t> const &                  templatedParams,
                                                           bool                                      chained,
                                                           bool                                      raii ) const
{
  std::string argumentTemplates;
  if ( !templatedParams.empty() )
  {
    assert( !chained );
    for ( auto t : templatedParams )
    {
      assert( params[t].name.starts_with( "p" ) );
      auto vectorParamIt = vectorParams.find( t );
      if ( ( vectorParamIt == vectorParams.end() ) || ( std::find( returnParams.begin(), returnParams.end(), vectorParamIt->first ) == returnParams.end() ) ||
           ( std::find( returnParams.begin(), returnParams.end(), vectorParamIt->second.lenParam ) == returnParams.end() ) )
      {
        // only templated parameters that are not part of an enumeration are really templated
        argumentTemplates += "typename " + stripPrefix( params[t].name, "p" ) + "Type, ";
      }
    }
  }
  else if ( chained )
  {
    argumentTemplates = ( returnParams.size() == 1 ) ? "typename X, typename Y, typename... Z, " : "typename StructureChain, ";
  }
  if ( !argumentTemplates.empty() && raii )
  {
    argumentTemplates = "template <" + stripPostfix( argumentTemplates, ", " ) + ">";
  }
  return argumentTemplates;
}

std::string VulkanHppGenerator::generateBaseTypes() const
{
  assert( !m_baseTypes.empty() );
  const std::string basetypesTemplate = R"(
  //==================
  //=== BASE TYPEs ===
  //==================

${basetypes}
)";

  std::string basetypes;
  for ( auto const & baseType : m_baseTypes )
  {
    // filter out VkFlags and VkFlags64, as they are mapped to our own Flags class
    if ( ( baseType.first != "VkFlags" ) && ( baseType.first != "VkFlags64" ) )
    {
      basetypes += "  using " + stripPrefix( baseType.first, "Vk" ) + " = " + baseType.second.typeInfo.compose( "VULKAN_HPP_NAMESPACE" ) + ";\n";
    }
  }

  return replaceWithMap( basetypesTemplate, { { "basetypes", basetypes } } );
}

std::string VulkanHppGenerator::generateBitmask( std::map<std::string, BitmaskData>::const_iterator bitmaskIt ) const
{
  auto bitmaskBitsIt = m_enums.find( bitmaskIt->second.requirements );
  assert( bitmaskBitsIt != m_enums.end() );

  std::string bitmaskName = stripPrefix( bitmaskIt->first, "Vk" );
  std::string enumName    = stripPrefix( bitmaskBitsIt->first, "Vk" );

  // each Flags class is using the class 'Flags' with the corresponding FlagBits enum as the template parameter
  std::string str = "\n  using " + bitmaskName + " = Flags<" + enumName + ">;\n";

  std::string alias = bitmaskIt->second.alias.empty() ? "" : ( "\n  using " + stripPrefix( bitmaskIt->second.alias, "Vk" ) + " = " + bitmaskName + ";\n" );

  if ( bitmaskBitsIt->second.values.empty() )
  {
    str += alias + "\n";
  }
  else
  {
    static const std::string bitmaskTemplate = R"(
  template <> struct FlagTraits<${enumName}>
  {
    enum : ${bitmaskType}
    {
      allFlags = ${allFlags}
    };
  };

  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR ${bitmaskName} operator|( ${enumName} bit0, ${enumName} bit1 ) VULKAN_HPP_NOEXCEPT
  {
    return ${bitmaskName}( bit0 ) | bit1;
  }

  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR ${bitmaskName} operator&( ${enumName} bit0, ${enumName} bit1 ) VULKAN_HPP_NOEXCEPT
  {
    return ${bitmaskName}( bit0 ) & bit1;
  }

  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR ${bitmaskName} operator^( ${enumName} bit0, ${enumName} bit1 ) VULKAN_HPP_NOEXCEPT
  {
    return ${bitmaskName}( bit0 ) ^ bit1;
  }

  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR ${bitmaskName} operator~( ${enumName} bits ) VULKAN_HPP_NOEXCEPT
  {
    return ~( ${bitmaskName}( bits ) );
  }
${alias}
)";

    std::string allFlags;
    bool        encounteredFlag = false;
    std::string previousEnter, previousLeave;
    for ( auto const & value : bitmaskBitsIt->second.values )
    {
      auto [enter, leave]   = generateProtection( value.extension, value.protect );
      std::string valueName = generateEnumValueName( bitmaskBitsIt->first, value.name, true, m_tags );
      allFlags += ( ( previousEnter != enter ) ? ( "\n" + previousLeave + enter ) : "\n" ) + "        " + ( encounteredFlag ? "| " : "  " ) +
                  bitmaskIt->second.type + "( " + enumName + "::" + valueName + " )";
      encounteredFlag = true;
      previousEnter   = enter;
      previousLeave   = leave;
    }
    if ( !previousLeave.empty() )
    {
      assert( previousLeave.ends_with( "\n" ) );
      previousLeave.resize( previousLeave.size() - strlen( "\n" ) );
      allFlags += "\n" + previousLeave;
    }

    str += replaceWithMap(
      bitmaskTemplate,
      { { "alias", alias }, { "allFlags", allFlags }, { "bitmaskName", bitmaskName }, { "bitmaskType", bitmaskIt->second.type }, { "enumName", enumName } } );
  }

  return str;
}

std::string VulkanHppGenerator::generateBitmasks() const
{
  const std::string bitmasksTemplate = R"(
  //================
  //=== BITMASKs ===
  //================

${bitmasks}
)";

  std::string           bitmasks;
  std::set<std::string> listedBitmasks;
  for ( auto const & feature : m_features )
  {
    bitmasks += generateBitmasks( feature.second.requireData, listedBitmasks, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    bitmasks += generateBitmasks( extIt.second->second.requireData, listedBitmasks, extIt.second->first );
  }

  return replaceWithMap( bitmasksTemplate, { { "bitmasks", bitmasks } } );
}

std::string
  VulkanHppGenerator::generateBitmasks( std::vector<RequireData> const & requireData, std::set<std::string> & listedBitmasks, std::string const & title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto bitmaskIt = m_bitmasks.find( type );
      if ( ( bitmaskIt != m_bitmasks.end() ) && ( listedBitmasks.find( type ) == listedBitmasks.end() ) )
      {
        listedBitmasks.insert( type );
        str += generateBitmask( bitmaskIt );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateBitmasksToString() const
{
  const std::string bitmasksToStringTemplate = R"(
  //==========================
  //=== BITMASKs to_string ===
  //==========================

${bitmasksToString}
)";

  std::string           bitmasksToString;
  std::set<std::string> listedBitmasks;
  for ( auto const & feature : m_features )
  {
    bitmasksToString += generateBitmasksToString( feature.second.requireData, listedBitmasks, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    bitmasksToString += generateBitmasksToString( extIt.second->second.requireData, listedBitmasks, extIt.second->first );
  }

  return replaceWithMap( bitmasksToStringTemplate, { { "bitmasksToString", bitmasksToString } } );
}

std::string VulkanHppGenerator::generateBitmasksToString( std::vector<RequireData> const & requireData,
                                                          std::set<std::string> &          listedBitmasks,
                                                          std::string const &              title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto bitmaskIt = m_bitmasks.find( type );
      if ( ( bitmaskIt != m_bitmasks.end() ) && ( listedBitmasks.find( type ) == listedBitmasks.end() ) )
      {
        listedBitmasks.insert( type );
        str += generateBitmaskToString( bitmaskIt );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateBitmaskToString( std::map<std::string, BitmaskData>::const_iterator bitmaskIt ) const
{
  auto bitmaskBitsIt = m_enums.find( bitmaskIt->second.requirements );
  assert( bitmaskBitsIt != m_enums.end() );

  std::string bitmaskName = stripPrefix( bitmaskIt->first, "Vk" );
  std::string enumName    = stripPrefix( bitmaskBitsIt->first, "Vk" );

  std::string str;
  if ( bitmaskBitsIt->second.values.empty() )
  {
    static std::string bitmaskToStringTemplate = R"(
  VULKAN_HPP_INLINE std::string to_string( ${bitmaskName} )
  {
    return "{}";
  }
)";
    str += replaceWithMap( bitmaskToStringTemplate, { { "bitmaskName", bitmaskName } } );
  }
  else
  {
    static const std::string bitmaskToStringTemplate = R"(
  VULKAN_HPP_INLINE std::string to_string( ${bitmaskName} value )
  {
    if ( !value )
      return "{}";

    std::string result;
${toStringChecks}
    return "{ " + result.substr( 0, result.size() - 3 ) + " }";
  }
)";

    std::string toStringChecks;
    std::string previousEnter, previousLeave;
    for ( auto const & value : bitmaskBitsIt->second.values )
    {
      auto [enter, leave]   = generateProtection( value.extension, value.protect );
      std::string valueName = generateEnumValueName( bitmaskBitsIt->first, value.name, true, m_tags );
      if ( value.singleBit )
      {
        toStringChecks += ( ( previousEnter != enter ) ? ( previousLeave + enter ) : "" ) + "    if ( value & " + enumName + "::" + valueName +
                          " ) result += \"" + valueName.substr( 1 ) + " | \";\n";
      }
      previousEnter = enter;
      previousLeave = leave;
    }
    if ( !previousLeave.empty() )
    {
      assert( previousLeave.ends_with( "\n" ) );
      toStringChecks += previousLeave;
      previousLeave.resize( previousLeave.size() - strlen( "\n" ) );
    }

    str += replaceWithMap( bitmaskToStringTemplate, { { "bitmaskName", bitmaskName }, { "toStringChecks", toStringChecks } } );
  }

  return str;
}

std::string VulkanHppGenerator::generateCallArgumentsEnhanced( CommandData const &      commandData,
                                                               size_t                   initialSkipCount,
                                                               bool                     nonConstPointerAsNullptr,
                                                               std::set<size_t> const & singularParams,
                                                               std::set<size_t> const & templatedParams,
                                                               bool                     raiiHandleMemberFunction ) const
{
  assert( initialSkipCount <= commandData.params.size() );
  std::string arguments;
  bool        encounteredArgument = false;
  if ( raiiHandleMemberFunction )
  {
    switch ( initialSkipCount )
    {
      case 1:
        assert( isHandleType( commandData.params[0].type.type ) && commandData.params[0].type.isValue() );
        assert( commandData.params[0].arraySizes.empty() && commandData.params[0].len.empty() );
        assert( commandData.params[0].type.type == commandData.handle );
        arguments           = "static_cast<" + commandData.handle + ">( m_" + startLowerCase( stripPrefix( commandData.handle, "Vk" ) ) + " )";
        encounteredArgument = true;
        break;
      case 2:
        {
          assert( isHandleType( commandData.params[0].type.type ) && commandData.params[0].type.isValue() );
          assert( commandData.params[0].arraySizes.empty() && commandData.params[0].len.empty() );
          assert( commandData.params[0].type.type == commandData.handle );
          auto handleIt = m_handles.find( commandData.params[1].type.type );
          assert( handleIt != m_handles.end() );
          arguments = "static_cast<" + commandData.handle + ">( m_" + startLowerCase( stripPrefix( commandData.handle, "Vk" ) ) + " )";

          assert( commandData.params[1].type.isValue() && commandData.params[1].arraySizes.empty() && commandData.params[1].len.empty() );
          arguments += ", static_cast<" + commandData.params[1].type.type + ">( m_" +
                       generateRAIIHandleConstructorParamName( handleIt->first, handleIt->second.destructorIt ) + " )";
          encounteredArgument = true;
        }
        break;
    }
  }
  else
  {
    for ( size_t i = 0; i < initialSkipCount; ++i )
    {
      if ( encounteredArgument )
      {
        arguments += ", ";
      }
      assert( isHandleType( commandData.params[i].type.type ) && commandData.params[i].type.isValue() );
      assert( commandData.params[i].arraySizes.empty() && commandData.params[i].len.empty() );
      arguments += "m_" + startLowerCase( stripPrefix( commandData.params[i].type.type, "Vk" ) );
      encounteredArgument = true;
    }
  }
  for ( size_t i = initialSkipCount; i < commandData.params.size(); ++i )
  {
    if ( encounteredArgument )
    {
      arguments += ", ";
    }
    arguments += generateCallArgumentEnhanced( commandData.params, i, nonConstPointerAsNullptr, singularParams, templatedParams );
    encounteredArgument = true;
  }
  return arguments;
}

std::string VulkanHppGenerator::generateCallArgumentsRAIIFactory( std::vector<ParamData> const & params,
                                                                  size_t                         initialSkipCount,
                                                                  std::set<size_t> const &       skippedParams,
                                                                  std::set<size_t> const &       singularParams ) const
{
  assert( initialSkipCount <= params.size() );
  std::string arguments = "*this";
  // skip the last parameter!
  for ( size_t i = initialSkipCount; i < params.size() - 1; ++i )
  {
    if ( skippedParams.find( i ) == skippedParams.end() )
    {
      std::string argument = params[i].name;
      if ( !params[i].type.isValue() )
      {
        argument = startLowerCase( stripPrefix( argument, "p" ) );
        if ( singularParams.find( i ) != singularParams.end() )
        {
          argument = stripPluralS( argument );
        }
      }
      else
      {
        assert( singularParams.find( i ) == singularParams.end() );
      }
      arguments += ", " + argument;
    }
  }
  return arguments;
}

std::string VulkanHppGenerator::generateCallArgumentsStandard( std::string const & handle, std::vector<ParamData> const & params ) const
{
  std::string arguments;
  bool        encounteredArgument = false;
  for ( auto const & param : params )
  {
    if ( encounteredArgument )
    {
      arguments += ", ";
    }
    if ( ( param.type.type == handle ) && param.type.isValue() )
    {
      assert( param.arraySizes.empty() && param.len.empty() );
      arguments += "m_" + startLowerCase( stripPrefix( param.type.type, "Vk" ) );
    }
    else
    {
      std::string argument = param.name;
      if ( param.type.type.starts_with( "Vk" ) )
      {
        if ( !param.arraySizes.empty() )
        {
          assert( param.arraySizes.size() == 1 );
          assert( param.type.isValue() );
          assert( param.type.postfix.empty() );
          argument = "reinterpret_cast<" + param.type.compose( "" ) + " *>( " + argument + " )";
        }
        else if ( param.type.isValue() )
        {
          argument = "static_cast<" + param.type.type + ">( " + argument + " )";
        }
        else
        {
          assert( !param.type.postfix.empty() );
          argument = "reinterpret_cast<" + param.type.compose( "" ) + ">( " + argument + " )";
        }
      }
      arguments += argument;
    }
    encounteredArgument = true;
  }
  return arguments;
}

std::string VulkanHppGenerator::generateCallArgumentEnhanced( std::vector<ParamData> const & params,
                                                              size_t                         paramIndex,
                                                              bool                           nonConstPointerAsNullptr,
                                                              std::set<size_t> const &       singularParams,
                                                              std::set<size_t> const &       templatedParams ) const
{
  std::string       argument;
  ParamData const & param = params[paramIndex];
  if ( param.type.isConstPointer() || ( specialPointerTypes.find( param.type.type ) != specialPointerTypes.end() ) )
  {
    // parameter is a const-pointer or one of the special pointer types that are considered to be const-pointers
    argument = generateCallArgumentEnhancedConstPointer( param, paramIndex, singularParams, templatedParams );
  }
  else if ( param.type.isNonConstPointer() && ( specialPointerTypes.find( param.type.type ) == specialPointerTypes.end() ) )
  {
    // parameter is a non-const pointer and none of the special pointer types, that are considered const-pointers
    argument = generateCallArgumentEnhancedNonConstPointer( param, paramIndex, nonConstPointerAsNullptr, singularParams );
  }
  else
  {
    argument = generateCallArgumentEnhancedValue( params, paramIndex, singularParams );
  }
  assert( !argument.empty() );
  return argument;
}

std::string VulkanHppGenerator::generateCallArgumentEnhancedConstPointer( ParamData const &        param,
                                                                          size_t                   paramIndex,
                                                                          std::set<size_t> const & singularParams,
                                                                          std::set<size_t> const & templatedParams ) const
{
  std::string argument;
  std::string name = startLowerCase( stripPrefix( param.name, "p" ) );
  if ( isHandleType( param.type.type ) && param.type.isValue() )
  {
    assert( !param.optional );
    // if at all, this is the first argument, and it's the implicitly provided member handle
    assert( paramIndex == 0 );
    assert( param.arraySizes.empty() && param.len.empty() );
    argument = "m_" + startLowerCase( stripPrefix( param.type.type, "Vk" ) );
  }
  else if ( param.len.empty() )
  {
    // this const-pointer parameter has no length, that is it's a const-pointer to a single value
    if ( param.type.type == "void" )
    {
      assert( !param.optional );
      argument = ( templatedParams.find( paramIndex ) == templatedParams.end() )
                 ? param.name
                 : "reinterpret_cast<" + param.type.compose( "VULKAN_HPP_NAMESPACE" ) + ">( &" + name + " )";
    }
    else if ( param.optional )
    {
      argument = "static_cast<" + param.type.compose( "VULKAN_HPP_NAMESPACE" ) + ">( " + name + " )";
    }
    else
    {
      argument = "&" + name;
    }
    if ( param.type.type.starts_with( "Vk" ) )
    {
      argument = "reinterpret_cast<" + param.type.compose( "" ) + ">( " + argument + " )";
    }
  }
  else if ( param.len == "null-terminated" )
  {
    // this const-pointer parameter is "null-terminated", that is it's a string
    assert( ( param.type.type == "char" ) && param.arraySizes.empty() );
    if ( param.optional )
    {
      argument = name + " ? " + name + "->c_str() : nullptr";
    }
    else
    {
      argument = name + ".c_str()";
    }
  }
  else
  {
    // this const-pointer parameter has some explicit length
    if ( singularParams.find( paramIndex ) != singularParams.end() )
    {
      assert( !param.optional );
      argument = "&" + stripPluralS( name );
    }
    else
    {
      // this const-parameter is represented by some array, where data() also works with no data (optional)
      argument = name + ".data()";
    }
    if ( param.type.type.starts_with( "Vk" ) || ( param.type.type == "void" ) )
    {
      argument = "reinterpret_cast<" + param.type.compose( "" ) + ">( " + argument + " )";
    }
  }
  return argument;
}

std::string VulkanHppGenerator::generateCallArgumentEnhancedNonConstPointer( ParamData const &        param,
                                                                             size_t                   paramIndex,
                                                                             bool                     nonConstPointerAsNullptr,
                                                                             std::set<size_t> const & singularParams ) const
{
  std::string argument;
  std::string name = startLowerCase( stripPrefix( param.name, "p" ) );
  if ( param.len.empty() )
  {
    assert( param.arraySizes.empty() );
    if ( param.type.type.starts_with( "Vk" ) )
    {
      argument = "reinterpret_cast<" + param.type.compose( "" ) + ">( &" + name + " )";
    }
    else
    {
      assert( !param.optional );
      argument = "&" + name;
    }
  }
  else
  {
    // the non-const pointer has a len -> it will be represented by some array
    assert( param.arraySizes.empty() );
    if ( nonConstPointerAsNullptr )
    {
      argument = "nullptr";
    }
    else
    {
      if ( singularParams.find( paramIndex ) != singularParams.end() )
      {
        argument = "&" + stripPluralS( name );
      }
      else
      {
        // get the data of the array, which also covers no data -> no need to look at param.optional
        argument = name + ".data()";
      }
      if ( param.type.type.starts_with( "Vk" ) || ( param.type.type == "void" ) )
      {
        argument = "reinterpret_cast<" + param.type.compose( "" ) + ">( " + argument + " )";
      }
    }
  }
  return argument;
}

std::string VulkanHppGenerator::generateCallArgumentEnhancedValue( std::vector<ParamData> const & params,
                                                                   size_t                         paramIndex,
                                                                   std::set<size_t> const &       singularParams ) const
{
  std::string       argument;
  ParamData const & param = params[paramIndex];
  assert( param.len.empty() );
  if ( param.type.type.starts_with( "Vk" ) )
  {
    if ( param.arraySizes.empty() )
    {
      auto pointerIt = std::find_if( params.begin(), params.end(), [&param]( ParamData const & pd ) { return pd.len == param.name; } );
      if ( pointerIt != params.end() )
      {
        assert( !param.optional );
        argument = startLowerCase( stripPrefix( pointerIt->name, "p" ) ) + ".size()";
        if ( pointerIt->type.type == "void" )
        {
          argument += " * sizeof( " + stripPrefix( pointerIt->name, "p" ) + "Type )";
        }
      }
      else
      {
        argument = "static_cast<" + param.type.compose( "" ) + ">( " + param.name + " )";
      }
      assert( std::find_if( params.begin(), params.end(), [&param]( ParamData const & pd ) { return pd.stride == param.name; } ) == params.end() );
    }
    else
    {
      assert( !param.optional );
      assert( param.arraySizes.size() == 1 );
      assert( param.type.prefix == "const" );
      argument = "reinterpret_cast<" + param.type.compose( "" ) + " *>( " + param.name + " )";
    }
  }
  else
  {
    auto pointerIt = std::find_if( params.begin(), params.end(), [&param]( ParamData const & pd ) { return pd.len == param.name; } );
    if ( pointerIt != params.end() )
    {
      // this parameter is the len of some other -> replace it with that parameter's size
      assert( param.arraySizes.empty() );
      assert( ( param.type.type == "size_t" ) || ( param.type.type == "uint32_t" ) );
      if ( singularParams.find( paramIndex ) == singularParams.end() )
      {
        argument = startLowerCase( stripPrefix( pointerIt->name, "p" ) ) + ".size()";
        if ( pointerIt->type.type == "void" )
        {
          argument += " * sizeof( " + stripPrefix( pointerIt->name, "p" ) + "Type )";
        }
      }
      else
      {
        if ( pointerIt->type.type == "void" )
        {
          argument = "sizeof( " + stripPrefix( pointerIt->name, "p" ) + "Type )";
        }
        else
        {
          argument = "1";
        }
      }
    }
    else
    {
      assert( !param.optional );
      assert( param.arraySizes.size() <= 1 );
      pointerIt = std::find_if( params.begin(), params.end(), [&param]( ParamData const & pd ) { return pd.stride == param.name; } );
      if ( pointerIt != params.end() )
      {
        // this parameter is the stride of some other -> replace it with that parameter's stride
        assert( param.arraySizes.empty() );
        assert( param.type.type == "uint32_t" );
        argument = startLowerCase( stripPrefix( pointerIt->name, "p" ) ) + ".stride()";
      }
      else
      {
        argument = param.name;
      }
    }
  }
  return argument;
}

std::string VulkanHppGenerator::generateCallSequence( std::string const &                       name,
                                                      CommandData const &                       commandData,
                                                      std::vector<size_t> const &               returnParams,
                                                      std::map<size_t, VectorParamData> const & vectorParams,
                                                      size_t                                    initialSkipCount,
                                                      std::set<size_t> const &                  singularParams,
                                                      std::set<size_t> const &                  templatedParams,
                                                      bool                                      chained,
                                                      bool                                      raii ) const
{
  std::string dispatcher = raii ? "getDispatcher()->" : "d.";
  // if at least one returnParam is a size value of a vector param (and no singular params), we need two calls
  if ( singularParams.empty() &&
       ( std::find_if( returnParams.begin(),
                       returnParams.end(),
                       [&vectorParams]( size_t rp )
                       {
                         return ( std::find_if( vectorParams.begin(), vectorParams.end(), [rp]( auto const & vp ) { return vp.second.lenParam == rp; } ) !=
                                  vectorParams.end() );
                       } ) != returnParams.end() ) )
  {
    auto vectorParamIt = vectorParams.find( returnParams[1] );
    assert( ( vectorParamIt != vectorParams.end() ) && ( vectorParamIt->second.lenParam == returnParams[0] ) );

    std::string firstCallArguments  = generateCallArgumentsEnhanced( commandData, initialSkipCount, true, {}, templatedParams, raii );
    std::string secondCallArguments = generateCallArgumentsEnhanced( commandData, initialSkipCount, false, {}, templatedParams, raii );
    std::string vectorName          = startLowerCase( stripPrefix( commandData.params[vectorParamIt->first].name, "p" ) );
    std::string vectorSize          = startLowerCase( stripPrefix( commandData.params[vectorParamIt->second.lenParam].name, "p" ) );

    if ( chained )
    {
      assert( vectorParams.size() == 1 );
      // chained data needs some more handling!!
      std::string vectorElementType = stripPostfix( commandData.params[vectorParamIt->first].type.compose( "VULKAN_HPP_NAMESPACE" ), " *" );

      if ( commandData.returnType == "VkResult" )
      {
        const std::string callSequenceTemplate = R"(VkResult result;
    do
    {
      result = ${dispatcher}${vkCommand}( ${firstCallArguments} );
      if ( ( result == VK_SUCCESS ) && ${counterName} )
      {
        structureChains.resize( ${counterName} );
        ${vectorName}.resize( ${counterName} );
        for ( ${counterType} i = 0; i < ${counterName}; i++ )
        {
          ${vectorName}[i].pNext = structureChains[i].template get<${vectorElementType}>().pNext;
        }
        result = ${dispatcher}${vkCommand}( ${secondCallArguments} );
      }
    } while ( result == VK_INCOMPLETE );)";

        return replaceWithMap( callSequenceTemplate,
                               { { "counterName", startLowerCase( stripPrefix( commandData.params[vectorParamIt->second.lenParam].name, "p" ) ) },
                                 { "counterType", commandData.params[vectorParamIt->second.lenParam].type.type },
                                 { "dispatcher", dispatcher },
                                 { "firstCallArguments", firstCallArguments },
                                 { "secondCallArguments", secondCallArguments },
                                 { "vectorElementType", vectorElementType },
                                 { "vectorName", vectorName },
                                 { "vkCommand", name } } );
      }
      else
      {
        const std::string callSequenceTemplate =
          R"(${dispatcher}${vkCommand}( ${firstCallArguments} );
    structureChains.resize( ${counterName} );
    ${vectorName}.resize( ${counterName} );
    for ( ${counterType} i = 0; i < ${counterName}; i++ )
    {
      ${vectorName}[i].pNext = structureChains[i].template get<${vectorElementType}>().pNext;
    }
    ${dispatcher}${vkCommand}( ${secondCallArguments} );)";

        return replaceWithMap( callSequenceTemplate,
                               { { "counterName", startLowerCase( stripPrefix( commandData.params[vectorParamIt->second.lenParam].name, "p" ) ) },
                                 { "counterType", commandData.params[vectorParamIt->second.lenParam].type.type },
                                 { "dispatcher", dispatcher },
                                 { "firstCallArguments", firstCallArguments },
                                 { "secondCallArguments", secondCallArguments },
                                 { "vectorElementType", vectorElementType },
                                 { "vectorName", vectorName },
                                 { "vkCommand", name } } );
      }
    }
    else if ( commandData.returnType == "VkResult" )
    {
      assert( ( commandData.successCodes.size() == 2 ) && ( commandData.successCodes[0] == "VK_SUCCESS" ) &&
              ( commandData.successCodes[1] == "VK_INCOMPLETE" ) );

      std::string resizes;
      for ( auto const & vp : vectorParams )
      {
        assert( ( std::find( returnParams.begin(), returnParams.end(), vp.first ) != returnParams.end() ) &&
                ( std::find( returnParams.begin(), returnParams.end(), vp.second.lenParam ) != returnParams.end() ) );
        resizes += startLowerCase( stripPrefix( commandData.params[vp.first].name, "p" ) ) + ".resize( " +
                   startLowerCase( stripPrefix( commandData.params[vp.second.lenParam].name, "p" ) ) + " );\n";
      }
      resizes.pop_back();

      std::string const callSequenceTemplate = R"(VkResult result;
    do
    {
      result = ${dispatcher}${vkCommand}( ${firstCallArguments} );
      if ( ( result == VK_SUCCESS ) && ${counterName} )
      {
        ${resizes}
        result = ${dispatcher}${vkCommand}( ${secondCallArguments} );
      }
    } while ( result == VK_INCOMPLETE );)";

      return replaceWithMap( callSequenceTemplate,
                             { { "counterName", startLowerCase( stripPrefix( commandData.params[vectorParamIt->second.lenParam].name, "p" ) ) },
                               { "dispatcher", dispatcher },
                               { "firstCallArguments", firstCallArguments },
                               { "secondCallArguments", secondCallArguments },
                               { "resizes", resizes },
                               { "vkCommand", name } } );
    }
    else
    {
      // no need to enumerate here, just two calls
      assert( commandData.returnType == "void" );
      std::string const callSequenceTemplate = R"(${dispatcher}${vkCommand}( ${firstCallArguments} );
    ${vectorName}.resize( ${vectorSize} );
    ${dispatcher}${vkCommand}( ${secondCallArguments} );)";

      return replaceWithMap( callSequenceTemplate,
                             { { "dispatcher", dispatcher },
                               { "firstCallArguments", firstCallArguments },
                               { "secondCallArguments", secondCallArguments },
                               { "vectorName", vectorName },
                               { "vectorSize", vectorSize },
                               { "vkCommand", name } } );
    }
  }
  else
  {
    std::string const callSequenceTemplate = R"(${resultAssignment}${dispatcher}${vkCommand}( ${callArguments} );)";

    std::string callArguments    = generateCallArgumentsEnhanced( commandData, initialSkipCount, false, singularParams, templatedParams, raii );
    std::string resultAssignment = generateResultAssignment( commandData );

    return replaceWithMap(
      callSequenceTemplate,
      { { "callArguments", callArguments }, { "dispatcher", dispatcher }, { "resultAssignment", resultAssignment }, { "vkCommand", name } } );
  }
}

std::string VulkanHppGenerator::generateCommand( std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition ) const
{
  std::string str;
  if ( commandData.returnType == "VkResult" )
  {
    assert( !commandData.successCodes.empty() );
    if ( commandData.successCodes.size() == 1 )
    {
      if ( commandData.errorCodes.empty() )
      {
        str = generateCommandResultSingleSuccessNoErrors( name, commandData, initialSkipCount, definition );
      }
      else
      {
        str = generateCommandResultSingleSuccessWithErrors( name, commandData, initialSkipCount, definition );
      }
    }
    else
    {
      if ( commandData.errorCodes.empty() )
      {
        str = generateCommandResultMultiSuccessNoErrors( name, commandData, initialSkipCount, definition );
      }
      else
      {
        str = generateCommandResultMultiSuccessWithErrors( name, commandData, initialSkipCount, definition );
      }
    }
  }
  else if ( commandData.returnType == "void" )
  {
    std::vector<size_t> returnParams = determineReturnParams( commandData.params );
    switch ( returnParams.size() )
    {
      case 0: str = generateCommandVoid0Return( name, commandData, initialSkipCount, definition ); break;
      case 1: str = generateCommandVoid1Return( name, commandData, initialSkipCount, definition, returnParams[0] ); break;
      case 2: str = generateCommandVoid2Return( name, commandData, initialSkipCount, definition, returnParams ); break;
    }
  }
  else
  {
    str = generateCommandValue( name, commandData, initialSkipCount, definition );
  }

  if ( str.empty() )
  {
    throw std::runtime_error( "Never encountered a function like <" + name + "> !" );
  }
  return str;
}

std::string VulkanHppGenerator::generateCommandDefinitions() const
{
  const std::string commandDefinitionsTemplate = R"(
  //===========================
  //=== COMMAND Definitions ===
  //===========================

${commandDefinitions}
)";

  std::string           commandDefinitions;
  std::set<std::string> listedCommands;  // some commands are listed with more than one extension!
  for ( auto const & feature : m_features )
  {
    commandDefinitions += generateCommandDefinitions( feature.second.requireData, listedCommands, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    commandDefinitions += generateCommandDefinitions( extIt.second->second.requireData, listedCommands, extIt.second->first );
  }

  return replaceWithMap( commandDefinitionsTemplate, { { "commandDefinitions", commandDefinitions } } );
}

std::string VulkanHppGenerator::generateCommandDefinitions( std::vector<RequireData> const & requireData,
                                                            std::set<std::string> &          listedCommands,
                                                            std::string const &              title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & command : require.commands )
    {
      if ( listedCommands.insert( command ).second )
      {
        auto commandIt = m_commands.find( command );
        assert( commandIt != m_commands.end() );
        str += generateCommandDefinitions( command, commandIt->second.handle );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateCommandDefinitions( std::string const & command, std::string const & handle ) const
{
  auto commandIt = m_commands.find( command );
  assert( commandIt != m_commands.end() );

  std::string str = "\n" + generateCommand( commandIt->first, commandIt->second, handle.empty() ? 0 : 1, true );

  // special handling for destroy functions, filter out alias functions
  std::string commandName = generateCommandName( commandIt->first, commandIt->second.params, 1, m_tags, false, false );
  if ( commandIt->second.alias.empty() &&
       ( ( ( commandIt->first.substr( 2, 7 ) == "Destroy" ) && ( commandName != "destroy" ) ) || ( commandIt->first.substr( 2, 4 ) == "Free" ) ||
         ( commandIt->first == "vkReleasePerformanceConfigurationINTEL" ) ) )
  {
    CommandData commandData = commandIt->second;
    assert( ( 1 < commandData.params.size() ) && ( commandData.params[0].type.type == handle ) );
    commandData.params[1].optional = false;  // make sure, the object to destroy/free/release is not optional in the shortened version!

    std::string destroyCommandString = generateCommand( commandIt->first, commandData, handle.empty() ? 0 : 1, true );
    std::string shortenedName;
    if ( commandIt->first.substr( 2, 7 ) == "Destroy" )
    {
      shortenedName = "destroy";
    }
    else if ( commandIt->first.substr( 2, 4 ) == "Free" )
    {
      shortenedName = "free";
    }
    else
    {
      assert( commandIt->first == "vkReleasePerformanceConfigurationINTEL" );
      shortenedName = "release";
    }
    size_t pos = destroyCommandString.find( commandName );
    while ( pos != std::string::npos )
    {
      destroyCommandString.replace( pos, commandName.length(), shortenedName );
      pos = destroyCommandString.find( commandName, pos );
    }

    // special handling for "free", to prevent interfering with MSVC debug free!
    if ( shortenedName == "free" )
    {
      std::string toEncloseString = stripPrefix( handle, "Vk" ) + "::free";
      std::string enclosedString  = "( " + toEncloseString + " )";
      pos                         = destroyCommandString.find( toEncloseString );
      while ( pos != std::string::npos )
      {
        destroyCommandString.replace( pos, toEncloseString.length(), enclosedString );
        pos = destroyCommandString.find( toEncloseString, pos + enclosedString.length() );
      }
    }

    // we need to remove the default argument for the first argument, to prevent ambiguities!
    assert( 1 < commandIt->second.params.size() );
    pos = destroyCommandString.find( commandIt->second.params[1].name );  // skip the standard version of the function
    assert( pos != std::string::npos );
    pos = destroyCommandString.find( commandIt->second.params[1].name,
                                     pos + 1 );  // get the argument to destroy in the advanced version
    assert( pos != std::string::npos );
    pos = destroyCommandString.find( " VULKAN_HPP_DEFAULT_ARGUMENT_ASSIGNMENT", pos );
    if ( pos != std::string::npos )
    {
      destroyCommandString.erase( pos, strlen( " VULKAN_HPP_DEFAULT_ARGUMENT_ASSIGNMENT" ) );
    }
    str += "\n" + destroyCommandString;
  }
  return str;
}

std::string VulkanHppGenerator::generateCommandEnhanced( std::string const &                       name,
                                                         CommandData const &                       commandData,
                                                         size_t                                    initialSkipCount,
                                                         bool                                      definition,
                                                         std::map<size_t, VectorParamData> const & vectorParams,
                                                         std::vector<size_t> const &               returnParams,
                                                         bool                                      singular,
                                                         bool                                      withAllocator,
                                                         bool                                      chained,
                                                         bool                                      unique ) const
{
  assert( vectorParams.empty() || ( vectorParams.begin()->second.lenParam != INVALID_INDEX ) );
  assert( !singular || !returnParams.empty() );  // if singular is true, then there is at least one returnParam !

  std::set<size_t> skippedParams = determineSkippedParams( commandData.params, initialSkipCount, vectorParams, returnParams, singular );
  // special handling for vkGetMemoryHostPointerPropertiesEXT: here, we really need to stick with the const void * parameter !
  std::set<size_t> templatedParams = ( name == "vkGetMemoryHostPointerPropertiesEXT" ) ? std::set<size_t>() : determineVoidPointerParams( commandData.params );
  std::set<size_t> singularParams  = singular ? determineSingularParams( returnParams[0], vectorParams ) : std::set<size_t>();
  std::pair<bool, std::map<size_t, std::vector<size_t>>> vectorSizeCheck =
    needsVectorSizeCheck( commandData.params, vectorParams, returnParams, singularParams );
  bool enumerating = determineEnumeration( vectorParams, returnParams );

  std::vector<std::string> dataTypes = determineDataTypes( commandData.params, vectorParams, returnParams, templatedParams );
  std::string              dataType  = combineDataTypes( vectorParams, returnParams, singular, enumerating, dataTypes, unique, false );

  std::string argumentTemplates = generateArgumentTemplates( commandData.params, returnParams, vectorParams, templatedParams, chained, false );
  auto [allocatorTemplates, uniqueHandleAllocatorTemplates] =
    generateAllocatorTemplates( returnParams, dataTypes, vectorParams, definition, singular, unique, chained );
  std::string typenameCheck  = generateTypenameCheck( returnParams, vectorParams, definition, dataTypes, singular, withAllocator, unique, chained );
  std::string nodiscard      = generateNoDiscard( !returnParams.empty(), 1 < commandData.successCodes.size(), 1 < commandData.errorCodes.size() );
  std::string returnType     = generateReturnType( commandData, returnParams, vectorParams, unique, chained, false, dataType );
  std::string className      = initialSkipCount ? stripPrefix( commandData.params[initialSkipCount - 1].type.type, "Vk" ) : "";
  std::string classSeparator = commandData.handle.empty() ? "" : "::";
  std::string commandName    = generateCommandName( name, commandData.params, initialSkipCount, m_tags, singular, unique );
  std::string argumentList   = generateArgumentListEnhanced(
    commandData.params, returnParams, vectorParams, skippedParams, singularParams, templatedParams, definition, withAllocator, chained, true );
  std::string constString    = commandData.handle.empty() ? "" : " const";
  std::string noexceptString = generateNoExcept( commandData.errorCodes, returnParams, vectorParams, singular, vectorSizeCheck.first, false );

  if ( definition )
  {
    std::string vectorSizeCheckString =
      vectorSizeCheck.first ? generateVectorSizeCheck( name, commandData, initialSkipCount, vectorSizeCheck.second, skippedParams, false ) : "";
    std::string returnVariable   = generateReturnVariable( commandData, returnParams, vectorParams, chained, singular );
    std::string dataDeclarations = generateDataDeclarations( commandData,
                                                             returnParams,
                                                             vectorParams,
                                                             templatedParams,
                                                             singular,
                                                             withAllocator,
                                                             chained,
                                                             unique,
                                                             false,
                                                             dataTypes,
                                                             dataType,
                                                             returnType,
                                                             returnVariable );
    std::string dataPreparation  = generateDataPreparation(
      commandData, initialSkipCount, returnParams, vectorParams, templatedParams, singular, withAllocator, unique, chained, enumerating );
    std::string dataSizeChecks = generateDataSizeChecks( commandData, returnParams, dataTypes, vectorParams, templatedParams, singular );
    std::string callSequence =
      generateCallSequence( name, commandData, returnParams, vectorParams, initialSkipCount, singularParams, templatedParams, chained, false );
    std::string resultCheck     = generateResultCheck( commandData, className, classSeparator, commandName, enumerating );
    std::string returnStatement = generateReturnStatement( name,
                                                           commandData,
                                                           returnVariable,
                                                           returnType,
                                                           dataType,
                                                           initialSkipCount,
                                                           returnParams.empty() ? INVALID_INDEX : returnParams[0],
                                                           unique,
                                                           enumerating,
                                                           false );

    std::string const functionTemplate =
      R"(  template <${argumentTemplates}${allocatorTemplates}typename Dispatch${uniqueHandleAllocatorTemplates}${typenameCheck}>
  ${nodiscard}VULKAN_HPP_INLINE ${returnType} ${className}${classSeparator}${commandName}( ${argumentList} )${const}${noexcept}
  {
    VULKAN_HPP_ASSERT( d.getVkHeaderVersion() == VK_HEADER_VERSION );
${vectorSizeCheck}
    ${dataSizeChecks}
    ${dataDeclarations}
    ${callSequence}
    ${resultCheck}
    ${dataPreparation}
    ${returnStatement}
  })";

    return replaceWithMap( functionTemplate,
                           { { "allocatorTemplates", allocatorTemplates },
                             { "argumentList", argumentList },
                             { "argumentTemplates", argumentTemplates },
                             { "callSequence", callSequence },
                             { "className", className },
                             { "classSeparator", classSeparator },
                             { "commandName", commandName },
                             { "const", constString },
                             { "dataDeclarations", dataDeclarations },
                             { "dataPreparation", dataPreparation },
                             { "dataSizeChecks", dataSizeChecks },
                             { "nodiscard", nodiscard },
                             { "noexcept", noexceptString },
                             { "resultCheck", resultCheck },
                             { "returnStatement", returnStatement },
                             { "returnType", returnType },
                             { "typenameCheck", typenameCheck },
                             { "uniqueHandleAllocatorTemplates", uniqueHandleAllocatorTemplates },
                             { "vectorSizeCheck", vectorSizeCheckString } } );
  }
  else
  {
    std::string const functionTemplate =
      R"(    template <${argumentTemplates}${allocatorTemplates}typename Dispatch = VULKAN_HPP_DEFAULT_DISPATCHER_TYPE${uniqueHandleAllocatorTemplates}${typenameCheck}>
    ${nodiscard}${returnType} ${commandName}( ${argumentList} )${const}${noexcept};)";

    return replaceWithMap( functionTemplate,
                           { { "allocatorTemplates", allocatorTemplates },
                             { "argumentList", argumentList },
                             { "argumentTemplates", argumentTemplates },
                             { "commandName", commandName },
                             { "const", commandData.handle.empty() ? "" : " const" },
                             { "nodiscard", nodiscard },
                             { "noexcept", noexceptString },
                             { "returnType", returnType },
                             { "typenameCheck", typenameCheck },
                             { "uniqueHandleAllocatorTemplates", uniqueHandleAllocatorTemplates } } );
  }
}

std::string VulkanHppGenerator::generateCommandName( std::string const &            vulkanCommandName,
                                                     std::vector<ParamData> const & params,
                                                     size_t                         initialSkipCount,
                                                     std::set<std::string> const &  tags,
                                                     bool                           singular,
                                                     bool                           unique ) const
{
  std::string commandName( startLowerCase( stripPrefix( vulkanCommandName, "vk" ) ) );
  for ( size_t i = initialSkipCount - 1; i < initialSkipCount; --i )  // count down to zero, then wrap around and stop
  {
    std::string const & argumentType = params[i].type.type;
    std::string         searchName   = stripPrefix( argumentType, "Vk" );
    std::string         argumentTag  = findTag( tags, argumentType );
    if ( !argumentTag.empty() )
    {
      searchName = stripPostfix( searchName, argumentTag );
    }
    size_t pos = commandName.find( searchName );
    if ( pos == std::string::npos )
    {
      searchName = startLowerCase( searchName );
      pos        = commandName.find( searchName );
    }
    if ( pos != std::string::npos )
    {
      size_t len = searchName.length();
      if ( commandName.find( searchName + "s" ) == pos )
      {
        // filter out any plural of the searchName as well!
        ++len;
      }
      commandName.erase( pos, len );
    }
    else if ( ( searchName == "commandBuffer" ) && commandName.starts_with( "cmd" ) )
    {
      commandName.erase( 0, 3 );
      pos = 0;
    }
    if ( pos == 0 )
    {
      commandName = startLowerCase( commandName );
    }
    std::string commandTag = findTag( tags, commandName );
    if ( !argumentTag.empty() && ( argumentTag == commandTag ) )
    {
      commandName = stripPostfix( commandName, argumentTag );
    }
  }
  if ( singular )
  {
    commandName = stripPluralS( commandName );
  }
  if ( unique )
  {
    commandName += "Unique";
  }
  return commandName;
}

std::string VulkanHppGenerator::generateCommandResultMultiSuccessNoErrors( std::string const & name,
                                                                           CommandData const & commandData,
                                                                           size_t              initialSkipCount,
                                                                           bool                definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandData.params );
  switch ( returnParams.size() )
  {
    case 0: return generateCommandResultMultiSuccessNoErrors0Return( name, commandData, initialSkipCount, definition ); break;
    case 2: return generateCommandResultMultiSuccessNoErrors2Return( name, commandData, initialSkipCount, definition, returnParams ); break;
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultMultiSuccessNoErrors0Return( std::string const & name,
                                                                                  CommandData const & commandData,
                                                                                  size_t              initialSkipCount,
                                                                                  bool                definition ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  if ( vectorParams.empty() )
  {
    std::vector<size_t> constPointerParams = determineConstPointerParams( commandData.params );
    if ( constPointerParams.empty() )
    {
      return generateCommandSetStandardOrEnhanced(
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, {}, {}, false, false, false, false ) );
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultMultiSuccessNoErrors2Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, std::vector<size_t> const & returnParams ) const
{
  if ( ( commandData.successCodes.size() == 2 ) && ( commandData.successCodes[0] == "VK_SUCCESS" ) && ( commandData.successCodes[1] == "VK_INCOMPLETE" ) )
  {
    if ( ( commandData.params[returnParams[0]].type.type == "size_t" ) || ( commandData.params[returnParams[0]].type.type == "uint32_t" ) )
    {
      if ( ( commandData.params[returnParams[1]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[1]].type.type ) &&
           !isStructureChainAnchor( commandData.params[returnParams[1]].type.type ) )
      {
        std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
        if ( vectorParams.size() == 1 )
        {
          if ( returnParams[0] == vectorParams.begin()->second.lenParam )
          {
            if ( returnParams[1] == vectorParams.begin()->first )
            {
              return generateCommandSetStandardEnhancedWithAllocator(
                definition,
                generateCommandStandard( name, commandData, initialSkipCount, definition ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, false, false ) );
            }
          }
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultMultiSuccessWithErrors( std::string const & name,
                                                                             CommandData const & commandData,
                                                                             size_t              initialSkipCount,
                                                                             bool                definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandData.params );
  switch ( returnParams.size() )
  {
    case 0: return generateCommandResultWithErrors0Return( name, commandData, initialSkipCount, definition ); break;
    case 1: return generateCommandResultMultiSuccessWithErrors1Return( name, commandData, initialSkipCount, definition, returnParams[0] ); break;
    case 2: return generateCommandResultMultiSuccessWithErrors2Return( name, commandData, initialSkipCount, definition, returnParams ); break;
    case 3: return generateCommandResultMultiSuccessWithErrors3Return( name, commandData, initialSkipCount, definition, returnParams ); break;
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultMultiSuccessWithErrors1Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, size_t returnParam ) const
{
  if ( commandData.params[returnParam].type.type == "void" )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
    if ( vectorParams.size() == 1 )
    {
      if ( returnParam == vectorParams.begin()->first )
      {
        if ( commandData.params[vectorParams.begin()->second.lenParam].type.isValue() )
        {
          return generateCommandSetStandardEnhancedSingular(
            definition,
            generateCommandStandard( name, commandData, initialSkipCount, definition ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, false ) );
        }
      }
    }
  }
  else if ( isHandleType( commandData.params[returnParam].type.type ) )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
    if ( vectorParams.size() == 2 )
    {
      if ( returnParam == std::next( vectorParams.begin() )->first )
      {
        if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
        {
          if ( commandData.params[vectorParams.begin()->second.lenParam].type.type == "uint32_t" )
          {
            if ( isStructureChainAnchor( commandData.params[vectorParams.begin()->first].type.type ) )
            {
              return generateCommandSetStandardEnhancedWithAllocatorSingularUnique(
                definition,
                generateCommandStandard( name, commandData, initialSkipCount, definition ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, true, false, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, true ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, true, false, true ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, true ) );
            }
          }
        }
      }
    }
  }
  else if ( !isStructureChainAnchor( commandData.params[returnParam].type.type ) )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
    if ( vectorParams.empty() )
    {
      return generateCommandSetStandardEnhanced(
        definition,
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ) );
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultMultiSuccessWithErrors2Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, std::vector<size_t> const & returnParams ) const
{
  if ( ( commandData.successCodes.size() == 2 ) && ( commandData.successCodes[0] == "VK_SUCCESS" ) && ( commandData.successCodes[1] == "VK_INCOMPLETE" ) )
  {
    if ( ( commandData.params[returnParams[0]].type.type == "size_t" ) || ( commandData.params[returnParams[0]].type.type == "uint32_t" ) )
    {
      if ( isStructureChainAnchor( commandData.params[returnParams[1]].type.type ) )
      {
        std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
        if ( vectorParams.size() == 1 )
        {
          if ( returnParams[0] == vectorParams.begin()->second.lenParam )
          {
            if ( returnParams[1] == vectorParams.begin()->first )
            {
              return generateCommandSetStandardEnhancedWithAllocatorChained(
                definition,
                generateCommandStandard( name, commandData, initialSkipCount, definition ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, false, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, true, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, true, false ) );
            }
          }
        }
      }
      else
      {
        std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
        if ( vectorParams.size() == 1 )
        {
          if ( returnParams[0] == vectorParams.begin()->second.lenParam )
          {
            if ( returnParams[1] == vectorParams.begin()->first )
            {
              return generateCommandSetStandardEnhancedWithAllocator(
                definition,
                generateCommandStandard( name, commandData, initialSkipCount, definition ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, false, false ) );
            }
          }
        }
      }
    }
    else if ( ( commandData.params[returnParams[0]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[0]].type.type ) &&
              !isStructureChainAnchor( commandData.params[returnParams[0]].type.type ) )
    {
      if ( ( commandData.params[returnParams[1]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[1]].type.type ) &&
           !isStructureChainAnchor( commandData.params[returnParams[1]].type.type ) )
      {
        std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
        if ( vectorParams.empty() )
        {
          return generateCommandSetStandardEnhanced(
            definition,
            generateCommandStandard( name, commandData, initialSkipCount, definition ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ) );
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultMultiSuccessWithErrors3Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, std::vector<size_t> const & returnParams ) const
{
  if ( commandData.params[returnParams[0]].type.type == "uint32_t" )
  {
    if ( ( commandData.params[returnParams[1]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[1]].type.type ) &&
         !isStructureChainAnchor( commandData.params[returnParams[1]].type.type ) )
    {
      if ( ( commandData.params[returnParams[2]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[2]].type.type ) &&
           !isStructureChainAnchor( commandData.params[returnParams[2]].type.type ) )
      {
        std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
        if ( vectorParams.size() == 2 )
        {
          if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
          {
            if ( returnParams[0] == vectorParams.begin()->second.lenParam )
            {
              if ( returnParams[1] == vectorParams.begin()->first )
              {
                if ( returnParams[2] == std::next( vectorParams.begin() )->first )
                {
                  return generateCommandSetStandardEnhancedWithAllocator(
                    definition,
                    generateCommandStandard( name, commandData, initialSkipCount, definition ),
                    generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ),
                    generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, false, false ) );
                }
              }
            }
          }
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessNoErrors( std::string const & name,
                                                                            CommandData const & commandData,
                                                                            size_t              initialSkipCount,
                                                                            bool                definition ) const
{
  std::vector<size_t>               returnParams = determineReturnParams( commandData.params );
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  switch ( returnParams.size() )
  {
    case 0:
      switch ( vectorParams.size() )
      {
        case 0:
          {
            std::vector<size_t> constPointerParams = determineConstPointerParams( commandData.params );
            if ( constPointerParams.empty() )
            {
              return generateCommandSetStandardOrEnhanced(
                generateCommandStandard( name, commandData, initialSkipCount, definition ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, {}, {}, false, false, false, false ) );
            }
          }
          break;
        case 1:
          if ( commandData.params[vectorParams.begin()->second.lenParam].type.isValue() )
          {
            if ( isHandleType( commandData.params[vectorParams.begin()->first].type.type ) )
            {
              return generateCommandSetStandardEnhanced(
                definition,
                generateCommandStandard( name, commandData, initialSkipCount, definition ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, {}, false, false, false, false ) );
            }
          }
          break;
      }
      break;
    case 1:
      if ( vectorParams.empty() )
      {
        if ( ( commandData.params[returnParams[0]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[0]].type.type ) &&
             !isStructureChainAnchor( commandData.params[returnParams[0]].type.type ) )
        {
          return generateCommandSetStandardEnhanced(
            definition,
            generateCommandStandard( name, commandData, initialSkipCount, definition ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ) );
        }
      }
      break;
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors( std::string const & name,
                                                                              CommandData const & commandData,
                                                                              size_t              initialSkipCount,
                                                                              bool                definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandData.params );
  switch ( returnParams.size() )
  {
    case 0: return generateCommandResultWithErrors0Return( name, commandData, initialSkipCount, definition ); break;
    case 1: return generateCommandResultSingleSuccessWithErrors1Return( name, commandData, initialSkipCount, definition, returnParams[0] ); break;
    case 2: return generateCommandResultSingleSuccessWithErrors2Return( name, commandData, initialSkipCount, definition, returnParams ); break;
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, size_t returnParam ) const
{
  if ( commandData.params[returnParam].type.type == "void" )
  {
    return generateCommandResultSingleSuccessWithErrors1ReturnVoid( name, commandData, initialSkipCount, definition, returnParam );
  }
  else if ( isHandleType( commandData.params[returnParam].type.type ) )
  {
    return generateCommandResultSingleSuccessWithErrors1ReturnHandle( name, commandData, initialSkipCount, definition, returnParam );
  }
  else if ( isStructureChainAnchor( commandData.params[returnParam].type.type ) )
  {
    return generateCommandResultSingleSuccessWithErrors1ReturnChain( name, commandData, initialSkipCount, definition, returnParam );
  }
  else
  {
    return generateCommandResultSingleSuccessWithErrors1ReturnValue( name, commandData, initialSkipCount, definition, returnParam );
  }
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1ReturnChain(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, size_t returnParam ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  if ( vectorParams.empty() )
  {
    return generateCommandSetStandardEnhancedChained(
      definition,
      generateCommandStandard( name, commandData, initialSkipCount, definition ),
      generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
      generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, true, false ) );
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1ReturnHandle(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, size_t returnParam ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  switch ( vectorParams.size() )
  {
    case 0:
      return generateCommandSetStandardEnhancedUnique(
        definition,
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, true ) );
      break;
    case 1:
      return generateCommandResultSingleSuccessWithErrors1ReturnHandle1Vector(
        name, commandData, initialSkipCount, definition, returnParam, *vectorParams.begin() );
      break;
    case 2:
      return generateCommandResultSingleSuccessWithErrors1ReturnHandle2Vector( name, commandData, initialSkipCount, definition, returnParam, vectorParams );
      break;
  }
  return "";
}

std::string
  VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1ReturnHandle1Vector( std::string const &                        name,
                                                                                        CommandData const &                        commandData,
                                                                                        size_t                                     initialSkipCount,
                                                                                        bool                                       definition,
                                                                                        size_t                                     returnParam,
                                                                                        std::pair<size_t, VectorParamData> const & vectorParamIndex ) const
{
  if ( returnParam == vectorParamIndex.first )
  {
    if ( isLenByStructMember( commandData.params[vectorParamIndex.first].len, commandData.params[vectorParamIndex.second.lenParam] ) )
    {
      return generateCommandSetStandardEnhancedWithAllocatorUnique(
        definition,
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, { vectorParamIndex }, { returnParam }, false, false, false, false ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, { vectorParamIndex }, { returnParam }, false, true, false, false ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, { vectorParamIndex }, { returnParam }, false, false, false, true ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, { vectorParamIndex }, { returnParam }, false, true, false, true ) );
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1ReturnHandle2Vector( std::string const &                       name,
                                                                                                  CommandData const &                       commandData,
                                                                                                  size_t                                    initialSkipCount,
                                                                                                  bool                                      definition,
                                                                                                  size_t                                    returnParam,
                                                                                                  std::map<size_t, VectorParamData> const & vectorParams ) const
{
  if ( returnParam == std::next( vectorParams.begin() )->first )
  {
    if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
    {
      if ( commandData.params[vectorParams.begin()->second.lenParam].type.isValue() )
      {
        if ( isStructureChainAnchor( commandData.params[vectorParams.begin()->first].type.type ) )
        {
          return generateCommandSetStandardEnhancedWithAllocatorSingularUnique(
            definition,
            generateCommandStandard( name, commandData, initialSkipCount, definition ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, true, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, true ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, true, false, true ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, true ) );
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1ReturnValue(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, size_t returnParam ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  switch ( vectorParams.size() )
  {
    case 0:
      return generateCommandSetStandardEnhanced(
        definition,
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ) );
    case 2:
      return generateCommandResultSingleSuccessWithErrors1ReturnValue2Vectors( name, commandData, initialSkipCount, definition, returnParam, vectorParams );
      break;
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1ReturnValue2Vectors( std::string const &                       name,
                                                                                                  CommandData const &                       commandData,
                                                                                                  size_t                                    initialSkipCount,
                                                                                                  bool                                      definition,
                                                                                                  size_t                                    returnParam,
                                                                                                  std::map<size_t, VectorParamData> const & vectorParams ) const
{
  if ( returnParam == std::next( vectorParams.begin() )->first )
  {
    if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
    {
      if ( commandData.params[vectorParams.begin()->second.lenParam].type.type == "uint32_t" )
      {
        if ( ( commandData.params[vectorParams.begin()->first].type.type != "void" ) &&
             !isHandleType( commandData.params[vectorParams.begin()->first].type.type ) &&
             !isStructureChainAnchor( commandData.params[vectorParams.begin()->first].type.type ) )
        {
          return generateCommandSetStandardEnhancedWithAllocatorSingular(
            definition,
            generateCommandStandard( name, commandData, initialSkipCount, definition ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, true, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, false ) );
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors1ReturnVoid(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, size_t returnParam ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  switch ( vectorParams.size() )
  {
    case 0:
      return generateCommandSetStandardEnhanced(
        definition,
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ) );
      break;
    case 1:
      if ( returnParam == vectorParams.begin()->first )
      {
        if ( commandData.params[vectorParams.begin()->second.lenParam].type.isValue() )
        {
          return generateCommandSetStandardEnhancedSingular(
            definition,
            generateCommandStandard( name, commandData, initialSkipCount, definition ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, false ) );
        }
      }
      break;
    case 2:
      if ( returnParam == std::next( vectorParams.begin() )->first )
      {
        if ( vectorParams.begin()->second.lenParam != std::next( vectorParams.begin() )->second.lenParam )
        {
          if ( commandData.params[vectorParams.begin()->second.lenParam].type.isValue() )
          {
            if ( isHandleType( commandData.params[vectorParams.begin()->first].type.type ) )
            {
              if ( commandData.params[std::next( vectorParams.begin() )->second.lenParam].type.isValue() )
              {
                return generateCommandSetStandardEnhancedSingular(
                  definition,
                  generateCommandStandard( name, commandData, initialSkipCount, definition ),
                  generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
                  generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, false ) );
              }
            }
          }
        }
      }
      break;
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultSingleSuccessWithErrors2Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, std::vector<size_t> const & returnParams ) const
{
  if ( ( commandData.params[returnParams[0]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[0]].type.type ) &&
       !isStructureChainAnchor( commandData.params[returnParams[0]].type.type ) )
  {
    if ( ( commandData.params[returnParams[1]].type.type != "void" ) && !isHandleType( commandData.params[returnParams[1]].type.type ) &&
         !isStructureChainAnchor( commandData.params[returnParams[1]].type.type ) )
    {
      std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
      if ( vectorParams.size() == 2 )
      {
        if ( returnParams[0] == std::next( vectorParams.begin() )->first )
        {
          if ( vectorParams.find( returnParams[1] ) == vectorParams.end() )
          {
            assert( ( returnParams[1] != vectorParams.begin()->second.lenParam ) && ( returnParams[1] != std::next( vectorParams.begin() )->second.lenParam ) );
            if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
            {
              if ( commandData.params[vectorParams.begin()->second.lenParam].type.isValue() )
              {
                if ( ( commandData.params[vectorParams.begin()->first].type.type != "void" ) &&
                     !isHandleType( commandData.params[vectorParams.begin()->first].type.type ) &&
                     !isStructureChainAnchor( commandData.params[vectorParams.begin()->first].type.type ) )
                {
                  return generateCommandSetStandardEnhancedWithAllocatorSingular(
                    definition,
                    generateCommandStandard( name, commandData, initialSkipCount, definition ),
                    generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ),
                    generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, false, false ),
                    generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, true, false, false, false ) );
                }
              }
            }
          }
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandResultWithErrors0Return( std::string const & name,
                                                                        CommandData const & commandData,
                                                                        size_t              initialSkipCount,
                                                                        bool                definition ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  if ( vectorParams.empty() && determineConstPointerParams( commandData.params ).empty() )
  {
    return generateCommandSetStandardOrEnhanced(
      generateCommandStandard( name, commandData, initialSkipCount, definition ),
      generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, {}, false, false, false, false ) );
  }
  else if ( allVectorSizesSupported( commandData.params, vectorParams ) )
  {
    return generateCommandSetStandardEnhanced(
      definition,
      generateCommandStandard( name, commandData, initialSkipCount, definition ),
      generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, {}, false, false, false, false ) );
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandSetStandard( std::string const & standard ) const
{
  const std::string commandTemplate = R"(
${commandStandard}
)";

  return replaceWithMap( commandTemplate, std::map<std::string, std::string>( { { "commandStandard", standard } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhanced( bool definition, std::string const & standard, std::string const & enhanced ) const
{
  const std::string commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>(
                           { { "commandEnhanced", enhanced }, { "commandStandard", standard }, { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedChained( bool                definition,
                                                                           std::string const & standard,
                                                                           std::string const & enhanced,
                                                                           std::string const & enhancedChained ) const
{
  std::string const commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
${commandEnhancedChained}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedChained", enhancedChained },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedSingular( bool                definition,
                                                                            std::string const & standard,
                                                                            std::string const & enhanced,
                                                                            std::string const & enhancedSingular ) const
{
  std::string const commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
${commandEnhancedSingular}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedSingular", enhancedSingular },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedUnique( bool                definition,
                                                                          std::string const & standard,
                                                                          std::string const & enhanced,
                                                                          std::string const & enhancedUnique ) const
{
  std::string const commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
#  ifndef VULKAN_HPP_NO_SMART_HANDLE
${commandEnhancedUnique}
#  endif /*VULKAN_HPP_NO_SMART_HANDLE*/
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedUnique", enhancedUnique },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedWithAllocator( bool                definition,
                                                                                 std::string const & standard,
                                                                                 std::string const & enhanced,
                                                                                 std::string const & enhancedWithAllocator ) const
{
  const std::string commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
${commandEnhancedWithAllocator}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedWithAllocator", enhancedWithAllocator },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedWithAllocatorChained( bool                definition,
                                                                                        std::string const & standard,
                                                                                        std::string const & enhanced,
                                                                                        std::string const & enhancedWithAllocator,
                                                                                        std::string const & enhancedChained,
                                                                                        std::string const & enhancedChainedWithAllocator ) const
{
  std::string const commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
${commandEnhancedWithAllocator}${newlineOnDefinition}
${commandEnhancedChained}${newlineOnDefinition}
${commandEnhancedChainedWithAllocator}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedChained", enhancedChained },
                                                               { "commandEnhancedChainedWithAllocator", enhancedChainedWithAllocator },
                                                               { "commandEnhancedWithAllocator", enhancedWithAllocator },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedWithAllocatorSingular( bool                definition,
                                                                                         std::string const & standard,
                                                                                         std::string const & enhanced,
                                                                                         std::string const & enhancedWithAllocator,
                                                                                         std::string const & enhancedSingular ) const
{
  std::string const commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
${commandEnhancedWithAllocator}${newlineOnDefinition}
${commandEnhancedSingular}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedSingular", enhancedSingular },
                                                               { "commandEnhancedWithAllocator", enhancedWithAllocator },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedWithAllocatorSingularUnique( bool                definition,
                                                                                               std::string const & standard,
                                                                                               std::string const & enhanced,
                                                                                               std::string const & enhancedWithAllocator,
                                                                                               std::string const & enhancedSingular,
                                                                                               std::string const & enhancedUnique,
                                                                                               std::string const & enhancedUniqueWithAllocator,
                                                                                               std::string const & enhancedUniqueSingular ) const
{
  std::string const commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
${commandEnhancedWithAllocator}${newlineOnDefinition}
${commandEnhancedSingular}${newlineOnDefinition}
#  ifndef VULKAN_HPP_NO_SMART_HANDLE
${commandEnhancedUnique}${newlineOnDefinition}
${commandEnhancedUniqueWithAllocator}${newlineOnDefinition}
${commandEnhancedUniqueSingular}
#  endif /*VULKAN_HPP_NO_SMART_HANDLE*/
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedSingular", enhancedSingular },
                                                               { "commandEnhancedUnique", enhancedUnique },
                                                               { "commandEnhancedUniqueSingular", enhancedUniqueSingular },
                                                               { "commandEnhancedUniqueWithAllocator", enhancedUniqueWithAllocator },
                                                               { "commandEnhancedWithAllocator", enhancedWithAllocator },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardEnhancedWithAllocatorUnique( bool                definition,
                                                                                       std::string const & standard,
                                                                                       std::string const & enhanced,
                                                                                       std::string const & enhancedWithAllocator,
                                                                                       std::string const & enhancedUnique,
                                                                                       std::string const & enhancedUniqueWithAllocator ) const
{
  std::string const commandTemplate = R"(
${commandStandard}${newlineOnDefinition}
#ifndef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandEnhanced}${newlineOnDefinition}
${commandEnhancedWithAllocator}${newlineOnDefinition}
#  ifndef VULKAN_HPP_NO_SMART_HANDLE
${commandEnhancedUnique}${newlineOnDefinition}
${commandEnhancedUniqueWithAllocator}
#  endif /*VULKAN_HPP_NO_SMART_HANDLE*/
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate,
                         std::map<std::string, std::string>( { { "commandEnhanced", enhanced },
                                                               { "commandEnhancedUnique", enhancedUnique },
                                                               { "commandEnhancedUniqueWithAllocator", enhancedUniqueWithAllocator },
                                                               { "commandEnhancedWithAllocator", enhancedWithAllocator },
                                                               { "commandStandard", standard },
                                                               { "newlineOnDefinition", definition ? "\n" : "" } } ) );
}

std::string VulkanHppGenerator::generateCommandSetStandardOrEnhanced( std::string const & standard, std::string const & enhanced ) const
{
  const std::string commandTemplate = R"(
#ifdef VULKAN_HPP_DISABLE_ENHANCED_MODE
${commandStandard}
#else
${commandEnhanced}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

  return replaceWithMap( commandTemplate, std::map<std::string, std::string>( { { "commandEnhanced", enhanced }, { "commandStandard", standard } } ) );
}

std::string
  VulkanHppGenerator::generateCommandStandard( std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition ) const
{
  std::set<size_t> skippedParams = determineSkippedParams( commandData.params, initialSkipCount, {}, {}, false );

  std::string argumentList = generateArgumentListStandard( commandData.params, skippedParams );
  std::string commandName  = generateCommandName( name, commandData.params, initialSkipCount, m_tags, false, false );
  std::string nodiscard    = ( 1 < commandData.successCodes.size() + commandData.errorCodes.size() ) ? "VULKAN_HPP_NODISCARD " : "";
  std::string returnType   = stripPrefix( commandData.returnType, "Vk" );

  if ( definition )
  {
    std::string functionBody = "d." + name + "( " + generateCallArgumentsStandard( commandData.handle, commandData.params ) + " )";
    if ( commandData.returnType.starts_with( "Vk" ) )
    {
      functionBody = "return static_cast<" + returnType + ">( " + functionBody + " )";
    }
    else if ( commandData.returnType != "void" )
    {
      functionBody = "return " + functionBody;
    }

    std::string const functionTemplate =
      R"(  template <typename Dispatch>
  ${nodiscard}VULKAN_HPP_INLINE ${returnType} ${className}${classSeparator}${commandName}( ${argumentList} )${const} VULKAN_HPP_NOEXCEPT
  {
    VULKAN_HPP_ASSERT( d.getVkHeaderVersion() == VK_HEADER_VERSION );
    ${functionBody};
  })";

    return replaceWithMap( functionTemplate,
                           { { "argumentList", argumentList },
                             { "className", initialSkipCount ? stripPrefix( commandData.params[initialSkipCount - 1].type.type, "Vk" ) : "" },
                             { "classSeparator", commandData.handle.empty() ? "" : "::" },
                             { "commandName", commandName },
                             { "const", commandData.handle.empty() ? "" : " const" },
                             { "functionBody", functionBody },
                             { "nodiscard", nodiscard },
                             { "returnType", returnType } } );
  }
  else
  {
    std::string const functionTemplate =
      R"(    template <typename Dispatch = VULKAN_HPP_DEFAULT_DISPATCHER_TYPE>
    ${nodiscard}${returnType} ${commandName}( ${argumentList} VULKAN_HPP_DEFAULT_DISPATCHER_ASSIGNMENT )${const} VULKAN_HPP_NOEXCEPT;)";

    return replaceWithMap( functionTemplate,
                           { { "argumentList", argumentList },
                             { "commandName", commandName },
                             { "const", commandData.handle.empty() ? "" : " const" },
                             { "nodiscard", nodiscard },
                             { "returnType", returnType } } );
  }
}

std::string
  VulkanHppGenerator::generateCommandValue( std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandData.params );
  if ( returnParams.empty() )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
    if ( vectorParams.empty() )
    {
      if ( determineConstPointerParams( commandData.params ).empty() )
      {
        return generateCommandSetStandard( generateCommandStandard( name, commandData, initialSkipCount, definition ) );
      }
      else
      {
        return generateCommandSetStandardEnhanced(
          definition,
          generateCommandStandard( name, commandData, initialSkipCount, definition ),
          generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ) );
      }
    }
  }
  return "";
}

std::string
  VulkanHppGenerator::generateCommandVoid0Return( std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  if ( vectorParams.empty() && determineConstPointerParams( commandData.params ).empty() )
  {
    return generateCommandSetStandard( generateCommandStandard( name, commandData, initialSkipCount, definition ) );
  }
  else if ( allVectorSizesSupported( commandData.params, vectorParams ) )
  {
    // All the vectorParams have a counter by value, of type "uint32_t", "VkDeviceSize", or "VkSampleCountFlagBits" (!)
    return generateCommandSetStandardEnhanced(
      definition,
      generateCommandStandard( name, commandData, initialSkipCount, definition ),
      generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, {}, false, false, false, false ) );
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandVoid1Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, size_t returnParam ) const
{
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
  if ( commandData.params[returnParam].type.postfix == "**" )
  {
    // get a pointer to something
    if ( commandData.params[returnParam].type.type == "void" )
    {
      if ( vectorParams.empty() )
      {
        return generateCommandSetStandardEnhanced(
          definition,
          generateCommandStandard( name, commandData, initialSkipCount, definition ),
          generateCommandEnhanced( name, commandData, initialSkipCount, definition, {}, { returnParam }, false, false, false, false ) );
      }
    }
  }
  else if ( isHandleType( commandData.params[returnParam].type.type ) )
  {
    if ( vectorParams.empty() )
    {
      return generateCommandSetStandardEnhanced(
        definition,
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, {}, { returnParam }, false, false, false, false ) );
    }
  }
  else if ( isStructureChainAnchor( commandData.params[returnParam].type.type ) )
  {
    if ( vectorParams.empty() )
    {
      return generateCommandSetStandardEnhancedChained(
        definition,
        generateCommandStandard( name, commandData, initialSkipCount, definition ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, {}, { returnParam }, false, false, false, false ),
        generateCommandEnhanced( name, commandData, initialSkipCount, definition, {}, { returnParam }, false, false, true, false ) );
    }
  }
  else if ( commandData.params[returnParam].type.type == "void" )
  {
    switch ( vectorParams.size() )
    {
      case 0:
        return generateCommandSetStandardEnhanced(
          definition,
          generateCommandStandard( name, commandData, initialSkipCount, definition ),
          generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ) );
      case 1:
        if ( returnParam == vectorParams.begin()->first )
        {
          if ( name == stripPluralS( name ) )
          {
            return generateCommandSetStandardEnhanced(
              definition,
              generateCommandStandard( name, commandData, initialSkipCount, definition ),
              generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, true, false, false, false ) );
          }
        }
        break;
    }
  }
  else
  {
    switch ( vectorParams.size() )
    {
      case 0:
        return generateCommandSetStandardEnhanced(
          definition,
          generateCommandStandard( name, commandData, initialSkipCount, definition ),
          generateCommandEnhanced( name, commandData, initialSkipCount, definition, {}, { returnParam }, false, false, false, false ) );
        break;
      case 1:
        if ( returnParam == vectorParams.begin()->first )
        {
          // you get a vector of stuff, with the size being one of the parameters
          return generateCommandSetStandardEnhancedWithAllocator(
            definition,
            generateCommandStandard( name, commandData, initialSkipCount, definition ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ),
            generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, true, false, false ) );
        }
        else
        {
          if ( !isHandleType( commandData.params[vectorParams.begin()->first].type.type ) &&
               !isStructureChainAnchor( commandData.params[vectorParams.begin()->first].type.type ) &&
               ( commandData.params[vectorParams.begin()->first].type.type != "void" ) )
          {
            if ( isLenByStructMember( commandData.params[vectorParams.begin()->first].len, commandData.params[vectorParams.begin()->second.lenParam] ) )
            {
              return generateCommandSetStandardEnhanced(
                definition,
                generateCommandStandard( name, commandData, initialSkipCount, definition ),
                generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, { returnParam }, false, false, false, false ) );
            }
          }
        }
        break;
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateCommandVoid2Return(
  std::string const & name, CommandData const & commandData, size_t initialSkipCount, bool definition, std::vector<size_t> const & returnParams ) const
{
  if ( commandData.params[returnParams[0]].type.type == "uint32_t" )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandData.params );
    if ( vectorParams.size() == 1 )
    {
      if ( returnParams[0] == vectorParams.begin()->second.lenParam )
      {
        if ( returnParams[1] == vectorParams.begin()->first )
        {
          if ( isStructureChainAnchor( commandData.params[returnParams[1]].type.type ) )
          {
            return generateCommandSetStandardEnhancedWithAllocatorChained(
              definition,
              generateCommandStandard( name, commandData, initialSkipCount, definition ),
              generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ),
              generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, false, false ),
              generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, true, false ),
              generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, true, false ) );
          }
          else if ( !isHandleType( commandData.params[returnParams[1]].type.type ) )
          {
            return generateCommandSetStandardEnhancedWithAllocator(
              definition,
              generateCommandStandard( name, commandData, initialSkipCount, definition ),
              generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, false, false, false ),
              generateCommandEnhanced( name, commandData, initialSkipCount, definition, vectorParams, returnParams, false, true, false, false ) );
          }
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateConstexprString( std::string const & structName ) const
{
  // structs with a VkBaseInStructure and VkBaseOutStructure can't be a constexpr!
  bool isConstExpression = ( structName != "VkBaseInStructure" ) && ( structName != "VkBaseOutStructure" );
  return isConstExpression ? ( std::string( "VULKAN_HPP_CONSTEXPR" ) + ( ( containsUnion( structName ) || containsArray( structName ) ) ? "_14 " : " " ) ) : "";
}

std::string VulkanHppGenerator::generateDataDeclarations( CommandData const &                       commandData,
                                                          std::vector<size_t> const &               returnParams,
                                                          std::map<size_t, VectorParamData> const & vectorParams,
                                                          std::set<size_t> const &                  templatedParams,
                                                          bool                                      singular,
                                                          bool                                      withAllocator,
                                                          bool                                      chained,
                                                          bool                                      unique,
                                                          bool                                      raii,
                                                          std::vector<std::string> const &          dataTypes,
                                                          std::string const &                       dataType,
                                                          std::string const &                       returnType,
                                                          std::string const &                       returnVariable ) const
{
  assert( dataTypes.size() == returnParams.size() );

  switch ( returnParams.size() )
  {
    case 0: return "";  // no returnParams -> no data declarations
    case 1:
      return generateDataDeclarations1Return(
        commandData, returnParams, vectorParams, templatedParams, singular, withAllocator, chained, unique, dataTypes, dataType, returnType, returnVariable );
    case 2:
      assert( !unique );
      return generateDataDeclarations2Returns(
        commandData, returnParams, vectorParams, singular, withAllocator, chained, raii, dataTypes, dataType, returnVariable );
    case 3:
      assert( ( vectorParams.size() == 2 ) && ( returnParams[0] == vectorParams.begin()->second.lenParam ) &&
              ( returnParams[1] == vectorParams.begin()->first ) && ( returnParams[2] == std::next( vectorParams.begin() )->first ) &&
              ( returnParams[0] == std::next( vectorParams.begin() )->second.lenParam ) && templatedParams.empty() && !chained && !singular && !unique );
      return generateDataDeclarations3Returns( commandData, returnParams, withAllocator, raii, dataTypes );
    default: assert( false ); return "";
  }
}

std::string VulkanHppGenerator::generateDataDeclarations1Return( CommandData const &                       commandData,
                                                                 std::vector<size_t> const &               returnParams,
                                                                 std::map<size_t, VectorParamData> const & vectorParams,
                                                                 std::set<size_t> const &                  templatedParams,
                                                                 bool                                      singular,
                                                                 bool                                      withAllocator,
                                                                 bool                                      chained,
                                                                 bool                                      unique,
                                                                 std::vector<std::string> const &          dataTypes,
                                                                 std::string const &                       dataType,
                                                                 std::string const &                       returnType,
                                                                 std::string const &                       returnVariable ) const
{
  auto vectorParamIt = vectorParams.find( returnParams[0] );
  if ( !chained )
  {
    if ( ( vectorParamIt == vectorParams.end() ) || singular )
    {
      std::string const dataDeclarationsTemplate = R"(${returnType} ${returnVariable};)";

      return replaceWithMap( dataDeclarationsTemplate, { { "returnType", dataType }, { "returnVariable", returnVariable } } );
    }
    else
    {
      std::string allocator       = stripPrefix( dataTypes[0], "VULKAN_HPP_NAMESPACE::" ) + "Allocator";
      std::string vectorAllocator = ( withAllocator && !unique ) ? ( ", " + startLowerCase( allocator ) ) : "";
      std::string vectorSize      = getVectorSize( commandData.params, vectorParams, returnParams[0], dataTypes[0], templatedParams );

      std::string const dataDeclarationsTemplate = R"(${dataType} ${returnVariable}( ${vectorSize}${vectorAllocator} );)";

      return replaceWithMap(
        dataDeclarationsTemplate,
        { { "dataType", dataType }, { "returnVariable", returnVariable }, { "vectorAllocator", vectorAllocator }, { "vectorSize", vectorSize } } );
    }
  }
  else
  {
    assert( ( vectorParamIt == vectorParams.end() ) || singular );

    std::string dataVariable = startLowerCase( stripPrefix( commandData.params[returnParams[0]].name, "p" ) );

    std::string const dataDeclarationsTemplate = R"(${returnType} ${returnVariable};
    ${dataType} & ${dataVariable} = ${returnVariable}.template get<${dataType}>();)";

    return replaceWithMap( dataDeclarationsTemplate,
                           { { "dataType", dataTypes[0] },
                             { "dataVariable", dataVariable },
                             { "returnType", ( commandData.returnType == "void" ) ? returnType : "StructureChain<X, Y, Z...>" },
                             { "returnVariable", returnVariable } } );
  }
}

std::string VulkanHppGenerator::generateDataDeclarations2Returns( CommandData const &                       commandData,
                                                                  std::vector<size_t> const &               returnParams,
                                                                  std::map<size_t, VectorParamData> const & vectorParams,
                                                                  bool                                      singular,
                                                                  bool                                      withAllocator,
                                                                  bool                                      chained,
                                                                  bool                                      raii,
                                                                  std::vector<std::string> const &          dataTypes,
                                                                  std::string const &                       dataType,
                                                                  std::string const &                       returnVariable ) const
{
  switch ( vectorParams.size() )
  {
    case 0:
      assert( !singular && !chained );
      {
        std::string firstDataVariable  = startLowerCase( stripPrefix( commandData.params[returnParams[0]].name, "p" ) );
        std::string secondDataVariable = startLowerCase( stripPrefix( commandData.params[returnParams[1]].name, "p" ) );

        std::string const dataDeclarationTemplate = R"(std::pair<${firstDataType},${secondDataType}> data;
    ${firstDataType} & ${firstDataVariable} = data.first;
    ${secondDataType} & ${secondDataVariable} = data.second;)";

        return replaceWithMap( dataDeclarationTemplate,
                               { { "firstDataType", dataTypes[0] },
                                 { "firstDataVariable", firstDataVariable },
                                 { "secondDataType", dataTypes[1] },
                                 { "secondDataVariable", secondDataVariable } } );
      }
      break;
    case 1:
      assert( ( returnParams[0] == vectorParams.begin()->second.lenParam ) && ( returnParams[1] == vectorParams.begin()->first ) && !singular );
      {
        std::string counterVariable = startLowerCase( stripPrefix( commandData.params[returnParams[0]].name, "p" ) );
        if ( !chained )
        {
          std::string vectorAllocator = withAllocator ? ( "( " + startLowerCase( stripPrefix( dataTypes[1], "VULKAN_HPP_NAMESPACE::" ) ) + "Allocator )" ) : "";

          std::string const dataDeclarationTemplate = R"(${returnType} ${returnVariable}${vectorAllocator};
    ${counterType} ${counterVariable};)";

          return replaceWithMap( dataDeclarationTemplate,
                                 { { "counterType", dataTypes[0] },
                                   { "counterVariable", counterVariable },
                                   { "returnType", dataType },
                                   { "returnVariable", returnVariable },
                                   { "vectorAllocator", vectorAllocator } } );
        }
        else
        {
          std::string structureChainAllocator   = raii ? "" : ", StructureChainAllocator";
          std::string structureChainInitializer = withAllocator ? ( "( structureChainAllocator )" ) : "";
          std::string vectorVariable            = startLowerCase( stripPrefix( commandData.params[returnParams[1]].name, "p" ) );

          std::string const dataDeclarationTemplate =
            R"(std::vector<StructureChain${structureChainAllocator}> structureChains${structureChainInitializer};
    std::vector<${vectorElementType}> ${vectorVariable};
    ${counterType} ${counterVariable};)";

          return replaceWithMap( dataDeclarationTemplate,
                                 {
                                   { "counterType", dataTypes[0] },
                                   { "counterVariable", counterVariable },
                                   { "structureChainAllocator", structureChainAllocator },
                                   { "structureChainInitializer", structureChainInitializer },
                                   { "vectorElementType", dataTypes[1] },
                                   { "vectorVariable", vectorVariable },
                                 } );
        }
      }
      break;
    case 2:
      assert( ( returnParams[0] == std::next( vectorParams.begin() )->first ) && ( vectorParams.find( returnParams[1] ) == vectorParams.end() ) && !chained );
      {
        std::string firstDataVariable  = startLowerCase( stripPrefix( commandData.params[returnParams[0]].name, "p" ) );
        std::string secondDataVariable = startLowerCase( stripPrefix( commandData.params[returnParams[1]].name, "p" ) );
        if ( singular )
        {
          firstDataVariable = stripPluralS( firstDataVariable );

          std::string const dataDeclarationTemplate = R"(std::pair<${firstDataType},${secondDataType}> data;
    ${firstDataType} & ${firstDataVariable} = data.first;
    ${secondDataType} & ${secondDataVariable} = data.second;)";

          return replaceWithMap( dataDeclarationTemplate,
                                 { { "firstDataType", dataTypes[0] },
                                   { "firstDataVariable", firstDataVariable },
                                   { "secondDataType", dataTypes[1] },
                                   { "secondDataVariable", secondDataVariable } } );
        }
        else
        {
          std::string allocatorType       = raii ? "" : ( startUpperCase( stripPrefix( dataTypes[0], "VULKAN_HPP_NAMESPACE::" ) ) + "Allocator" );
          std::string allocateInitializer = withAllocator ? ( ", " + startLowerCase( allocatorType ) ) : "";
          if ( !raii )
          {
            allocatorType = ", " + allocatorType;
          }
          std::string vectorSize = startLowerCase( stripPrefix( commandData.params[vectorParams.begin()->first].name, "p" ) ) + ".size()";

          std::string const dataDeclarationTemplate =
            R"(std::pair<std::vector<${firstDataType}${allocatorType}>,${secondDataType}> data( std::piecewise_construct, std::forward_as_tuple( ${vectorSize}${allocateInitializer} ), std::forward_as_tuple( 0 ) );
    std::vector<${firstDataType}${allocatorType}> & ${firstDataVariable} = data.first;
    ${secondDataType} & ${secondDataVariable} = data.second;)";

          return replaceWithMap( dataDeclarationTemplate,
                                 { { "allocateInitializer", allocateInitializer },
                                   { "allocatorType", allocatorType },
                                   { "firstDataType", dataTypes[0] },
                                   { "firstDataVariable", firstDataVariable },
                                   { "secondDataType", dataTypes[1] },
                                   { "secondDataVariable", secondDataVariable },
                                   { "vectorSize", vectorSize } } );
        }
      }
      break;
    default: assert( false ); return "";
  }
}

std::string VulkanHppGenerator::generateDataDeclarations3Returns(
  CommandData const & commandData, std::vector<size_t> const & returnParams, bool withAllocator, bool raii, std::vector<std::string> const & dataTypes ) const
{
  std::string counterVariable      = startLowerCase( stripPrefix( commandData.params[returnParams[0]].name, "p" ) );
  std::string firstVectorVariable  = startLowerCase( stripPrefix( commandData.params[returnParams[1]].name, "p" ) );
  std::string secondVectorVariable = startLowerCase( stripPrefix( commandData.params[returnParams[2]].name, "p" ) );
  std::string firstVectorAllocatorType, secondVectorAllocatorType, pairConstructor;
  if ( !raii )
  {
    firstVectorAllocatorType  = startUpperCase( stripPrefix( dataTypes[1], "VULKAN_HPP_NAMESPACE::" ) ) + "Allocator";
    secondVectorAllocatorType = startUpperCase( stripPrefix( dataTypes[2], "VULKAN_HPP_NAMESPACE::" ) ) + "Allocator";
    pairConstructor           = withAllocator ? ( "( std::piecewise_construct, std::forward_as_tuple( " + startLowerCase( firstVectorAllocatorType ) +
                                        " ), std::forward_as_tuple( " + startLowerCase( secondVectorAllocatorType ) + " ) )" )
                                              : "";
    firstVectorAllocatorType  = ", " + firstVectorAllocatorType;
    secondVectorAllocatorType = ", " + secondVectorAllocatorType;
  }

  std::string const dataDeclarationsTemplate =
    R"(std::pair<std::vector<${firstVectorElementType}${firstVectorAllocatorType}>, std::vector<${secondVectorElementType}${secondVectorAllocatorType}>> data${pairConstructor};
    std::vector<${firstVectorElementType}${firstVectorAllocatorType}> & ${firstVectorVariable} = data.first;
    std::vector<${secondVectorElementType}${secondVectorAllocatorType}> & ${secondVectorVariable} = data.second;
    ${counterType} ${counterVariable};)";

  return replaceWithMap( dataDeclarationsTemplate,
                         { { "counterType", dataTypes[0] },
                           { "counterVariable", counterVariable },
                           { "firstVectorAllocatorType", firstVectorAllocatorType },
                           { "firstVectorElementType", dataTypes[1] },
                           { "firstVectorVariable", firstVectorVariable },
                           { "pairConstructor", pairConstructor },
                           { "secondVectorAllocatorType", secondVectorAllocatorType },
                           { "secondVectorElementType", dataTypes[2] },
                           { "secondVectorVariable", secondVectorVariable } } );
}

std::string VulkanHppGenerator::generateDataPreparation( CommandData const &                       commandData,
                                                         size_t                                    initialSkipCount,
                                                         std::vector<size_t> const &               returnParams,
                                                         std::map<size_t, VectorParamData> const & vectorParams,
                                                         std::set<size_t> const &                  templatedParams,
                                                         bool                                      singular,
                                                         bool                                      withAllocator,
                                                         bool                                      unique,
                                                         bool                                      chained,
                                                         bool                                      enumerating ) const
{
  auto vectorParamIt = ( 1 < returnParams.size() ) ? vectorParams.find( returnParams[1] ) : vectorParams.end();
  if ( vectorParamIt != vectorParams.end() )
  {
    assert( !unique );

    std::string vectorName = startLowerCase( stripPrefix( commandData.params[vectorParamIt->first].name, "p" ) );

    if ( chained )
    {
      assert( !singular );
      assert( templatedParams.empty() );
      assert( returnParams.size() == 2 );
      assert( vectorParams.find( returnParams[0] ) == vectorParams.end() );
      assert( ( vectorParamIt != vectorParams.end() ) && ( vectorParamIt->second.lenParam == returnParams[0] ) );

      std::string vectorElementType = stripPostfix( commandData.params[vectorParamIt->first].type.compose( "VULKAN_HPP_NAMESPACE" ), " *" );

      if ( enumerating )
      {
        std::string const dataPreparationTemplate =
          R"(VULKAN_HPP_ASSERT( ${counterName} <= ${vectorName}.size() );
      if ( ${counterName} < ${vectorName}.size() )
      {
        structureChains.resize( ${counterName} );
      }
      for ( ${counterType} i = 0; i < ${counterName}; i++ )
      {
        structureChains[i].template get<${vectorElementType}>() = ${vectorName}[i];
      })";

        return replaceWithMap( dataPreparationTemplate,
                               { { "counterName", startLowerCase( stripPrefix( commandData.params[vectorParamIt->second.lenParam].name, "p" ) ) },
                                 { "counterType", commandData.params[vectorParamIt->second.lenParam].type.type },
                                 { "vectorElementType", vectorElementType },
                                 { "vectorName", vectorName } } );
      }
      else
      {
        std::string const dataPreparationTemplate =
          R"(for ( ${counterType} i = 0; i < ${counterName}; i++ )
    {
      structureChains[i].template get<${vectorElementType}>() = ${vectorName}[i];
    })";

        return replaceWithMap( dataPreparationTemplate,
                               { { "counterName", startLowerCase( stripPrefix( commandData.params[vectorParamIt->second.lenParam].name, "p" ) ) },
                                 { "counterType", commandData.params[vectorParamIt->second.lenParam].type.type },
                                 { "vectorElementType", vectorElementType },
                                 { "vectorName", vectorName } } );
      }
    }
    else if ( enumerating )
    {
      assert( !singular );
      assert( ( vectorParams.size() != 2 ) ||
              ( ( vectorParams.begin()->first == returnParams[1] ) && ( vectorParams.begin()->second.lenParam == returnParams[0] ) &&
                ( std::next( vectorParams.begin() )->first == returnParams[2] ) &&
                ( std::next( vectorParams.begin() )->second.lenParam == returnParams[0] ) ) );

      std::string resizes;
      for ( auto const & vp : vectorParams )
      {
        assert( ( std::find( returnParams.begin(), returnParams.end(), vp.first ) != returnParams.end() ) &&
                ( std::find( returnParams.begin(), returnParams.end(), vp.second.lenParam ) != returnParams.end() ) );
        resizes += startLowerCase( stripPrefix( commandData.params[vp.first].name, "p" ) ) + ".resize( " +
                   startLowerCase( stripPrefix( commandData.params[vp.second.lenParam].name, "p" ) ) + " );\n";
      }
      resizes.pop_back();

      std::string const dataPreparationTemplate =
        R"(VULKAN_HPP_ASSERT( ${counterName} <= ${vectorName}.size() );
    if ( ${counterName} < ${vectorName}.size() )
    {
      ${resizes}
    })";

      return replaceWithMap( dataPreparationTemplate,
                             { { "counterName", startLowerCase( stripPrefix( commandData.params[vectorParamIt->second.lenParam].name, "p" ) ) },
                               { "resizes", resizes },
                               { "vectorName", vectorName } } );
    }
  }
  else if ( unique && !singular && ( returnParams.size() == 1 ) && ( vectorParams.find( returnParams[0] ) != vectorParams.end() ) )
  {
    assert( !enumerating );
    std::string              className = initialSkipCount ? stripPrefix( commandData.params[initialSkipCount - 1].type.type, "Vk" ) : "";
    std::string              deleterDefinition;
    std::vector<std::string> lenParts = tokenize( commandData.params[returnParams[0]].len, "->" );
    switch ( lenParts.size() )
    {
      case 1: deleterDefinition = "ObjectDestroy<" + className + ", Dispatch> deleter( *this, allocator, d )"; break;
      case 2:
        {
          auto vpiIt = vectorParams.find( returnParams[0] );
          assert( vpiIt != vectorParams.end() );
          std::string poolType, poolName;
          std::tie( poolType, poolName ) = getPoolTypeAndName( commandData.params[vpiIt->second.lenParam].type.type );
          assert( !poolType.empty() );
          poolType          = stripPrefix( poolType, "Vk" );
          poolName          = startLowerCase( stripPrefix( lenParts[0], "p" ) ) + "." + poolName;
          deleterDefinition = "PoolFree<" + className + ", " + poolType + ", Dispatch> deleter( *this, " + poolName + ", d )";
        }
        break;
    }

    std::string handleType       = stripPrefix( commandData.params[returnParams[0]].type.type, "Vk" );
    std::string uniqueVectorName = "unique" + stripPrefix( commandData.params[returnParams[0]].name, "p" );
    std::string vectorAllocator  = withAllocator ? ( "( " + startLowerCase( handleType ) + "Allocator )" ) : "";
    std::string vectorName       = startLowerCase( stripPrefix( commandData.params[returnParams[0]].name, "p" ) );
    std::string elementName      = stripPluralS( vectorName );
    std::string vectorSize = getVectorSize( commandData.params, vectorParams, returnParams[0], commandData.params[returnParams[0]].type.type, templatedParams );

    std::string const dataPreparationTemplate =
      R"(std::vector<UniqueHandle<VULKAN_HPP_NAMESPACE::${handleType}, Dispatch>, ${handleType}Allocator> ${uniqueVectorName}${vectorAllocator};
    ${uniqueVectorName}.reserve( ${vectorSize} );
    ${deleterDefinition};
    for ( auto const & ${elementName} : ${vectorName} )
    {
      ${uniqueVectorName}.push_back( UniqueHandle<${handleType}, Dispatch>( ${elementName}, deleter ) );
    })";

    return replaceWithMap( dataPreparationTemplate,
                           { { "elementName", elementName },
                             { "deleterDefinition", deleterDefinition },
                             { "handleType", handleType },
                             { "uniqueVectorName", uniqueVectorName },
                             { "vectorAllocator", vectorAllocator },
                             { "vectorName", vectorName },
                             { "vectorSize", vectorSize } } );
  }
  return "";
}

std::string VulkanHppGenerator::generateDataSizeChecks( CommandData const &                       commandData,
                                                        std::vector<size_t> const &               returnParams,
                                                        std::vector<std::string> const &          returnParamTypes,
                                                        std::map<size_t, VectorParamData> const & vectorParams,
                                                        std::set<size_t> const &                  templatedParams,
                                                        bool                                      singular ) const
{
  assert( returnParams.size() == returnParamTypes.size() );
  std::string dataSizeChecks;
  if ( !singular )
  {
    const std::string dataSizeCheckTemplate = R"(    VULKAN_HPP_ASSERT( ${dataSize} % sizeof( ${dataType} ) == 0 );)";
    for ( size_t i = 0; i < returnParams.size(); i++ )
    {
      auto vectorParamIt = vectorParams.find( returnParams[i] );
      if ( ( vectorParamIt != vectorParams.end() ) && ( templatedParams.find( returnParams[i] ) != templatedParams.end() ) &&
           ( std::find( returnParams.begin(), returnParams.end(), vectorParamIt->second.lenParam ) == returnParams.end() ) )
      {
        dataSizeChecks += replaceWithMap( dataSizeCheckTemplate,
                                          { { "dataSize", commandData.params[vectorParamIt->second.lenParam].name }, { "dataType", returnParamTypes[i] } } );
      }
    }
  }

  return dataSizeChecks;
}

std::string VulkanHppGenerator::generateDispatchLoaderDynamic() const
{
  const std::string dispatchLoaderDynamicTemplate = R"(
  using PFN_dummy = void ( * )();

  class DispatchLoaderDynamic : public DispatchLoaderBase
  {
  public:
${commandMembers}

  public:
    DispatchLoaderDynamic() VULKAN_HPP_NOEXCEPT = default;
    DispatchLoaderDynamic( DispatchLoaderDynamic const & rhs ) VULKAN_HPP_NOEXCEPT = default;

#if !defined( VK_NO_PROTOTYPES )
    // This interface is designed to be used for per-device function pointers in combination with a linked vulkan library.
    template <typename DynamicLoader>
    void init(VULKAN_HPP_NAMESPACE::Instance const & instance, VULKAN_HPP_NAMESPACE::Device const & device, DynamicLoader const & dl) VULKAN_HPP_NOEXCEPT
    {
      PFN_vkGetInstanceProcAddr getInstanceProcAddr = dl.template getProcAddress<PFN_vkGetInstanceProcAddr>("vkGetInstanceProcAddr");
      PFN_vkGetDeviceProcAddr getDeviceProcAddr = dl.template getProcAddress<PFN_vkGetDeviceProcAddr>("vkGetDeviceProcAddr");
      init(static_cast<VkInstance>(instance), getInstanceProcAddr, static_cast<VkDevice>(device), device ? getDeviceProcAddr : nullptr);
    }

    // This interface is designed to be used for per-device function pointers in combination with a linked vulkan library.
    template <typename DynamicLoader
#if VULKAN_HPP_ENABLE_DYNAMIC_LOADER_TOOL
      = VULKAN_HPP_NAMESPACE::DynamicLoader
#endif
    >
    void init(VULKAN_HPP_NAMESPACE::Instance const & instance, VULKAN_HPP_NAMESPACE::Device const & device) VULKAN_HPP_NOEXCEPT
    {
      static DynamicLoader dl;
      init(instance, device, dl);
    }
#endif // !defined( VK_NO_PROTOTYPES )

    DispatchLoaderDynamic(PFN_vkGetInstanceProcAddr getInstanceProcAddr) VULKAN_HPP_NOEXCEPT
    {
      init(getInstanceProcAddr);
    }

    void init( PFN_vkGetInstanceProcAddr getInstanceProcAddr ) VULKAN_HPP_NOEXCEPT
    {
      VULKAN_HPP_ASSERT(getInstanceProcAddr);

      vkGetInstanceProcAddr = getInstanceProcAddr;

${initialCommandAssignments}
    }

    // This interface does not require a linked vulkan library.
    DispatchLoaderDynamic( VkInstance                instance,
                           PFN_vkGetInstanceProcAddr getInstanceProcAddr,
                           VkDevice                  device            = {},
                           PFN_vkGetDeviceProcAddr   getDeviceProcAddr = nullptr ) VULKAN_HPP_NOEXCEPT
    {
      init( instance, getInstanceProcAddr, device, getDeviceProcAddr );
    }

    // This interface does not require a linked vulkan library.
    void init( VkInstance                instance,
               PFN_vkGetInstanceProcAddr getInstanceProcAddr,
               VkDevice                  device              = {},
               PFN_vkGetDeviceProcAddr /*getDeviceProcAddr*/ = nullptr ) VULKAN_HPP_NOEXCEPT
    {
      VULKAN_HPP_ASSERT(instance && getInstanceProcAddr);
      vkGetInstanceProcAddr = getInstanceProcAddr;
      init( VULKAN_HPP_NAMESPACE::Instance(instance) );
      if (device) {
        init( VULKAN_HPP_NAMESPACE::Device(device) );
      }
    }

    void init( VULKAN_HPP_NAMESPACE::Instance instanceCpp ) VULKAN_HPP_NOEXCEPT
    {
      VkInstance instance = static_cast<VkInstance>(instanceCpp);

${instanceCommandAssignments}
    }

    void init( VULKAN_HPP_NAMESPACE::Device deviceCpp ) VULKAN_HPP_NOEXCEPT
    {
      VkDevice device = static_cast<VkDevice>(deviceCpp);

${deviceCommandAssignments}
    }
  };)";

  std::string           commandMembers, deviceCommandAssignments, initialCommandAssignments, instanceCommandAssignments;
  std::set<std::string> listedCommands;  // some commands are listed with more than one extension!
  for ( auto const & feature : m_features )
  {
    appendDispatchLoaderDynamicCommands( feature.second.requireData,
                                         listedCommands,
                                         feature.first,
                                         commandMembers,
                                         initialCommandAssignments,
                                         instanceCommandAssignments,
                                         deviceCommandAssignments );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    appendDispatchLoaderDynamicCommands( extIt.second->second.requireData,
                                         listedCommands,
                                         extIt.second->first,
                                         commandMembers,
                                         initialCommandAssignments,
                                         instanceCommandAssignments,
                                         deviceCommandAssignments );
  }

  return replaceWithMap( dispatchLoaderDynamicTemplate,
                         { { "commandMembers", commandMembers },
                           { "deviceCommandAssignments", deviceCommandAssignments },
                           { "initialCommandAssignments", initialCommandAssignments },
                           { "instanceCommandAssignments", instanceCommandAssignments } } );
}

std::string VulkanHppGenerator::generateDispatchLoaderStatic() const
{
  const std::string dispatchLoaderStaticTemplate = R"(
#if !defined( VK_NO_PROTOTYPES )
  class DispatchLoaderStatic : public DispatchLoaderBase
  {
  public:
${commands}
  };
#endif
)";

  std::string           commands;
  std::set<std::string> listedCommands;
  for ( auto const & feature : m_features )
  {
    commands += generateDispatchLoaderStaticCommands( feature.second.requireData, listedCommands, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    commands += generateDispatchLoaderStaticCommands( extIt.second->second.requireData, listedCommands, extIt.second->first );
  }

  return replaceWithMap( dispatchLoaderStaticTemplate, { { "commands", commands } } );
}

std::string VulkanHppGenerator::generateDestroyCommand( std::string const & name, CommandData const & commandData ) const
{
  // special handling for destroy functions, filter out alias functions
  std::string commandName = generateCommandName( name, commandData.params, 1, m_tags, false, false );
  if ( commandData.alias.empty() && ( ( ( name.substr( 2, 7 ) == "Destroy" ) && ( commandName != "destroy" ) ) || ( name.substr( 2, 4 ) == "Free" ) ||
                                      ( name == "vkReleasePerformanceConfigurationINTEL" ) ) )
  {
    assert( 1 < commandData.params.size() );
    // make sure, the object to destroy/free/release is not optional in the shortened version!
    CommandData localCommandData        = commandData;
    localCommandData.params[1].optional = false;

    std::string destroyCommandString = generateCommand( name, localCommandData, 1, false );
    std::string shortenedName;
    if ( name.substr( 2, 7 ) == "Destroy" )
    {
      shortenedName = "destroy";
    }
    else if ( name.substr( 2, 4 ) == "Free" )
    {
      // enclose "free" in parenthesis to prevent interference with MSVC debug free
      shortenedName = "( free )";
    }
    else
    {
      assert( name == "vkReleasePerformanceConfigurationINTEL" );
      shortenedName = "release";
    }
    size_t pos = destroyCommandString.find( commandName );
    while ( pos != std::string::npos )
    {
      destroyCommandString.replace( pos, commandName.length(), shortenedName );
      pos = destroyCommandString.find( commandName, pos );
    }
    // we need to remove the default argument for the first argument, to prevent ambiguities!
    assert( 1 < localCommandData.params.size() );
    pos = destroyCommandString.find( localCommandData.params[1].name );  // skip the standard version of the function
    assert( pos != std::string::npos );
    pos = destroyCommandString.find( localCommandData.params[1].name,
                                     pos + 1 );  // get the argument to destroy in the advanced version
    assert( pos != std::string::npos );
    pos = destroyCommandString.find( " VULKAN_HPP_DEFAULT_ARGUMENT_ASSIGNMENT", pos );
    if ( pos != std::string::npos )
    {
      destroyCommandString.erase( pos, strlen( " VULKAN_HPP_DEFAULT_ARGUMENT_ASSIGNMENT" ) );
    }
    return "\n" + destroyCommandString;
  }
  return "";
}

std::string VulkanHppGenerator::generateDispatchLoaderDynamicCommandAssignment( std::string const & commandName,
                                                                                CommandData const & commandData,
                                                                                std::string const & firstArg ) const
{
  if ( commandName == "vkGetInstanceProcAddr" )
  {
    // Don't overwite vkGetInstanceProcAddr with NULL.
    return "";
  }
  std::string str = "      " + commandName + " = PFN_" + commandName + "( vkGet" + ( ( firstArg == "device" ) ? "Device" : "Instance" ) + "ProcAddr( " +
                    firstArg + ", \"" + commandName + "\" ) );\n";
  // if this is an alias'ed function, use it as a fallback for the original one
  if ( !commandData.alias.empty() )
  {
    str += "      if ( !" + commandData.alias + " ) " + commandData.alias + " = " + commandName + ";\n";
  }
  return str;
}

std::string VulkanHppGenerator::generateDispatchLoaderStaticCommands( std::vector<RequireData> const & requireData,
                                                                      std::set<std::string> &          listedCommands,
                                                                      std::string const &              title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & command : require.commands )
    {
      // some commands are listed for multiple extensions !
      if ( listedCommands.insert( command ).second )
      {
        auto commandIt = m_commands.find( command );
        assert( commandIt != m_commands.end() );

        str += "\n";
        std::string parameterList, parameters;
        assert( !commandIt->second.params.empty() );
        for ( auto param : commandIt->second.params )
        {
          parameterList += param.type.compose( "" ) + " " + param.name + generateCArraySizes( param.arraySizes ) + ", ";
          parameters += param.name + ", ";
        }
        assert( parameterList.ends_with( ", " ) && parameters.ends_with( ", " ) );
        parameterList.resize( parameterList.size() - 2 );
        parameters.resize( parameters.size() - 2 );

        const std::string commandTemplate = R"(
    ${returnType} ${commandName}( ${parameterList} ) const VULKAN_HPP_NOEXCEPT
    {
      return ::${commandName}( ${parameters} );
    }
)";

        str += replaceWithMap( commandTemplate,
                               { { "commandName", commandIt->first },
                                 { "parameterList", parameterList },
                                 { "parameters", parameters },
                                 { "returnType", commandIt->second.returnType } } );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateEnum( std::pair<std::string, EnumData> const & enumData ) const
{
  std::string bitmask;
  if ( enumData.second.isBitmask )
  {
    auto bitmaskIt =
      std::find_if( m_bitmasks.begin(), m_bitmasks.end(), [&enumData]( auto const & bitmask ) { return bitmask.second.requirements == enumData.first; } );
    assert( bitmaskIt != m_bitmasks.end() );
    bitmask = " : " + bitmaskIt->first;
  }

  std::string                        enumValues, previousEnter, previousLeave;
  std::map<std::string, std::string> valueToNameMap;
  for ( auto const & value : enumData.second.values )
  {
    auto [enter, leave] = generateProtection( value.extension, value.protect );
    if ( previousEnter != enter )
    {
      enumValues += previousLeave + enter;
    }
    std::string valueName = generateEnumValueName( enumData.first, value.name, enumData.second.isBitmask, m_tags );
    enumValues += "    " + valueName + " = " + value.name + ",\n";
    assert( valueToNameMap.find( valueName ) == valueToNameMap.end() );
    valueToNameMap[valueName] = value.name;

    previousEnter = enter;
    previousLeave = leave;
  }
  enumValues += previousLeave;

  for ( auto const & alias : enumData.second.aliases )
  {
    std::string aliasName =
      generateEnumValueName( enumData.second.alias.empty() ? enumData.first : enumData.second.alias, alias.first, enumData.second.isBitmask, m_tags );
    // make sure to only list alias values that differ from all previous values
    auto valueToNameIt = valueToNameMap.find( aliasName );
    if ( valueToNameIt == valueToNameMap.end() )
    {
#if !defined( NDEBUG )
      auto enumIt = std::find_if(
        enumData.second.values.begin(), enumData.second.values.end(), [&alias]( EnumValueData const & evd ) { return alias.second.name == evd.name; } );
      if ( enumIt == enumData.second.values.end() )
      {
        auto aliasIt = enumData.second.aliases.find( alias.second.name );
        assert( aliasIt != enumData.second.aliases.end() );
        auto nextAliasIt = enumData.second.aliases.find( aliasIt->second.name );
        while ( nextAliasIt != enumData.second.aliases.end() )
        {
          aliasIt     = nextAliasIt;
          nextAliasIt = enumData.second.aliases.find( aliasIt->second.name );
        }
        enumIt = std::find_if(
          enumData.second.values.begin(), enumData.second.values.end(), [&aliasIt]( EnumValueData const & evd ) { return aliasIt->second.name == evd.name; } );
      }
      assert( enumIt != enumData.second.values.end() );
      assert( enumIt->extension.empty() || generateProtection( enumIt->extension, enumIt->protect ).first.empty() );
#endif
      enumValues += "    " + aliasName + " = " + alias.first + ",\n";

      // map the aliasName to the name of the base
      std::string baseName = findBaseName( alias.second.name, enumData.second.aliases );
      assert( std::find_if( enumData.second.values.begin(),
                            enumData.second.values.end(),
                            [&baseName]( EnumValueData const & evd ) { return evd.name == baseName; } ) != enumData.second.values.end() );
      valueToNameMap[aliasName] = baseName;
    }
#if !defined( NDEBUG )
    else
    {
      // verify, that the identical value represents the identical name
      std::string baseName = findBaseName( alias.second.name, enumData.second.aliases );
      assert( std::find_if( enumData.second.values.begin(),
                            enumData.second.values.end(),
                            [&baseName]( EnumValueData const & evd ) { return evd.name == baseName; } ) != enumData.second.values.end() );
      assert( baseName == valueToNameIt->second );
    }
#endif
  }
  if ( !enumValues.empty() )
  {
    size_t pos = enumValues.rfind( ',' );
    assert( pos != std::string::npos );
    enumValues.erase( pos, 1 );
    enumValues = "\n" + enumValues + "  ";
  }

  std::string enumUsing;
  if ( !enumData.second.alias.empty() )
  {
    enumUsing += "  using " + stripPrefix( enumData.second.alias, "Vk" ) + " = " + stripPrefix( enumData.first, "Vk" ) + ";\n";
  }

  const std::string enumTemplate = R"(  enum class ${enumName}${bitmask}
  {${enumValues}};
${enumUsing})";

  return replaceWithMap(
    enumTemplate, { { "bitmask", bitmask }, { "enumName", stripPrefix( enumData.first, "Vk" ) }, { "enumUsing", enumUsing }, { "enumValues", enumValues } } );
}

std::string VulkanHppGenerator::generateEnums() const
{
  const std::string enumsTemplate = R"(
  //=============
  //=== ENUMs ===
  //=============

${enums}
)";

  std::string           enums;
  std::set<std::string> listedEnums;
  for ( auto const & feature : m_features )
  {
    enums += generateEnums( feature.second.requireData, listedEnums, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    enums += generateEnums( extIt.second->second.requireData, listedEnums, extIt.second->first );
  }

  return replaceWithMap( enumsTemplate, { { "enums", enums } } );
}

std::string
  VulkanHppGenerator::generateEnums( std::vector<RequireData> const & requireData, std::set<std::string> & listedEnums, std::string const & title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto enumIt = m_enums.find( type );
      if ( ( enumIt != m_enums.end() ) && ( listedEnums.find( type ) == listedEnums.end() ) )
      {
        listedEnums.insert( type );

        str += "\n";
        str += generateEnum( *enumIt );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateEnumsToString() const
{
  // start with toHexString, which is used in all the to_string functions here!
  const std::string enumsToStringTemplate = R"(
  //=======================
  //=== ENUMs to_string ===
  //=======================

  VULKAN_HPP_INLINE std::string toHexString( uint32_t value )
  {
#if __cpp_lib_format
    return std::format( "{:x}", value );
#else
    std::stringstream stream;
    stream << std::hex << value;
    return stream.str();
#endif
  }

${enumsToString}
)";

  std::string           enumsToString;
  std::set<std::string> listedEnums;
  for ( auto const & feature : m_features )
  {
    enumsToString += generateEnumsToString( feature.second.requireData, listedEnums, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    enumsToString += generateEnumsToString( extIt.second->second.requireData, listedEnums, extIt.second->first );
  }

  return replaceWithMap( enumsToStringTemplate, { { "enumsToString", enumsToString } } );
}

std::string VulkanHppGenerator::generateEnumsToString( std::vector<RequireData> const & requireData,
                                                       std::set<std::string> &          listedEnums,
                                                       std::string const &              title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto enumIt = m_enums.find( type );
      if ( ( enumIt != m_enums.end() ) && ( listedEnums.find( type ) == listedEnums.end() ) )
      {
        listedEnums.insert( type );

        str += "\n";
        str += generateEnumToString( *enumIt );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateEnumInitializer( TypeInfo const &                   type,
                                                         std::vector<std::string> const &   arraySizes,
                                                         std::vector<EnumValueData> const & values,
                                                         bool                               bitmask ) const
{
  // enum arguments might need special initialization
  assert( type.prefix.empty() && !values.empty() );
  std::string valueName = generateEnumValueName( type.type, values.front().name, bitmask, m_tags );
  std::string value     = generateNamespacedType( type.type ) + "::" + valueName;
  std::string str;
  if ( arraySizes.empty() )
  {
    str += value;
  }
  else
  {
    assert( arraySizes.size() == 1 );
    auto constIt = m_constants.find( arraySizes[0] );
    int  count   = std::stoi( ( constIt == m_constants.end() ) ? arraySizes[0] : constIt->second );
    assert( 1 < count );
    str += "{ { " + value;
    for ( int i = 1; i < count; i++ )
    {
      str += ", " + value;
    }
    str += " } }";
  }
  return str;
}

std::string VulkanHppGenerator::generateEnumToString( std::pair<std::string, EnumData> const & enumData ) const
{
  std::string enumName = stripPrefix( enumData.first, "Vk" );
  std::string functionBody;
  if ( enumData.second.values.empty() )
  {
    functionBody = R"x(    return "(void)";)x";
  }
  else
  {
    std::string cases, previousEnter, previousLeave;
    for ( auto const & value : enumData.second.values )
    {
      auto [enter, leave] = generateProtection( value.extension, value.protect );
      if ( previousEnter != enter )
      {
        cases += previousLeave + enter;
      }

      const std::string caseTemplate = R"(      case ${enumName}::e${valueName} : return "${valueName}";
)";
      cases += replaceWithMap(
        caseTemplate,
        { { "enumName", enumName }, { "valueName", generateEnumValueName( enumData.first, value.name, enumData.second.isBitmask, m_tags ).substr( 1 ) } } );

      previousEnter = enter;
      previousLeave = leave;
    }
    cases += previousLeave;

    const std::string functionBodyTemplate =
      R"x(    switch ( value )
    {
${cases}      default: return "invalid ( " + VULKAN_HPP_NAMESPACE::toHexString( static_cast<uint32_t>( value ) ) + " )";
    }
)x";

    functionBody = replaceWithMap( functionBodyTemplate, { { "cases", cases } } );
  }

  const std::string enumToStringTemplate = R"(
  VULKAN_HPP_INLINE std::string to_string( ${enumName}${argument} )
  {
${functionBody}
  }
)";

  return replaceWithMap( enumToStringTemplate,
                         { { "argument", enumData.second.values.empty() ? "" : " value" }, { "enumName", enumName }, { "functionBody", functionBody } } );
}

std::string VulkanHppGenerator::generateFailureCheck( std::vector<std::string> const & successCodes ) const
{
  assert( !successCodes.empty() );
  std::string failureCheck = "result != " + generateSuccessCode( successCodes[0], m_tags );
  if ( 1 < successCodes.size() )
  {
    failureCheck = "( " + failureCheck + " )";
    for ( size_t i = 1; i < successCodes.size(); ++i )
    {
      failureCheck += "&& ( result != " + generateSuccessCode( successCodes[i], m_tags ) + " )";
    }
  }
  return failureCheck;
}

std::string VulkanHppGenerator::generateFormatTraits() const
{
  if ( m_formats.empty() )
  {
    return "";
  }

  const std::string formatTraitsTemplate = R"(
  //=====================
  //=== Format Traits ===
  //=====================

  // The texel block size in bytes.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t blockSize( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${blockSizeCases}
      default : VULKAN_HPP_ASSERT( false ); return 0;
    }
  }

  // The number of texels in a texel block.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t texelsPerBlock( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${texelsPerBlockCases}
      default: VULKAN_HPP_ASSERT( false ); return 0;
    }
  }

  // The three-dimensional extent of a texel block.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 std::array<uint8_t, 3> blockExtent( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${blockExtentCases}
      default: return {{1, 1, 1 }};
    }
  }

  // A textual description of the compression scheme, or an empty string if it is not compressed
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 char const * compressionScheme( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${compressionSchemeCases}
      default: return "";
    }
  }

  // True, if this format is a compressed one.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 bool isCompressed( VULKAN_HPP_NAMESPACE::Format format )
  {
    return ( *VULKAN_HPP_NAMESPACE::compressionScheme( format ) != 0 );
  }

  // The number of bits into which the format is packed. A single image element in this format
  // can be stored in the same space as a scalar type of this bit width.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t packed( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${packedCases}
      default: return 0;
    }
  }

  // True, if the components of this format are compressed, otherwise false.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 bool componentsAreCompressed( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${componentsAreCompressedCases}
        return true;
      default: return false;
    }
  }

  // The number of bits in this component, if not compressed, otherwise 0.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t componentBits( VULKAN_HPP_NAMESPACE::Format format, uint8_t component )
  {
    switch( format )
    {
${componentBitsCases}
      default: return 0;
    }
  }

  // The number of components of this format.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t componentCount( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${componentCountCases}
      default: return 0;
    }
  }

  // The name of the component
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 char const * componentName( VULKAN_HPP_NAMESPACE::Format format, uint8_t component )
  {
    switch( format )
    {
${componentNameCases}
      default: return "";
    }
  }

  // The numeric format of the component
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 char const * componentNumericFormat( VULKAN_HPP_NAMESPACE::Format format, uint8_t component )
  {
    switch( format )
    {
${componentNumericFormatCases}
      default: return "";
    }
  }

  // The plane this component lies in.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t componentPlaneIndex( VULKAN_HPP_NAMESPACE::Format format, uint8_t component )
  {
    switch( format )
    {
${componentPlaneIndexCases}
      default: return 0;
    }
  }

  // The number of image planes of this format.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t planeCount( VULKAN_HPP_NAMESPACE::Format format )
  {
    switch( format )
    {
${planeCountCases}
      default: return 1;
    }
  }

  // The single-plane format that this plane is compatible with.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 VULKAN_HPP_NAMESPACE::Format planeCompatibleFormat( VULKAN_HPP_NAMESPACE::Format format, uint8_t plane )
  {
    switch( format )
    {
${planeCompatibleCases}
      default: VULKAN_HPP_ASSERT( plane == 0 ); return format;
    }
  }

  // The relative height of this plane. A value of k means that this plane is 1/k the height of the overall format.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t planeHeightDivisor( VULKAN_HPP_NAMESPACE::Format format, uint8_t plane )
  {
    switch( format )
    {
${planeHeightDivisorCases}
      default: VULKAN_HPP_ASSERT( plane == 0 ); return 1;
    }
  }

  // The relative width of this plane. A value of k means that this plane is 1/k the width of the overall format.
  VULKAN_HPP_INLINE VULKAN_HPP_CONSTEXPR_14 uint8_t planeWidthDivisor( VULKAN_HPP_NAMESPACE::Format format, uint8_t plane )
  {
    switch( format )
    {
${planeWidthDivisorCases}
      default: VULKAN_HPP_ASSERT( plane == 0 ); return 1;
    }
  }
)";

  auto formatIt = m_enums.find( "VkFormat" );
  assert( formatIt != m_enums.end() );
  assert( formatIt->second.values.front().name == "VK_FORMAT_UNDEFINED" );

  std::string blockSizeCases, texelsPerBlockCases, blockExtentCases, compressionSchemeCases, packedCases, componentsAreCompressedCases, componentCountCases,
    componentBitsCases, componentNameCases, componentNumericFormatCases, componentPlaneIndexCases, planeCountCases, planeCompatibleCases,
    planeHeightDivisorCases, planeWidthDivisorCases;
  for ( auto formatValuesIt = std::next( formatIt->second.values.begin() ); formatValuesIt != formatIt->second.values.end(); ++formatValuesIt )
  {
    auto traitIt = m_formats.find( formatValuesIt->name );
    assert( traitIt != m_formats.end() );
    std::string caseString = "      case VULKAN_HPP_NAMESPACE::Format::" + generateEnumValueName( "VkFormat", traitIt->first, false, m_tags ) + ":";
    blockSizeCases += caseString + " return " + traitIt->second.blockSize + ";\n";
    texelsPerBlockCases += caseString + " return " + traitIt->second.texelsPerBlock + ";\n";
    if ( !traitIt->second.blockExtent.empty() )
    {
      std::vector<std::string> blockExtent = tokenize( traitIt->second.blockExtent, "," );
      assert( blockExtent.size() == 3 );
      blockExtentCases += caseString + " return {{ " + blockExtent[0] + ", " + blockExtent[1] + ", " + blockExtent[2] + " }};\n";
    }
    if ( !traitIt->second.compressed.empty() )
    {
      compressionSchemeCases += caseString + " return \"" + traitIt->second.compressed + "\";\n";
    }
    if ( !traitIt->second.packed.empty() )
    {
      packedCases += caseString + " return " + traitIt->second.packed + ";\n";
    }
    componentCountCases += caseString + " return " + std::to_string( traitIt->second.components.size() ) + ";\n";
    if ( traitIt->second.components.front().bits == "compressed" )
    {
      componentsAreCompressedCases += caseString + "\n";
    }
    else
    {
      const std::string componentBitsCaseTemplate = R"(${caseString}
        switch( component )
        {
${componentCases}
          default: VULKAN_HPP_ASSERT( false ); return 0;
        }
)";

      std::string componentCases;
      for ( size_t i = 0; i < traitIt->second.components.size(); ++i )
      {
        componentCases += "          case " + std::to_string( i ) + ": return " + traitIt->second.components[i].bits + ";\n";
      }
      componentCases.pop_back();
      componentBitsCases += replaceWithMap( componentBitsCaseTemplate, { { "caseString", caseString }, { "componentCases", componentCases } } );
    }

    {
      const std::string componentNameCaseTemplate = R"(${caseString}
        switch( component )
        {
${componentCases}
          default: VULKAN_HPP_ASSERT( false ); return "";
        }
)";

      std::string componentCases;
      for ( size_t i = 0; i < traitIt->second.components.size(); ++i )
      {
        componentCases += "          case " + std::to_string( i ) + ": return \"" + traitIt->second.components[i].name + "\";\n";
      }
      componentCases.pop_back();
      componentNameCases += replaceWithMap( componentNameCaseTemplate, { { "caseString", caseString }, { "componentCases", componentCases } } );
    }

    {
      const std::string componentNumericFormatCaseTemplate = R"(${caseString}
        switch( component )
        {
${componentCases}
          default: VULKAN_HPP_ASSERT( false ); return "";
        }
)";

      std::string componentCases;
      for ( size_t i = 0; i < traitIt->second.components.size(); ++i )
      {
        componentCases += "          case " + std::to_string( i ) + ": return \"" + traitIt->second.components[i].numericFormat + "\";\n";
      }
      componentCases.pop_back();
      componentNumericFormatCases +=
        replaceWithMap( componentNumericFormatCaseTemplate, { { "caseString", caseString }, { "componentCases", componentCases } } );
    }

    if ( !traitIt->second.components.front().planeIndex.empty() )
    {
      const std::string componentPlaneIndexCaseTemplate = R"(${caseString}
        switch( component )
        {
${componentCases}
          default: VULKAN_HPP_ASSERT( false ); return 0;
        }
)";

      std::string componentCases;
      for ( size_t i = 0; i < traitIt->second.components.size(); ++i )
      {
        componentCases += "          case " + std::to_string( i ) + ": return " + traitIt->second.components[i].planeIndex + ";\n";
      }
      componentCases.pop_back();
      componentPlaneIndexCases += replaceWithMap( componentPlaneIndexCaseTemplate, { { "caseString", caseString }, { "componentCases", componentCases } } );
    }
    if ( !traitIt->second.planes.empty() )
    {
      planeCountCases += caseString + " return " + std::to_string( traitIt->second.planes.size() ) + ";\n";

      const std::string planeCompatibleCaseTemplate = R"(${caseString}
        switch( plane )
        {
${compatibleCases}
          default: VULKAN_HPP_ASSERT( false ); return VULKAN_HPP_NAMESPACE::Format::eUndefined;
        }
)";

      const std::string planeHeightDivisorCaseTemplate = R"(${caseString}
        switch( plane )
        {
${heightDivisorCases}
          default: VULKAN_HPP_ASSERT( false ); return 1;
        }
)";

      const std::string planeWidthDivisorCaseTemplate = R"(${caseString}
        switch( plane )
        {
${widthDivisorCases}
          default: VULKAN_HPP_ASSERT( false ); return 1;
        }
)";

      std::string compatibleCases, heightDivisorCases, widthDivisorCases;
      for ( size_t i = 0; i < traitIt->second.planes.size(); ++i )
      {
        compatibleCases += "          case " + std::to_string( i ) + ": return VULKAN_HPP_NAMESPACE::Format::" +
                           generateEnumValueName( "VkFormat", traitIt->second.planes[i].compatible, false, m_tags ) + ";\n";
        heightDivisorCases += "          case " + std::to_string( i ) + ": return " + traitIt->second.planes[i].heightDivisor + ";\n";
        widthDivisorCases += "          case " + std::to_string( i ) + ": return " + traitIt->second.planes[i].widthDivisor + ";\n";
      }
      compatibleCases.pop_back();
      heightDivisorCases.pop_back();
      widthDivisorCases.pop_back();
      planeCompatibleCases += replaceWithMap( planeCompatibleCaseTemplate, { { "caseString", caseString }, { "compatibleCases", compatibleCases } } );
      planeHeightDivisorCases +=
        replaceWithMap( planeHeightDivisorCaseTemplate, { { "caseString", caseString }, { "heightDivisorCases", heightDivisorCases } } );
      planeWidthDivisorCases += replaceWithMap( planeWidthDivisorCaseTemplate, { { "caseString", caseString }, { "widthDivisorCases", widthDivisorCases } } );
    }
  }

  return replaceWithMap( formatTraitsTemplate,
                         { { "blockExtentCases", blockExtentCases },
                           { "blockSizeCases", blockSizeCases },
                           { "componentBitsCases", componentBitsCases },
                           { "componentCountCases", componentCountCases },
                           { "componentNameCases", componentNameCases },
                           { "componentNumericFormatCases", componentNumericFormatCases },
                           { "componentPlaneIndexCases", componentPlaneIndexCases },
                           { "componentsAreCompressedCases", componentsAreCompressedCases },
                           { "compressionSchemeCases", compressionSchemeCases },
                           { "packedCases", packedCases },
                           { "planeCompatibleCases", planeCompatibleCases },
                           { "planeCountCases", planeCountCases },
                           { "planeHeightDivisorCases", planeHeightDivisorCases },
                           { "planeWidthDivisorCases", planeWidthDivisorCases },
                           { "texelsPerBlockCases", texelsPerBlockCases } } );
}

std::string VulkanHppGenerator::generateFunctionPointerCheck( std::string const & function, std::string const & referencedIn ) const
{
  std::string functionPointerCheck;
  if ( m_extensions.find( referencedIn ) != m_extensions.end() )
  {
    std::string message  = "Function <" + function + "> needs extension <" + referencedIn + "> enabled!";
    functionPointerCheck = "VULKAN_HPP_ASSERT( getDispatcher()->" + function + " && \"" + message + "\" );";
  }
  return functionPointerCheck;
}

std::string VulkanHppGenerator::generateHandle( std::pair<std::string, HandleData> const & handleData, std::set<std::string> & listedHandles ) const
{
  assert( listedHandles.find( handleData.first ) == listedHandles.end() );

  // first check for any handle that needs to be listed before this one
  std::string str = generateHandleDependencies( handleData, listedHandles );

  // list the commands of this handle
  if ( handleData.first.empty() )
  {
    // the free functions, not bound to any handle
    str += generateHandleEmpty( handleData.second );
  }
  else
  {
    // append any forward declaration of Deleters used by this handle
    if ( !handleData.second.childrenHandles.empty() )
    {
      str += generateUniqueTypes( handleData.first, handleData.second.childrenHandles );
    }
    else if ( handleData.first == "VkPhysicalDevice" )
    {
      // special handling for class Device, as it's created from PhysicalDevice, but destroys itself
      str += generateUniqueTypes( "", { "VkDevice" } );
    }

    // list all the commands that are mapped to members of this class
    std::string commands = generateHandleCommandDeclarations( handleData.second.commands );

    // create CPPType template specialization and the debugReportObjectType
    std::string valueName = handleData.second.objTypeEnum;
    valueName             = valueName.replace( 3, 0, "DEBUG_REPORT_" ) + "_EXT";
    auto enumIt           = m_enums.find( "VkDebugReportObjectTypeEXT" );
    assert( enumIt != m_enums.end() );
    auto valueIt =
      std::find_if( enumIt->second.values.begin(), enumIt->second.values.end(), [&valueName]( EnumValueData const & evd ) { return valueName == evd.name; } );

    std::string className = stripPrefix( handleData.first, "Vk" );
    std::string cppType, debugReportObjectType;
    if ( valueIt == enumIt->second.values.end() )
    {
      debugReportObjectType = "eUnknown";
    }
    else
    {
      static const std::string cppTypeFromDebugReportObjectTypeEXTTemplate = R"(
  template <>
  struct CppType<VULKAN_HPP_NAMESPACE::DebugReportObjectTypeEXT, VULKAN_HPP_NAMESPACE::DebugReportObjectTypeEXT::e${className}>
  {
    using Type = VULKAN_HPP_NAMESPACE::${className};
  };
)";
      cppType               = replaceWithMap( cppTypeFromDebugReportObjectTypeEXTTemplate, { { "className", className } } );
      debugReportObjectType = generateEnumValueName( enumIt->first, valueIt->name, false, m_tags );
    }

    auto [enter, leave] = generateProtection( handleData.first, !handleData.second.alias.empty() );

    assert( !handleData.second.objTypeEnum.empty() );
    enumIt = m_enums.find( "VkObjectType" );
    assert( enumIt != m_enums.end() );
    valueIt = std::find_if( enumIt->second.values.begin(),
                            enumIt->second.values.end(),
                            [&handleData]( EnumValueData const & evd ) { return evd.name == handleData.second.objTypeEnum; } );
    assert( valueIt != enumIt->second.values.end() );
    std::string usingAlias;
    if ( !handleData.second.alias.empty() )
    {
      usingAlias += "  using " + stripPrefix( handleData.second.alias, "Vk" ) + " = " + stripPrefix( handleData.first, "Vk" ) + ";\n";
    }

    const std::string typesafeExplicitKeyword          = handleData.second.isDispatchable ? "" : "VULKAN_HPP_TYPESAFE_EXPLICIT ";
    const std::string typesafeConversionConditional    = handleData.second.isDispatchable ? "" : "#if defined(VULKAN_HPP_TYPESAFE_CONVERSION)\n";
    const std::string typesafeConversionConditionalEnd = handleData.second.isDispatchable ? "" : "#endif\n";

    static const std::string templateString = R"(
${enter}  class ${className}
  {
  public:
    using CType = Vk${className};
    using NativeType = Vk${className};

    static VULKAN_HPP_CONST_OR_CONSTEXPR VULKAN_HPP_NAMESPACE::ObjectType objectType = VULKAN_HPP_NAMESPACE::ObjectType::${objTypeEnum};
    static VULKAN_HPP_CONST_OR_CONSTEXPR VULKAN_HPP_NAMESPACE::DebugReportObjectTypeEXT debugReportObjectType = VULKAN_HPP_NAMESPACE::DebugReportObjectTypeEXT::${debugReportObjectType};

  public:
    VULKAN_HPP_CONSTEXPR ${className}() = default;
    VULKAN_HPP_CONSTEXPR ${className}( std::nullptr_t ) VULKAN_HPP_NOEXCEPT
    {}
    ${typesafeExplicitKeyword}${className}( Vk${className} ${memberName} ) VULKAN_HPP_NOEXCEPT
      : m_${memberName}( ${memberName} )
    {}

${typesafeConversionConditional}    ${className} & operator=(Vk${className} ${memberName}) VULKAN_HPP_NOEXCEPT
    {
      m_${memberName} = ${memberName};
      return *this;
    }
${typesafeConversionConditionalEnd}
    ${className} & operator=( std::nullptr_t ) VULKAN_HPP_NOEXCEPT
    {
      m_${memberName} = {};
      return *this;
    }

#if defined(VULKAN_HPP_HAS_SPACESHIP_OPERATOR)
    auto operator<=>( ${className} const & ) const = default;
#else
    bool operator==( ${className} const & rhs ) const VULKAN_HPP_NOEXCEPT
    {
      return m_${memberName} == rhs.m_${memberName};
    }

    bool operator!=(${className} const & rhs ) const VULKAN_HPP_NOEXCEPT
    {
      return m_${memberName} != rhs.m_${memberName};
    }

    bool operator<(${className} const & rhs ) const VULKAN_HPP_NOEXCEPT
    {
      return m_${memberName} < rhs.m_${memberName};
    }
#endif
${commands}
    ${typesafeExplicitKeyword}operator Vk${className}() const VULKAN_HPP_NOEXCEPT
    {
      return m_${memberName};
    }

    explicit operator bool() const VULKAN_HPP_NOEXCEPT
    {
      return m_${memberName} != VK_NULL_HANDLE;
    }

    bool operator!() const VULKAN_HPP_NOEXCEPT
    {
      return m_${memberName} == VK_NULL_HANDLE;
    }

  private:
    Vk${className} m_${memberName} = {};
  };

  template <>
  struct CppType<VULKAN_HPP_NAMESPACE::ObjectType, VULKAN_HPP_NAMESPACE::ObjectType::${objTypeEnum}>
  {
    using Type = VULKAN_HPP_NAMESPACE::${className};
  };

${CppType}

  template <>
  struct isVulkanHandleType<VULKAN_HPP_NAMESPACE::${className}>
  {
    static VULKAN_HPP_CONST_OR_CONSTEXPR bool value = true;
  };
${usingAlias}${leave})";

    str += replaceWithMap( templateString,
                           { { "className", className },
                             { "commands", commands },
                             { "CppType", cppType },
                             { "debugReportObjectType", debugReportObjectType },
                             { "enter", enter },
                             { "leave", leave },
                             { "memberName", startLowerCase( stripPrefix( handleData.first, "Vk" ) ) },
                             { "objTypeEnum", generateEnumValueName( enumIt->first, valueIt->name, false, m_tags ) },
                             { "usingAlias", usingAlias },
                             { "typesafeExplicitKeyword", typesafeExplicitKeyword },
                             { "typesafeConversionConditional", typesafeConversionConditional },
                             { "typesafeConversionConditionalEnd", typesafeConversionConditionalEnd } } );
  }

  listedHandles.insert( handleData.first );
  return str;
}

std::string VulkanHppGenerator::generateHandleCommandDeclarations( std::set<std::string> const & commands ) const
{
  std::string           str;
  std::set<std::string> listedCommands;  // some commands are listed with more than one extension!
  for ( auto const & feature : m_features )
  {
    std::vector<std::string> commandNames = selectCommandsByHandle( feature.second.requireData, commands, listedCommands );
    if ( !commandNames.empty() )
    {
      str += "\n  //=== " + feature.first + " ===\n";
      for ( auto const & command : commandNames )
      {
        auto commandIt = m_commands.find( command );
        assert( commandIt != m_commands.end() );

        str += "\n";
        str += generateCommand( commandIt->first, commandIt->second, 1, false );
        str += generateDestroyCommand( commandIt->first, commandIt->second );
      }
    }
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    std::vector<std::string> commandNames = selectCommandsByHandle( extIt.second->second.requireData, commands, listedCommands );
    if ( !commandNames.empty() )
    {
      auto [enter, leave] = generateProtection( extIt.second->first, std::string() );
      str += "\n" + enter + "  //=== " + extIt.second->first + " ===\n";
      for ( auto const & command : commandNames )
      {
        auto commandIt = m_commands.find( command );
        assert( commandIt != m_commands.end() );

        std::string commandString;
        std::string commandName = generateCommandName( commandIt->first, commandIt->second.params, 1, m_tags, false, false );
        str += "\n";
        str += generateCommand( commandIt->first, commandIt->second, 1, false );
        str += generateDestroyCommand( commandIt->first, commandIt->second );
      }
      str += leave;
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateHandleDependencies( std::pair<std::string, HandleData> const & handleData, std::set<std::string> & listedHandles ) const
{
  std::string str;
  for ( auto const & command : handleData.second.commands )
  {
    auto commandIt = m_commands.find( command );
    assert( commandIt != m_commands.end() );
    for ( auto const & parameter : commandIt->second.params )
    {
      auto handleIt = m_handles.find( parameter.type.type );
      if ( ( handleIt != m_handles.end() ) && ( parameter.type.type != handleData.first ) &&
           ( listedHandles.find( parameter.type.type ) == listedHandles.end() ) )
      {
        str += generateHandle( *handleIt, listedHandles );
      }
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateHandleEmpty( HandleData const & handleData ) const
{
  std::string           str;
  std::set<std::string> listedCommands;  // some commands are listed with more than one extension !
  for ( auto const & feature : m_features )
  {
    std::vector<std::string> commands = selectCommandsByHandle( feature.second.requireData, handleData.commands, listedCommands );
    if ( !commands.empty() )
    {
      str += "\n  //=== " + feature.first + " ===\n";
      for ( auto const & command : commands )
      {
        auto commandIt = m_commands.find( command );
        assert( commandIt != m_commands.end() );
        if ( commandIt->first == "vkCreateInstance" )
        {
          // special handling for createInstance, as we need to explicitly place the forward declarations and the
          // deleter classes here
#if !defined( NDEBUG )
          auto handleIt = m_handles.find( "" );
          assert( ( handleIt != m_handles.end() ) && ( handleIt->second.childrenHandles.size() == 2 ) );
          assert( handleIt->second.childrenHandles.find( "VkInstance" ) != handleIt->second.childrenHandles.end() );
#endif

          str += generateUniqueTypes( "", { "VkInstance" } );
        }
        str += "\n";

        str += generateCommand( commandIt->first, commandIt->second, 0, false );
      }
    }
  }
#if !defined( NDEBUG )
  for ( auto const & extIt : m_extensionsByNumber )
  {
    assert( selectCommandsByHandle( extIt.second->second.requireData, handleData.commands, listedCommands ).empty() );
  }
#endif
  return str;
}

std::string VulkanHppGenerator::generateHandleHashStructures( std::vector<RequireData> const & requireData, std::string const & title ) const
{
  const std::string hashTemplate = R"(
  template <> struct hash<VULKAN_HPP_NAMESPACE::${type}>
  {
    std::size_t operator()(VULKAN_HPP_NAMESPACE::${type} const & ${name}) const VULKAN_HPP_NOEXCEPT
    {
      return std::hash<Vk${type}>{}(static_cast<Vk${type}>(${name}));
    }
  };
)";

  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto handleIt = m_handles.find( type );
      if ( handleIt != m_handles.end() )
      {
        std::string handleType = stripPrefix( handleIt->first, "Vk" );
        std::string handleName = startLowerCase( handleType );
        str += replaceWithMap( hashTemplate, { { "name", handleName }, { "type", handleType } } );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateHandleHashStructures() const
{
  const std::string hashesTemplate = R"(
  //===================================
  //=== HASH structures for handles ===
  //===================================

${hashes}
)";

  std::string hashes;
  for ( auto const & feature : m_features )
  {
    hashes += generateHandleHashStructures( feature.second.requireData, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    hashes += generateHandleHashStructures( extIt.second->second.requireData, extIt.second->first );
  }
  return replaceWithMap( hashesTemplate, { { "hashes", hashes } } );
}

std::string VulkanHppGenerator::generateHandles() const
{
  // Note: reordering structs or handles by features and extensions is not possible!
  std::string str = R"(
  //===============
  //=== HANDLEs ===
  //===============
)";

  std::set<std::string> listedHandles;
  for ( auto const & handle : m_handles )
  {
    if ( listedHandles.find( handle.first ) == listedHandles.end() )
    {
      str += generateHandle( handle, listedHandles );
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateIndexTypeTraits() const
{
  const std::string indexTypeTraitsTemplate = R"(
  template<typename T>
  struct IndexTypeValue
  {};

${indexTypeTraits}
)";

  auto indexType = m_enums.find( "VkIndexType" );
  assert( indexType != m_enums.end() );

  std::string           indexTypeTraits;
  std::set<std::string> listedCppTypes;
  for ( auto const & value : indexType->second.values )
  {
    std::string valueName = generateEnumValueName( indexType->first, value.name, false, m_tags );
    std::string cppType;
    if ( !valueName.starts_with( "eNone" ) )
    {
      // get the bit count out of the value Name (8, 16, 32, ... ) and generate the cppType (uint8_t,...)
      assert( valueName.starts_with( "eUint" ) );
      auto beginDigit = valueName.begin() + strlen( "eUint" );
      assert( isdigit( *beginDigit ) );
      auto endDigit = std::find_if_not( beginDigit, valueName.end(), []( std::string::value_type c ) { return isdigit( c ); } );
      cppType       = "uint" + valueName.substr( strlen( "eUint" ), endDigit - beginDigit ) + "_t";
    }

    if ( !cppType.empty() )
    {
      if ( listedCppTypes.insert( cppType ).second )
      {
        // IndexType traits aren't necessarily invertible.
        // The Type -> Enum translation will only occur for the first prefixed enum value.
        // A hypothetical extension to this enum with a conflicting prefix will use the core spec value.
        const std::string typeToEnumTemplate = R"(
  template <>
  struct IndexTypeValue<${cppType}>
  {
    static VULKAN_HPP_CONST_OR_CONSTEXPR IndexType value = IndexType::${valueName};
  };
)";
        indexTypeTraits += replaceWithMap( typeToEnumTemplate, { { "cppType", cppType }, { "valueName", valueName } } );
      }

      // Enum -> Type translations are always able to occur.
      const std::string enumToTypeTemplate = R"(
  template <>
  struct CppType<IndexType, IndexType::${valueName}>
  {
    using Type = ${cppType};
  };
)";
      indexTypeTraits += replaceWithMap( enumToTypeTemplate, { { "cppType", cppType }, { "valueName", valueName } } );
    }
  }

  return replaceWithMap( indexTypeTraitsTemplate, { { "indexTypeTraits", indexTypeTraits } } );
}

std::string VulkanHppGenerator::generateLenInitializer(
  std::vector<MemberData>::const_iterator                                                                                 mit,
  std::map<std::vector<MemberData>::const_iterator, std::vector<std::vector<MemberData>::const_iterator>>::const_iterator litit,
  bool                                                                                                                    mutualExclusiveLens ) const
{
  std::string initializer;
  if ( mutualExclusiveLens )
  {
    // there are multiple mutually exclusive arrays related to this len
    for ( size_t i = 0; i + 1 < litit->second.size(); i++ )
    {
      auto        arrayIt      = litit->second[i];
      std::string argumentName = startLowerCase( stripPrefix( arrayIt->name, "p" ) ) + "_";
      initializer += "!" + argumentName + ".empty() ? " + argumentName + ".size() : ";
    }
    auto        arrayIt      = litit->second.back();
    std::string argumentName = startLowerCase( stripPrefix( arrayIt->name, "p" ) ) + "_";
    initializer += argumentName + ".size()";
  }
  else
  {
    auto arrayIt = litit->second.front();
    assert( ( arrayIt->len.front() == litit->first->name ) || ( ( arrayIt->len.front() == "codeSize / 4" ) && ( litit->first->name == "codeSize" ) ) );

    assert( arrayIt->name.starts_with( "p" ) );
    std::string argumentName = startLowerCase( stripPrefix( arrayIt->name, "p" ) ) + "_";

    assert( mit->type.prefix.empty() && mit->type.postfix.empty() );
    initializer = argumentName + ".size()";
    if ( arrayIt->len.front() == "codeSize / 4" )
    {
      initializer += " * 4";
    }
    if ( ( arrayIt->type.type == "void" ) &&
         ( std::count_if( arrayIt->type.postfix.begin(), arrayIt->type.postfix.end(), []( char c ) { return c == '*'; } ) < 2 ) )
    {
      initializer += " * sizeof(T)";
    }
  }
  if ( mit->type.type != "size_t" )
  {
    initializer = "static_cast<" + mit->type.type + ">( " + initializer + " )";
  }
  return initializer;
}

std::string VulkanHppGenerator::generateName( TypeInfo const & typeInfo ) const
{
  std::string name = stripPrefix( typeInfo.type, "Vk" );
  assert( typeInfo.prefix.find( '*' ) == std::string::npos );
  if ( typeInfo.postfix.find( '*' ) != std::string::npos )
  {
    assert( typeInfo.postfix.find_first_of( '*' ) == typeInfo.postfix.find_last_of( '*' ) );
    name = "p" + name;
  }
  else
  {
    name = startLowerCase( name );
  }
  return name;
}

std::string VulkanHppGenerator::generateNoExcept( std::vector<std::string> const &          errorCodes,
                                                  std::vector<size_t> const &               returnParams,
                                                  std::map<size_t, VectorParamData> const & vectorParams,
                                                  bool                                      singular,
                                                  bool                                      vectorSizeCheck,
                                                  bool                                      raii ) const
{
  // noexcept is only possible with no error codes, and the return param (if any) is not a vector param (unless it's the singular version)
  return ( errorCodes.empty() &&
           ( singular || returnParams.empty() ||
             ( std::find_if( returnParams.begin(),
                             returnParams.end(),
                             [&vectorParams]( size_t rp ) { return vectorParams.find( rp ) != vectorParams.end(); } ) == returnParams.end() ) ) )
         ? ( vectorSizeCheck ? ( raii ? "" : " VULKAN_HPP_NOEXCEPT_WHEN_NO_EXCEPTIONS" ) : " VULKAN_HPP_NOEXCEPT" )
         : "";
}

std::string VulkanHppGenerator::generateObjectDeleter( std::string const & commandName,
                                                       CommandData const & commandData,
                                                       size_t              initialSkipCount,
                                                       size_t              returnParam ) const
{
  std::string objectDeleter, allocator;
  if ( ( commandName.find( "Acquire" ) != std::string::npos ) || ( commandName.find( "Get" ) != std::string::npos ) )
  {
    if ( ( commandName == "vkAcquirePerformanceConfigurationINTEL" ) || ( commandName == "vkGetRandROutputDisplayEXT" ) ||
         ( commandName == "vkGetWinrtDisplayNV" ) || ( commandName == "vkGetDrmDisplayEXT" ) )
    {
      objectDeleter = "ObjectRelease";
    }
    else
    {
      throw std::runtime_error( "Found " + commandName + " which requires special handling for the object deleter" );
    }
  }
  else if ( commandName.find( "Allocate" ) != std::string::npos )
  {
    objectDeleter = "ObjectFree";
    allocator     = "allocator, ";
  }
  else
  {
    assert( ( commandName.find( "Create" ) != std::string::npos ) || ( commandName.find( "Register" ) != std::string::npos ) );
    objectDeleter = "ObjectDestroy";
    allocator     = "allocator, ";
  }
  std::string className  = initialSkipCount ? stripPrefix( commandData.params[initialSkipCount - 1].type.type, "Vk" ) : "";
  std::string parentName = ( className.empty() || ( commandData.params[returnParam].type.type == "VkDevice" ) ) ? "NoParent" : className;
  return objectDeleter + "<" + parentName + ", Dispatch>( " + ( ( parentName == "NoParent" ) ? "" : "*this, " ) + allocator + "d )";
}

std::pair<std::string, std::string> VulkanHppGenerator::generateProtection( std::string const & referencedIn, std::string const & protect ) const
{
  if ( !referencedIn.empty() )
  {
    if ( m_features.find( referencedIn ) == m_features.end() )
    {
      auto extensionIt = m_extensions.find( referencedIn );
      assert( extensionIt != m_extensions.end() );
      if ( !extensionIt->second.platform.empty() )
      {
        auto platformIt = m_platforms.find( extensionIt->second.platform );
        assert( platformIt != m_platforms.end() );
        if ( !platformIt->second.protect.empty() )
        {
          return std::make_pair( "#if defined( " + platformIt->second.protect + " )\n", "#endif /*" + platformIt->second.protect + "*/\n" );
        }
      }
    }
  }
  else if ( !protect.empty() )
  {
    return std::make_pair( "#if defined( " + protect + " )\n", "#endif /*" + protect + "*/\n" );
  }
  return std::make_pair( "", "" );
}

std::pair<std::string, std::string> VulkanHppGenerator::generateProtection( std::string const & type, bool isAliased ) const
{
  if ( isAliased )
  {
    return std::make_pair( "", "" );
  }
  else
  {
    auto typeIt = m_types.find( type );
    assert( typeIt != m_types.end() );
    return generateProtection( typeIt->second.referencedIn, std::string() );
  }
}

std::string VulkanHppGenerator::generateRAIICommandDefinitions() const
{
  const std::string commandDefinitionsTemplate = R"(
  //===========================
  //=== COMMAND Definitions ===
  //===========================

${commandDefinitions}
)";

  std::string           commandDefinitions;
  std::set<std::string> listedCommands;  // some commands are listed with more than one extension!
  for ( auto const & feature : m_features )
  {
    commandDefinitions += generateRAIICommandDefinitions( feature.second.requireData, listedCommands, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    commandDefinitions += generateRAIICommandDefinitions( extIt.second->second.requireData, listedCommands, extIt.second->first );
  }

  return replaceWithMap( commandDefinitionsTemplate, { { "commandDefinitions", commandDefinitions } } );
}

std::string VulkanHppGenerator::generateRAIICommandDefinitions( std::vector<RequireData> const & requireData,
                                                                std::set<std::string> &          listedCommands,
                                                                std::string const &              title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & command : require.commands )
    {
      if ( listedCommands.insert( command ).second )
      {
        str += generateRAIIHandleCommand( command, determineInitialSkipCount( command ), true );
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateRAIIDispatchers() const
{
  std::string contextInitializers, contextMembers, deviceAssignments, deviceMembers, instanceAssignments, instanceMembers;

  std::set<std::string> listedCommands;
  for ( auto const & feature : m_features )
  {
    appendRAIIDispatcherCommands( feature.second.requireData,
                                  listedCommands,
                                  feature.first,
                                  contextInitializers,
                                  contextMembers,
                                  deviceAssignments,
                                  deviceMembers,
                                  instanceAssignments,
                                  instanceMembers );
  }
  for ( auto const & extension : m_extensions )
  {
    appendRAIIDispatcherCommands( extension.second.requireData,
                                  listedCommands,
                                  extension.first,
                                  contextInitializers,
                                  contextMembers,
                                  deviceAssignments,
                                  deviceMembers,
                                  instanceAssignments,
                                  instanceMembers );
  }

  std::string contextDispatcherTemplate = R"(
    class ContextDispatcher : public DispatchLoaderBase
    {
    public:
      ContextDispatcher( PFN_vkGetInstanceProcAddr getProcAddr )
        : vkGetInstanceProcAddr( getProcAddr )${contextInitializers}
      {}

    public:
      PFN_vkGetInstanceProcAddr vkGetInstanceProcAddr = 0;
${contextMembers}
    };
)";

  std::string str = replaceWithMap( contextDispatcherTemplate, { { "contextInitializers", contextInitializers }, { "contextMembers", contextMembers } } );

  std::string instanceDispatcherTemplate = R"(
    class InstanceDispatcher : public DispatchLoaderBase
    {
    public:
      InstanceDispatcher( PFN_vkGetInstanceProcAddr getProcAddr, VkInstance instance )
        : vkGetInstanceProcAddr( getProcAddr )
      {
${instanceAssignments}
        vkGetDeviceProcAddr =
          PFN_vkGetDeviceProcAddr( vkGetInstanceProcAddr( instance, "vkGetDeviceProcAddr" ) );
      }

    public:
${instanceMembers}
      PFN_vkGetDeviceProcAddr vkGetDeviceProcAddr = 0;
    };
)";

  str += replaceWithMap( instanceDispatcherTemplate, { { "instanceAssignments", instanceAssignments }, { "instanceMembers", instanceMembers } } );

  std::string deviceDispatcherTemplate = R"(
    class DeviceDispatcher : public DispatchLoaderBase
    {
    public:
      DeviceDispatcher( PFN_vkGetDeviceProcAddr getProcAddr, VkDevice device ) : vkGetDeviceProcAddr( getProcAddr )
      {
${deviceAssignments}
      }

    public:
${deviceMembers}
    };
)";

  str += replaceWithMap( deviceDispatcherTemplate, { { "deviceAssignments", deviceAssignments }, { "deviceMembers", deviceMembers } } );
  return str;
}

std::string VulkanHppGenerator::generateRAIIHandle( std::pair<std::string, HandleData> const & handle,
                                                    std::set<std::string> &                    listedHandles,
                                                    std::set<std::string> const &              specialFunctions ) const
{
  std::string str;
  if ( listedHandles.find( handle.first ) == listedHandles.end() )
  {
    rescheduleRAIIHandle( str, handle, listedHandles, specialFunctions );

    auto [enter, leave]    = generateProtection( handle.first, !handle.second.alias.empty() );
    std::string handleType = stripPrefix( handle.first, "Vk" );
    std::string handleName = generateRAIIHandleConstructorParamName( handle.first, handle.second.destructorIt );

    auto [singularConstructors, arrayConstructors] = generateRAIIHandleConstructors( handle );

    auto [clearMembers, getConstructorSuccessCode, memberVariables, moveConstructorInitializerList, moveAssignmentInstructions, swapMembers] =
      generateRAIIHandleDetails( handle );

    std::string declarations = generateRAIIHandleCommandDeclarations( handle, specialFunctions );

    assert( !handle.second.objTypeEnum.empty() );
    auto enumIt = m_enums.find( "VkObjectType" );
    assert( enumIt != m_enums.end() );
    auto valueIt = std::find_if(
      enumIt->second.values.begin(), enumIt->second.values.end(), [&handle]( EnumValueData const & evd ) { return evd.name == handle.second.objTypeEnum; } );
    assert( valueIt != enumIt->second.values.end() );
    std::string objTypeEnum = generateEnumValueName( enumIt->first, valueIt->name, false, m_tags );

    enumIt = m_enums.find( "VkDebugReportObjectTypeEXT" );
    assert( enumIt != m_enums.end() );
    std::string valueName = handle.second.objTypeEnum;
    valueName             = valueName.replace( 3, 0, "DEBUG_REPORT_" ) + "_EXT";
    valueIt =
      std::find_if( enumIt->second.values.begin(), enumIt->second.values.end(), [&valueName]( EnumValueData const & evd ) { return valueName == evd.name; } );
    std::string debugReportObjectType =
      ( valueIt != enumIt->second.values.end() ) ? generateEnumValueName( enumIt->first, valueIt->name, false, m_tags ) : "eUnknown";

    std::string dispatcherType = ( ( handle.first == "VkDevice" ) || ( handle.second.constructorIts.front()->second.params.front().type.type == "VkDevice" ) )
                                 ? "VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::DeviceDispatcher"
                                 : "VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::InstanceDispatcher";

    std::string getParent;
    if ( ( handle.first != "VkInstance" ) && ( handle.first != "VkDevice" ) && ( handle.second.destructorIt != m_commands.end() ) )
    {
      assert( !handle.second.destructorIt->second.params.empty() );
      std::string parentType = stripPrefix( handle.second.destructorIt->second.params.front().type.type, "Vk" );
      getParent              = "    VULKAN_HPP_NAMESPACE::" + parentType + " get" + parentType + "() const\n";
      getParent += "    {\n";
      getParent += "      return m_" + handle.second.destructorIt->second.params.front().name + ";\n";
      getParent += "    }\n";
    }

    std::string assignmentOperator, copyConstructor;
    if ( handle.second.destructorIt == m_commands.end() )
    {
      // allow copy constructor and assignment operator for classes without destructor
      std::string const copyConstructorTemplate =
        R"(      ${handleType}( ${handleType} const & rhs ) : m_${handleName}( rhs.m_${handleName} ), m_dispatcher( rhs.m_dispatcher ) {})";
      copyConstructor += replaceWithMap( copyConstructorTemplate, { { "handleName", handleName }, { "handleType", handleType } } );

      std::string assignmentOperatorTemplate = R"(      ${handleType} & operator=( ${handleType} const & rhs )
      {
        m_${handleName} = rhs.m_${handleName};
        m_dispatcher    = rhs.m_dispatcher;
        return *this;
      })";
      assignmentOperator += replaceWithMap( assignmentOperatorTemplate, { { "handleName", handleName }, { "handleType", handleType } } );
    }
    else
    {
      std::string const copyConstructorTemplate = R"(      ${handleType}( ${handleType} const & ) = delete;)";
      copyConstructor += replaceWithMap( copyConstructorTemplate, { { "handleType", handleType } } );

      std::string const assignmentOperatorTemplate = R"(      ${handleType} & operator=( ${handleType} const & ) = delete;)";
      assignmentOperator += replaceWithMap( assignmentOperatorTemplate, { { "handleType", handleType } } );
    }

    const std::string handleTemplate = R"(
${enter}  class ${handleType}
  {
  public:
    using CType = Vk${handleType};

    static VULKAN_HPP_CONST_OR_CONSTEXPR VULKAN_HPP_NAMESPACE::ObjectType objectType = VULKAN_HPP_NAMESPACE::ObjectType::${objTypeEnum};
    static VULKAN_HPP_CONST_OR_CONSTEXPR VULKAN_HPP_NAMESPACE::DebugReportObjectTypeEXT debugReportObjectType = VULKAN_HPP_NAMESPACE::DebugReportObjectTypeEXT::${debugReportObjectType};

  public:
${singularConstructors}
    ${handleType}( std::nullptr_t ) {}

    ~${handleType}()
    {
      clear();
    }

    ${handleType}() = delete;
${copyConstructor}
    ${handleType}( ${handleType} && rhs ) VULKAN_HPP_NOEXCEPT
      : ${moveConstructorInitializerList}
    {}
${assignmentOperator}
    ${handleType} & operator=( ${handleType} && rhs ) VULKAN_HPP_NOEXCEPT
    {
      if ( this != &rhs )
      {
${moveAssignmentInstructions}
      }
      return *this;
    }

    VULKAN_HPP_NAMESPACE::${handleType} const & operator*() const VULKAN_HPP_NOEXCEPT
    {
      return m_${handleName};
    }

    void clear() VULKAN_HPP_NOEXCEPT
    {
${clearMembers}
    }

${getConstructorSuccessCode}
${getParent}
    ${dispatcherType} const * getDispatcher() const
    {
      VULKAN_HPP_ASSERT( m_dispatcher->getVkHeaderVersion() == VK_HEADER_VERSION );
      return ${getDispatcherReturn}m_dispatcher;
    }

    void swap( VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::${handleType} & rhs ) VULKAN_HPP_NOEXCEPT
    {
${swapMembers}
    }

${memberFunctionsDeclarations}

  private:
    ${memberVariables}
  };
${leave})";

    str += replaceWithMap( handleTemplate,
                           { { "assignmentOperator", assignmentOperator },
                             { "clearMembers", clearMembers },
                             { "copyConstructor", copyConstructor },
                             { "debugReportObjectType", debugReportObjectType },
                             { "dispatcherType", dispatcherType },
                             { "enter", enter },
                             { "getConstructorSuccessCode", getConstructorSuccessCode },
                             { "getDispatcherReturn", ( handleType == "Device" ) || ( handleType == "Instance" ) ? "&*" : "" },
                             { "getParent", getParent },
                             { "handleName", handleName },
                             { "handleType", handleType },
                             { "leave", leave },
                             { "memberFunctionsDeclarations", declarations },
                             { "memberVariables", memberVariables },
                             { "moveAssignmentInstructions", moveAssignmentInstructions },
                             { "moveConstructorInitializerList", moveConstructorInitializerList },
                             { "objTypeEnum", objTypeEnum },
                             { "singularConstructors", singularConstructors },
                             { "swapMembers", swapMembers } } );

    if ( !arrayConstructors.empty() )
    {
      // it's a handle class with a friendly handles class
      const std::string handlesTemplate = R"(
${enter}  class ${handleType}s : public std::vector<VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::${handleType}>
  {
  public:
    ${arrayConstructors}
    ${handleType}s( std::nullptr_t ) {}

    ${handleType}s() = delete;
    ${handleType}s( ${handleType}s const & ) = delete;
    ${handleType}s( ${handleType}s && rhs ) = default;
    ${handleType}s & operator=( ${handleType}s const & ) = delete;
    ${handleType}s & operator=( ${handleType}s && rhs ) = default;
  };
${leave}
)";

      str +=
        replaceWithMap( handlesTemplate, { { "arrayConstructors", arrayConstructors }, { "enter", enter }, { "handleType", handleType }, { "leave", leave } } );
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateRAIIHandleCommand( std::string const & command, size_t initialSkipCount, bool definition ) const
{
  std::string str;
  if ( m_RAIISpecialFunctions.find( command ) == m_RAIISpecialFunctions.end() )
  {
    auto commandIt = m_commands.find( command );
    assert( commandIt != m_commands.end() );

    if ( commandIt->second.returnType == "VkResult" )
    {
      str = generateRAIIHandleCommandResult( commandIt, initialSkipCount, definition );
    }
    else if ( commandIt->second.returnType == "void" )
    {
      str = generateRAIIHandleCommandVoid( commandIt, initialSkipCount, definition );
    }
    else
    {
      str = generateRAIIHandleCommandValue( commandIt, initialSkipCount, definition );
    }

    if ( str.empty() )
    {
      throw std::runtime_error( "Never encountered a command like <" + command + "> !" );
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateRAIIHandleCommandDeclarations( std::pair<std::string, HandleData> const & handle,
                                                                       std::set<std::string> const &              specialFunctions ) const
{
  std::string           functionDeclarations;
  std::set<std::string> listedCommands;  // some commands are listed with more than one extension !
  for ( auto const & feature : m_features )
  {
    std::vector<std::string> firstLevelCommands, secondLevelCommands;

    for ( auto const & require : feature.second.requireData )
    {
      for ( auto const & command : require.commands )
      {
        if ( specialFunctions.find( command ) == specialFunctions.end() )
        {
          if ( handle.second.commands.find( command ) != handle.second.commands.end() )
          {
            assert( listedCommands.find( command ) == listedCommands.end() );
            listedCommands.insert( command );
            firstLevelCommands.push_back( command );
          }
          else if ( handle.second.secondLevelCommands.find( command ) != handle.second.secondLevelCommands.end() )
          {
            assert( listedCommands.find( command ) == listedCommands.end() );
            listedCommands.insert( command );
            assert( !handle.first.empty() );
            secondLevelCommands.push_back( command );
          }
        }
      }
    }
    if ( !firstLevelCommands.empty() || !secondLevelCommands.empty() )
    {
      functionDeclarations += "\n  //=== " + feature.first + " ===\n";
      for ( auto const & command : firstLevelCommands )
      {
        functionDeclarations += generateRAIIHandleCommand( command, handle.first.empty() ? 0 : 1, false );
      }
      for ( auto const & command : secondLevelCommands )
      {
        assert( !handle.first.empty() );
        functionDeclarations += generateRAIIHandleCommand( command, 2, false );
      }
    }
  }

  for ( auto const & extIt : m_extensionsByNumber )
  {
    std::vector<std::string> firstLevelCommands, secondLevelCommands;
    for ( auto & req : extIt.second->second.requireData )
    {
      for ( auto const & command : req.commands )
      {
        if ( ( specialFunctions.find( command ) == specialFunctions.end() ) && ( listedCommands.find( command ) == listedCommands.end() ) )
        {
          if ( handle.second.commands.find( command ) != handle.second.commands.end() )
          {
            listedCommands.insert( command );
            firstLevelCommands.push_back( command );
          }
          else if ( handle.second.secondLevelCommands.find( command ) != handle.second.secondLevelCommands.end() )
          {
            listedCommands.insert( command );
            secondLevelCommands.push_back( command );
          }
        }
      }
    }
    if ( !firstLevelCommands.empty() || !secondLevelCommands.empty() )
    {
      std::string enter, leave;
      if ( extIt.second->first != m_types.find( handle.first )->second.referencedIn )
      {
        std::tie( enter, leave ) = generateProtection( extIt.second->first, std::string() );
      }
      functionDeclarations += "\n" + enter + "  //=== " + extIt.second->first + " ===\n";
      for ( auto const & command : firstLevelCommands )
      {
        functionDeclarations += generateRAIIHandleCommand( command, handle.first.empty() ? 0 : 1, false );
      }
      for ( auto const & command : secondLevelCommands )
      {
        assert( !handle.first.empty() );
        functionDeclarations += generateRAIIHandleCommand( command, 2, false );
      }
      functionDeclarations += leave;
    }
  }
  return functionDeclarations;
}

std::string VulkanHppGenerator::generateRAIIHandleCommandEnhanced( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                   size_t                                             initialSkipCount,
                                                                   std::vector<size_t> const &                        returnParams,
                                                                   std::map<size_t, VectorParamData> const &          vectorParams,
                                                                   bool                                               definition,
                                                                   bool                                               chained,
                                                                   bool                                               singular ) const
{
  std::set<size_t> skippedParams  = determineSkippedParams( commandIt->second.params, initialSkipCount, vectorParams, returnParams, singular );
  std::set<size_t> singularParams = singular ? determineSingularParams( returnParams[0], vectorParams ) : std::set<size_t>();
  // special handling for vkGetMemoryHostPointerPropertiesEXT: here, we really need to stick with the const void * parameter !
  std::set<size_t> templatedParams =
    ( commandIt->first == "vkGetMemoryHostPointerPropertiesEXT" ) ? std::set<size_t>() : determineVoidPointerParams( commandIt->second.params );

  bool                     enumerating = determineEnumeration( vectorParams, returnParams );
  std::vector<std::string> dataTypes   = determineDataTypes( commandIt->second.params, vectorParams, returnParams, templatedParams );
  std::string              dataType    = combineDataTypes( vectorParams, returnParams, singular, enumerating, dataTypes, false, true );

  std::string argumentTemplates = generateArgumentTemplates( commandIt->second.params, returnParams, vectorParams, templatedParams, chained, true );
  std::string argumentList      = generateArgumentListEnhanced(
    commandIt->second.params, returnParams, vectorParams, skippedParams, singularParams, templatedParams, definition, false, false, false );
  std::string commandName = generateCommandName( commandIt->first, commandIt->second.params, initialSkipCount, m_tags, singular, false );
  std::string nodiscard =
    generateNoDiscard( !returnParams.empty() || ( ( commandIt->second.returnType != "VkResult" ) && ( commandIt->second.returnType != "void" ) ),
                       1 < commandIt->second.successCodes.size(),
                       false );
  std::pair<bool, std::map<size_t, std::vector<size_t>>> vectorSizeCheck =
    needsVectorSizeCheck( commandIt->second.params, vectorParams, returnParams, singularParams );
  std::string noexceptString = generateNoExcept( commandIt->second.errorCodes, returnParams, vectorParams, singular, vectorSizeCheck.first, true );
  std::string returnType     = generateReturnType( commandIt->second, returnParams, vectorParams, false, chained, true, dataType );

  if ( definition )
  {
    std::string const definitionTemplate =
      R"(
  ${argumentTemplates}
  ${nodiscard} VULKAN_HPP_INLINE ${returnType} ${className}::${commandName}( ${argumentList} ) const ${noexcept}
  {
${functionPointerCheck}
${vectorSizeCheck}
    ${dataSizeChecks}
    ${dataDeclarations}
    ${callSequence}
    ${resultCheck}
    ${dataPreparation}
    ${returnStatement}
  }
)";

    std::string callSequence =
      generateCallSequence( commandIt->first, commandIt->second, returnParams, vectorParams, initialSkipCount, singularParams, templatedParams, chained, true );
    std::string className        = initialSkipCount ? stripPrefix( commandIt->second.params[initialSkipCount - 1].type.type, "Vk" ) : "Context";
    std::string returnVariable   = generateReturnVariable( commandIt->second, returnParams, vectorParams, chained, singular );
    std::string dataDeclarations = generateDataDeclarations(
      commandIt->second, returnParams, vectorParams, templatedParams, singular, false, chained, false, true, dataTypes, dataType, returnType, returnVariable );
    std::string dataPreparation =
      generateDataPreparation( commandIt->second, initialSkipCount, returnParams, vectorParams, templatedParams, singular, false, false, chained, enumerating );
    std::string dataSizeChecks  = generateDataSizeChecks( commandIt->second, returnParams, dataTypes, vectorParams, templatedParams, singular );
    std::string resultCheck     = generateResultCheck( commandIt->second, className, "::", commandName, enumerating );
    std::string returnStatement = generateReturnStatement( commandIt->first,
                                                           commandIt->second,
                                                           returnVariable,
                                                           returnType,
                                                           dataType,
                                                           initialSkipCount,
                                                           returnParams.empty() ? INVALID_INDEX : returnParams[0],
                                                           false,
                                                           enumerating,
                                                           true );
    std::string vectorSizeCheckString =
      vectorSizeCheck.first ? generateRAIIHandleVectorSizeCheck( commandIt->first, commandIt->second, initialSkipCount, vectorSizeCheck.second, skippedParams )
                            : "";

    return replaceWithMap( definitionTemplate,
                           { { "argumentList", argumentList },
                             { "argumentTemplates", argumentTemplates },
                             { "callSequence", callSequence },
                             { "className", className },
                             { "commandName", commandName },
                             { "dataDeclarations", dataDeclarations },
                             { "dataPreparation", dataPreparation },
                             { "dataSizeChecks", dataSizeChecks },
                             { "functionPointerCheck", generateFunctionPointerCheck( commandIt->first, commandIt->second.referencedIn ) },
                             { "nodiscard", nodiscard },
                             { "noexcept", noexceptString },
                             { "resultCheck", resultCheck },
                             { "returnStatement", returnStatement },
                             { "returnType", returnType },
                             { "vectorSizeCheck", vectorSizeCheckString } } );
  }
  else
  {
    std::string const declarationTemplate =
      R"(
    ${argumentTemplates}
    ${nodiscard} ${returnType} ${commandName}( ${argumentList} ) const ${noexcept};
)";

    return replaceWithMap( declarationTemplate,
                           { { "argumentList", argumentList },
                             { "argumentTemplates", argumentTemplates },
                             { "commandName", commandName },
                             { "nodiscard", nodiscard },
                             { "noexcept", noexceptString },
                             { "returnType", returnType } } );
  }
}

std::string VulkanHppGenerator::generateRAIIHandleCommandFactory( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                  size_t                                             initialSkipCount,
                                                                  std::vector<size_t> const &                        returnParams,
                                                                  std::map<size_t, VectorParamData> const &          vectorParams,
                                                                  bool                                               definition,
                                                                  bool                                               singular ) const
{
  assert( isHandleType( commandIt->second.params[returnParams.back()].type.type ) );
  assert( ( returnParams.size() == 1 ) ||
          ( ( returnParams.size() == 2 ) && ( vectorParams.size() == 1 ) && ( returnParams[0] == vectorParams.begin()->second.lenParam ) &&
            ( returnParams[1] == vectorParams.begin()->first ) ) );

  std::set<size_t> skippedParams  = determineSkippedParams( commandIt->second.params, initialSkipCount, vectorParams, returnParams, singular );
  std::set<size_t> singularParams = singular ? determineSingularParams( returnParams.back(), vectorParams ) : std::set<size_t>();
  std::string      argumentList   = generateRAIIHandleCommandFactoryArgumentList( commandIt->second.params, skippedParams, definition, singular );
  std::string      commandName    = generateCommandName( commandIt->first, commandIt->second.params, initialSkipCount, m_tags, singular, false );
  std::string      handleType     = stripPostfix( commandIt->second.params[returnParams.back()].type.compose( "VULKAN_HPP_RAII_NAMESPACE" ), " *" );
  std::string      returnType     = handleType;
  if ( ( vectorParams.find( returnParams.back() ) != vectorParams.end() ) && !singular )
  {
    returnType = "std::vector<" + handleType + ">";
    handleType += "s";
  }

  if ( definition )
  {
    std::string callArguments = generateCallArgumentsRAIIFactory( commandIt->second.params, initialSkipCount, skippedParams, singularParams );
    std::string className     = initialSkipCount ? stripPrefix( commandIt->second.params[initialSkipCount - 1].type.type, "Vk" ) : "Context";

    std::string const definitionTemplate =
      R"(
  VULKAN_HPP_NODISCARD VULKAN_HPP_INLINE ${returnType} ${className}::${commandName}( ${argumentList} ) const
  {
    return ${handleType}( ${callArguments} );
  }
)";

    return replaceWithMap( definitionTemplate,
                           { { "argumentList", argumentList },
                             { "callArguments", callArguments },
                             { "className", className },
                             { "commandName", commandName },
                             { "handleType", handleType },
                             { "returnType", returnType } } );
  }
  else
  {
    std::string const declarationTemplate =
      R"(
  VULKAN_HPP_NODISCARD ${returnType} ${commandName}( ${argumentList} ) const;
)";

    return replaceWithMap( declarationTemplate, { { "argumentList", argumentList }, { "commandName", commandName }, { "returnType", returnType } } );
  }
}

std::string VulkanHppGenerator::generateRAIIHandleCommandFactoryArgumentList( std::vector<ParamData> const & params,
                                                                              std::set<size_t> const &       skippedParams,
                                                                              bool                           definition,
                                                                              bool                           singular ) const
{
  std::string arguments;
  bool        encounteredArgument = false;
  for ( size_t i = 0; i < params.size(); ++i )
  {
    if ( skippedParams.find( i ) == skippedParams.end() )
    {
      if ( encounteredArgument )
      {
        arguments += ", ";
      }
      arguments += generateRAIIHandleConstructorArgument( params[i], definition, singular, false );
      encounteredArgument = true;
    }
  }
  return arguments;
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResult( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                 size_t                                             initialSkipCount,
                                                                 bool                                               definition ) const
{
  assert( !commandIt->second.successCodes.empty() );
  if ( commandIt->second.successCodes.size() == 1 )
  {
    if ( commandIt->second.errorCodes.empty() )
    {
      return generateRAIIHandleCommandResultSingleSuccessNoErrors( commandIt, initialSkipCount, definition );
    }
    else
    {
      return generateRAIIHandleCommandResultSingleSuccessWithErrors( commandIt, initialSkipCount, definition );
    }
  }
  else
  {
    if ( commandIt->second.errorCodes.empty() )
    {
      return generateRAIIHandleCommandResultMultiSuccessNoErrors( commandIt, initialSkipCount, definition );
    }
    else
    {
      return generateRAIIHandleCommandResultMultiSuccessWithErrors( commandIt, initialSkipCount, definition );
    }
  }
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultMultiSuccessNoErrors( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                     size_t                                             initialSkipCount,
                                                                                     bool                                               definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandIt->second.params );
  switch ( returnParams.size() )
  {
    case 0:
      return generateRAIIHandleCommandEnhanced(
        commandIt, initialSkipCount, returnParams, determineVectorParams( commandIt->second.params ), definition, false, false );
    case 2: return generateRAIIHandleCommandResultMultiSuccessNoErrors2Return( commandIt, initialSkipCount, definition, returnParams );
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultMultiSuccessNoErrors2Return( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                            size_t                                             initialSkipCount,
                                                                                            bool                                               definition,
                                                                                            std::vector<size_t> const & returnParams ) const
{
  if ( ( commandIt->second.successCodes.size() == 2 ) && ( commandIt->second.successCodes[0] == "VK_SUCCESS" ) &&
       ( commandIt->second.successCodes[1] == "VK_INCOMPLETE" ) )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
    if ( vectorParams.size() == 1 )
    {
      if ( returnParams[0] == vectorParams.begin()->second.lenParam )
      {
        if ( returnParams[1] == vectorParams.begin()->first )
        {
          if ( ( commandIt->second.params[returnParams[0]].type.type == "uint32_t" ) || ( commandIt->second.params[returnParams[0]].type.type == "size_t" ) )
          {
            if ( ( commandIt->second.params[returnParams[1]].type.type != "void" ) && !isHandleType( commandIt->second.params[returnParams[1]].type.type ) &&
                 !isStructureChainAnchor( commandIt->second.params[returnParams[1]].type.type ) )
            {
              return generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
            }
          }
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultMultiSuccessWithErrors( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                       size_t                                             initialSkipCount,
                                                                                       bool                                               definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandIt->second.params );
  switch ( returnParams.size() )
  {
    case 0:
      return generateRAIIHandleCommandEnhanced(
        commandIt, initialSkipCount, returnParams, determineVectorParams( commandIt->second.params ), definition, false, false );
      break;
    case 1: return generateRAIIHandleCommandResultMultiSuccessWithErrors1Return( commandIt, initialSkipCount, definition, returnParams[0] ); break;
    case 2: return generateRAIIHandleCommandResultMultiSuccessWithErrors2Return( commandIt, initialSkipCount, definition, returnParams ); break;
    case 3: return generateRAIIHandleCommandResultMultiSuccessWithErrors3Return( commandIt, initialSkipCount, definition, returnParams ); break;
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultMultiSuccessWithErrors1Return( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                              size_t initialSkipCount,
                                                                                              bool   definition,
                                                                                              size_t returnParam ) const
{
  std::string str;
  if ( commandIt->second.params[returnParam].type.type == "void" )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
    if ( vectorParams.size() == 1 )
    {
      if ( returnParam == vectorParams.begin()->first )
      {
        if ( commandIt->second.params[vectorParams.begin()->second.lenParam].type.type == "size_t" )
        {
          str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, false );
          str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, true );
        }
      }
    }
  }
  else if ( isHandleType( commandIt->second.params[returnParam].type.type ) )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
    if ( vectorParams.size() == 2 )
    {
      if ( returnParam == std::next( vectorParams.begin() )->first )
      {
        if ( commandIt->second.params[vectorParams.begin()->second.lenParam].type.type == "uint32_t" )
        {
          if ( isStructureChainAnchor( commandIt->second.params[vectorParams.begin()->first].type.type ) )
          {
            str = generateRAIIHandleCommandFactory( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false );
            str += generateRAIIHandleCommandFactory( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, true );
          }
        }
      }
    }
  }
  else if ( !isStructureChainAnchor( commandIt->second.params[returnParam].type.type ) )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
    if ( vectorParams.empty() )
    {
      str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, false );
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultMultiSuccessWithErrors2Return( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                              size_t                      initialSkipCount,
                                                                                              bool                        definition,
                                                                                              std::vector<size_t> const & returnParams ) const
{
  if ( ( commandIt->second.successCodes.size() == 2 ) && ( commandIt->second.successCodes[0] == "VK_SUCCESS" ) &&
       ( commandIt->second.successCodes[1] == "VK_INCOMPLETE" ) )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
    switch ( vectorParams.size() )
    {
      case 0:
        if ( ( commandIt->second.params[returnParams[0]].type.type != "void" ) && !isHandleType( commandIt->second.params[returnParams[0]].type.type ) &&
             !isStructureChainAnchor( commandIt->second.params[returnParams[0]].type.type ) )
        {
          if ( ( commandIt->second.params[returnParams[1]].type.type != "void" ) && !isHandleType( commandIt->second.params[returnParams[1]].type.type ) &&
               !isStructureChainAnchor( commandIt->second.params[returnParams[1]].type.type ) )
          {
            return generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
          }
        }
        break;
      case 1:
        if ( returnParams[0] == vectorParams.begin()->second.lenParam )
        {
          if ( returnParams[1] == vectorParams.begin()->first )
          {
            if ( ( commandIt->second.params[returnParams[0]].type.type == "uint32_t" ) || ( commandIt->second.params[returnParams[0]].type.type == "size_t" ) )
            {
              // needs some very special handling of "vkGetSwapchainImagesKHR" !!
              if ( isHandleType( commandIt->second.params[returnParams[1]].type.type ) && ( commandIt->first != "vkGetSwapchainImagesKHR" ) )
              {
                return generateRAIIHandleCommandFactory( commandIt, initialSkipCount, returnParams, vectorParams, definition, false );
              }
              else
              {
                std::string str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
                if ( isStructureChainAnchor( commandIt->second.params[returnParams[1]].type.type ) )
                {
                  str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, true, false );
                }
                return str;
              }
            }
          }
        }
        break;
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultMultiSuccessWithErrors3Return( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                              size_t                      initialSkipCount,
                                                                                              bool                        definition,
                                                                                              std::vector<size_t> const & returnParams ) const
{
  if ( commandIt->second.params[returnParams[0]].type.type == "uint32_t" )
  {
    if ( ( commandIt->second.params[returnParams[1]].type.type != "void" ) && !isHandleType( commandIt->second.params[returnParams[1]].type.type ) &&
         !isStructureChainAnchor( commandIt->second.params[returnParams[1]].type.type ) )
    {
      if ( ( commandIt->second.params[returnParams[2]].type.type != "void" ) && !isHandleType( commandIt->second.params[returnParams[2]].type.type ) &&
           !isStructureChainAnchor( commandIt->second.params[returnParams[2]].type.type ) )
      {
        std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
        if ( vectorParams.size() == 2 )
        {
          if ( returnParams[0] == vectorParams.begin()->second.lenParam )
          {
            if ( returnParams[1] == vectorParams.begin()->first )
            {
              if ( returnParams[2] == std::next( vectorParams.begin() )->first )
              {
                if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
                {
                  if ( ( commandIt->second.successCodes.size() == 2 ) && ( commandIt->second.successCodes[0] == "VK_SUCCESS" ) &&
                       ( commandIt->second.successCodes[1] == "VK_INCOMPLETE" ) )
                  {
                    return generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
                  }
                }
              }
            }
          }
        }
      }
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultSingleSuccessNoErrors( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                      size_t                                             initialSkipCount,
                                                                                      bool                                               definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandIt->second.params );
  if ( returnParams.size() < 2 )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
    return generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultSingleSuccessWithErrors( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                        size_t                                             initialSkipCount,
                                                                                        bool                                               definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandIt->second.params );
  switch ( returnParams.size() )
  {
    case 0:
      return generateRAIIHandleCommandEnhanced(
        commandIt, initialSkipCount, returnParams, determineVectorParams( commandIt->second.params ), definition, false, false );
      break;
    case 1: return generateRAIIHandleCommandResultSingleSuccessWithErrors1Return( commandIt, initialSkipCount, definition, returnParams[0] ); break;
    case 2: return generateRAIIHandleCommandResultSingleSuccessWithErrors2Return( commandIt, initialSkipCount, definition, returnParams ); break;
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultSingleSuccessWithErrors1Return( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                               size_t initialSkipCount,
                                                                                               bool   definition,
                                                                                               size_t returnParam ) const
{
  std::string                       str;
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
  if ( commandIt->second.params[returnParam].type.type == "void" )
  {
    switch ( vectorParams.size() )
    {
      case 0: str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, false ); break;
      case 1:
        if ( returnParam == vectorParams.begin()->first )
        {
          if ( commandIt->second.params[vectorParams.begin()->second.lenParam].type.type == "size_t" )
          {
            str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, false );
            str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, true );
          }
        }
        break;
      case 2:
        if ( returnParam == std::next( vectorParams.begin() )->first )
        {
          if ( commandIt->second.params[vectorParams.begin()->second.lenParam].type.type == "uint32_t" )
          {
            if ( isHandleType( commandIt->second.params[vectorParams.begin()->first].type.type ) )
            {
              if ( commandIt->second.params[std::next( vectorParams.begin() )->second.lenParam].type.type == "size_t" )
              {
                str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, false );
                str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, true );
              }
            }
          }
        }
        break;
    }
  }
  else if ( isHandleType( commandIt->second.params[returnParam].type.type ) )
  {
    switch ( vectorParams.size() )
    {
      case 0: str = generateRAIIHandleCommandFactory( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false ); break;
      case 1:
        if ( returnParam == vectorParams.begin()->first )
        {
          if ( m_structures.find( commandIt->second.params[vectorParams.begin()->second.lenParam].type.type ) != m_structures.end() )
          {
            str = generateRAIIHandleCommandFactory( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false );
          }
        }
        break;
      case 2:
        if ( returnParam == std::next( vectorParams.begin() )->first )
        {
          if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
          {
            if ( commandIt->second.params[vectorParams.begin()->second.lenParam].type.type == "uint32_t" )
            {
              if ( isStructureChainAnchor( commandIt->second.params[vectorParams.begin()->first].type.type ) )
              {
                str = generateRAIIHandleCommandFactory( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false );
                str += generateRAIIHandleCommandFactory( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, true );
              }
            }
          }
        }
        break;
    }
  }
  else if ( isStructureChainAnchor( commandIt->second.params[returnParam].type.type ) )
  {
    if ( vectorParams.empty() )
    {
      str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, false );
      str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, true, false );
    }
  }
  else if ( vectorParams.empty() )
  {
    str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, { returnParam }, vectorParams, definition, false, false );
  }
  return str;
}

std::string VulkanHppGenerator::generateRAIIHandleCommandResultSingleSuccessWithErrors2Return( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                                               size_t                      initialSkipCount,
                                                                                               bool                        definition,
                                                                                               std::vector<size_t> const & returnParams ) const
{
  std::string str;
  if ( commandIt->second.params[returnParams[0]].type.type == "uint64_t" )
  {
    if ( commandIt->second.params[returnParams[1]].type.type == "uint64_t" )
    {
      std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
      if ( vectorParams.size() == 2 )
      {
        if ( returnParams[0] == std::next( vectorParams.begin() )->first )
        {
          assert( returnParams[1] != std::next( vectorParams.begin() )->second.lenParam );
          if ( returnParams[1] != vectorParams.begin()->first )
          {
            assert( returnParams[1] != vectorParams.begin()->second.lenParam );
            if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
            {
              if ( commandIt->second.params[vectorParams.begin()->second.lenParam].type.type == "uint32_t" )
              {
                if ( ( commandIt->second.params[vectorParams.begin()->first].type.type != "void" ) &&
                     !isHandleType( commandIt->second.params[vectorParams.begin()->first].type.type ) &&
                     !isStructureChainAnchor( commandIt->second.params[vectorParams.begin()->first].type.type ) )
                {
                  // two returns and two vectors! But one input vector, one output vector of the same size,
                  // and one output value
                  str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
                  str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, true );
                }
              }
            }
          }
        }
      }
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateRAIIHandleCommandValue( std::map<std::string, CommandData>::const_iterator commandIt,
                                                                size_t                                             initialSkipCount,
                                                                bool                                               definition ) const
{
  std::vector<size_t> returnParams = determineReturnParams( commandIt->second.params );
  if ( returnParams.empty() )
  {
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
    if ( vectorParams.empty() )
    {
      return generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
    }
  }
  return "";
}

std::string VulkanHppGenerator::generateRAIIHandleCommandVoid( std::map<std::string, CommandData>::const_iterator commandIt,
                                                               size_t                                             initialSkipCount,
                                                               bool                                               definition ) const
{
  std::string                       str;
  std::vector<size_t>               returnParams = determineReturnParams( commandIt->second.params );
  std::map<size_t, VectorParamData> vectorParams = determineVectorParams( commandIt->second.params );
  switch ( returnParams.size() )
  {
    case 0: str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false ); break;
    case 1:
      if ( commandIt->second.params[returnParams[0]].type.postfix == "**" )
      {
        // get a pointer to something
        if ( commandIt->second.params[returnParams[0]].type.type == "void" )
        {
          if ( vectorParams.empty() )
          {
            str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
          }
        }
      }
      else if ( isHandleType( commandIt->second.params[returnParams[0]].type.type ) )
      {
        if ( vectorParams.empty() )
        {
          str = generateRAIIHandleCommandFactory( commandIt, initialSkipCount, returnParams, vectorParams, definition, false );
        }
      }
      else if ( commandIt->second.params[returnParams[0]].type.type == "void" )
      {
        if ( vectorParams.empty() )
        {
          str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
        }
      }
      else
      {
        auto returnVectorParamIt = vectorParams.find( returnParams[0] );
        if ( returnVectorParamIt == vectorParams.end() )
        {
          str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
          if ( isStructureChainAnchor( commandIt->second.params[returnParams[0]].type.type ) )
          {
            str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, true, false );
          }
        }
      }
      break;
    case 2:
      if ( commandIt->second.params[returnParams[0]].type.type == "uint32_t" )
      {
        if ( vectorParams.size() == 1 )
        {
          if ( returnParams[0] == vectorParams.begin()->second.lenParam )
          {
            if ( returnParams[1] == vectorParams.begin()->first )
            {
              str = generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, false, false );
              if ( isStructureChainAnchor( commandIt->second.params[returnParams[1]].type.type ) )
              {
                str += generateRAIIHandleCommandEnhanced( commandIt, initialSkipCount, returnParams, vectorParams, definition, true, false );
              }
            }
          }
        }
      }
      break;
  }
  return str;
}

std::pair<std::string, std::string>
  VulkanHppGenerator::generateRAIIHandleConstructor( std::pair<std::string, HandleData> const &                             handle,
                                                     std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                     std::string const &                                                    enter,
                                                     std::string const &                                                    leave ) const
{
  std::string singularConstructor, arrayConstructor;
  if ( constructorIt->second.returnType == "VkResult" )
  {
    std::tie( singularConstructor, arrayConstructor ) = generateRAIIHandleConstructorResult( handle, constructorIt, enter, leave );
  }
  else if ( constructorIt->second.returnType == "void" )
  {
    std::tie( singularConstructor, arrayConstructor ) = generateRAIIHandleConstructorVoid( handle, constructorIt, enter, leave );
  }
  if ( singularConstructor.empty() && arrayConstructor.empty() )
  {
    throw std::runtime_error( "Never encountered a function like <" + constructorIt->first + "> !" );
  }
  return std::make_pair( singularConstructor, arrayConstructor );
}

std::pair<std::string, std::string>
  VulkanHppGenerator::generateRAIIHandleConstructor1Return2Vector( std::pair<std::string, HandleData> const &         handle,
                                                                   std::map<std::string, CommandData>::const_iterator constructorIt,
                                                                   std::string const &                                enter,
                                                                   std::string const &                                leave,
                                                                   size_t                                             returnParam,
                                                                   std::map<size_t, VectorParamData> const &          vectorParams ) const
{
  if ( returnParam == std::next( vectorParams.begin() )->first )
  {
    if ( vectorParams.begin()->second.lenParam == std::next( vectorParams.begin() )->second.lenParam )
    {
      if ( constructorIt->second.params[vectorParams.begin()->second.lenParam].type.type == "uint32_t" )
      {
        if ( isStructureChainAnchor( constructorIt->second.params[vectorParams.begin()->first].type.type ) )
        {
          std::string singularConstructor;
          auto        lenParamIt    = constructorIt->second.params.begin() + vectorParams.begin()->second.lenParam;
          auto        handleParamIt = constructorIt->second.params.begin() + std::next( vectorParams.begin() )->first;
          if ( !checkEquivalentSingularConstructor( handle.second.constructorIts, constructorIt, lenParamIt ) )
          {
            singularConstructor = generateRAIIHandleConstructorVectorSingular( handle, constructorIt, handleParamIt, enter, leave );
          }
          return std::make_pair( singularConstructor, generateRAIIHandleConstructorVector( handle, constructorIt, handleParamIt, enter, leave ) );
        }
      }
    }
  }
  return std::make_pair( "", "" );
}

std::pair<std::string, std::string> VulkanHppGenerator::generateRAIIHandleConstructors( std::pair<std::string, HandleData> const & handle ) const
{
  auto [enter, leave] = generateProtection( handle.first, !handle.second.alias.empty() );

  std::string singularConstructors, arrayConstructors;
  for ( auto constructorIt : handle.second.constructorIts )
  {
    // there is a non-const parameter with handle type : the to-be-constructed handle

    // check for additional enter/leave guards for the constructors
    auto [constructorEnter, constructorLeave] = generateProtection( constructorIt->second.referencedIn, std::string() );
    if ( constructorEnter == enter )
    {
      constructorEnter.clear();
      constructorLeave.clear();
    }

    auto [singularConstructor, arrayConstructor] = generateRAIIHandleConstructor( handle, constructorIt, constructorEnter, constructorLeave );
    arrayConstructors += arrayConstructor;
    singularConstructors += singularConstructor;
  }
  singularConstructors += generateRAIIHandleConstructorTakeOwnership( handle );
  return std::make_pair( singularConstructors, arrayConstructors );
}

std::string VulkanHppGenerator::generateRAIIHandleConstructorArgument( ParamData const & param, bool definition, bool singular, bool takesOwnership ) const
{
  std::string argument;
  if ( param.type.isConstPointer() )
  {
    assert( param.type.type.starts_with( "Vk" ) );
    assert( param.name.starts_with( "p" ) );
    std::string argumentName = startLowerCase( stripPrefix( param.name, "p" ) );
    std::string argumentType = generateNamespacedType( param.type.type );
    if ( param.optional )
    {
      assert( param.len.empty() );
      argument = "VULKAN_HPP_NAMESPACE::Optional<const " + argumentType + "> " + argumentName + ( definition ? "" : " = nullptr" );
    }
    else if ( param.len.empty() )
    {
      argument = argumentType + " const & " + argumentName;
    }
    else if ( singular )
    {
      argument = argumentType + " const & " + stripPluralS( argumentName );
    }
    else
    {
      argument = "VULKAN_HPP_NAMESPACE::ArrayProxy<" + argumentType + "> const & " + argumentName;
    }
  }
  else if ( specialPointerTypes.find( param.type.type ) != specialPointerTypes.end() )
  {
    assert( !param.optional );
    assert( param.type.isNonConstPointer() );
    argument = param.type.type + " & " + param.name;
  }
  else if ( ( param.type.isValue() ) && isHandleType( param.type.type ) )
  {
    if ( takesOwnership )
    {
      assert( !param.optional );
      argument = param.type.type + " " + param.name;
    }
    else
    {
      argument = "VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::" + stripPrefix( param.type.type, "Vk" );
      if ( param.optional )
      {
        argument = "VULKAN_HPP_NAMESPACE::Optional<const " + argument + ">";
      }
      argument += " const & " + param.name;
    }
  }
  else
  {
    assert( !param.optional );
    argument = param.type.compose( "VULKAN_HPP_NAMESPACE" ) + " " + param.name;
  }
  return argument;
}

std::string VulkanHppGenerator::generateRAIIHandleConstructorArguments( std::pair<std::string, HandleData> const &                             handle,
                                                                        std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                                        bool                                                                   singular,
                                                                        bool takesOwnership ) const
{
  auto [parentType, parentName] = getParentTypeAndName( handle );

  std::string arguments = "VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::" + parentType + " const & " + parentName;
  if ( takesOwnership )
  {
    arguments += ", " + handle.first + " " + generateRAIIHandleConstructorParamName( handle.first, handle.second.destructorIt );
  }

  if ( constructorIt != m_commands.end() )
  {
    parentType = "Vk" + parentType;
    bool skip  = skipLeadingGrandParent( handle );
    for ( size_t i = skip ? 1 : 0; i < constructorIt->second.params.size(); i++ )
    {
      ParamData const & param = constructorIt->second.params[i];
      // filter parent and handle type
      if ( ( param.type.type != parentType ) && ( param.type.type != handle.first ) )
      {
        // the specialPointerTypes are considered const-pointers!
        if ( param.type.isNonConstPointer() && ( specialPointerTypes.find( param.type.type ) == specialPointerTypes.end() ) )
        {
          // this is supposed to be the returned size on an enumeration function!
#if !defined( NDEBUG )
          assert( param.type.type == "uint32_t" );
          auto typeIt = std::find_if( constructorIt->second.params.begin(),
                                      constructorIt->second.params.end(),
                                      [&handle]( ParamData const & pd ) { return pd.type.type == handle.first; } );
          assert( typeIt != constructorIt->second.params.end() );
          assert( typeIt->len == param.name );
#endif
          continue;
        }
        else if ( std::find_if( constructorIt->second.params.begin(),
                                constructorIt->second.params.end(),
                                [&param]( ParamData const & pd ) { return pd.len == param.name; } ) != constructorIt->second.params.end() )
        {
          // this is the len of an other parameter, which will be mapped to an ArrayProxy
          assert( param.type.isValue() && ( param.type.type == "uint32_t" ) );
          assert( param.arraySizes.empty() && param.len.empty() && !param.optional );
          continue;
        }
        arguments += ", " + generateRAIIHandleConstructorArgument( param, false, singular, takesOwnership );
      }
    }
  }
  return arguments;
}

std::string
  VulkanHppGenerator::generateRAIIHandleConstructorCallArguments( std::pair<std::string, HandleData> const &                             handle,
                                                                  std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                                  bool                     nonConstPointerAsNullptr,
                                                                  std::set<size_t> const & singularParams,
                                                                  bool                     allocatorIsMemberVariable ) const
{
  std::string arguments;
  bool        encounteredArgument = false;
  size_t      i                   = 0;
  if ( skipLeadingGrandParent( handle ) )
  {
    assert( ( 1 < constructorIt->second.params.size() ) && ( m_handles.find( constructorIt->second.params[0].type.type ) != m_handles.end() ) &&
            ( m_handles.find( constructorIt->second.params[1].type.type ) != m_handles.end() ) );
    arguments += "static_cast<" + constructorIt->second.params[0].type.type + ">( " + constructorIt->second.params[1].name + ".get" +
                 stripPrefix( constructorIt->second.params[0].type.type, "Vk" ) + "() )";
    encounteredArgument = true;
    i                   = 1;
  }
  for ( ; i < constructorIt->second.params.size(); ++i )
  {
    ParamData const & param = constructorIt->second.params[i];
    if ( encounteredArgument )
    {
      arguments += ", ";
    }
    if ( param.type.type == handle.first )
    {
      assert( param.type.isNonConstPointer() && param.arraySizes.empty() );
      if ( param.len.empty() || !singularParams.empty() )
      {
        assert( !param.optional );
        assert( singularParams.empty() || ( param.len == constructorIt->second.params[*singularParams.begin()].name ) );
        std::string paramName = generateRAIIHandleConstructorParamName( handle.first, handle.second.destructorIt );
        arguments += "reinterpret_cast<" + handle.first + "*>( &m_" + paramName + " )";
      }
      else if ( nonConstPointerAsNullptr )
      {
        arguments += "nullptr";
      }
      else
      {
        arguments += startLowerCase( stripPrefix( param.name, "p" ) ) + ".data()";
      }
    }
    else if ( param.type.type == "VkAllocationCallbacks" )
    {
      assert( param.optional );
      if ( allocatorIsMemberVariable )
      {
        arguments += "reinterpret_cast<const VkAllocationCallbacks *>( m_allocator )";
      }
      else
      {
        arguments += "reinterpret_cast<const VkAllocationCallbacks *>(static_cast<const VULKAN_HPP_NAMESPACE::AllocationCallbacks *>( allocator ) )";
      }
    }
    else if ( m_handles.find( param.type.type ) != m_handles.end() )
    {
      assert( param.type.isValue() && param.arraySizes.empty() && param.len.empty() );
      if ( param.optional )
      {
        arguments += param.name + " ? static_cast<" + param.type.type + ">( **" + param.name + " ) : 0";
      }
      else
      {
        arguments += "static_cast<" + param.type.type + ">( *" + param.name + " )";
      }
    }
    else
    {
      assert( !param.optional );
      arguments += generateCallArgumentEnhanced( constructorIt->second.params, i, nonConstPointerAsNullptr, singularParams, {} );
    }
    encounteredArgument = true;
  }
  return arguments;
}

std::string VulkanHppGenerator::generateRAIIHandleConstructorEnumerate( std::pair<std::string, HandleData> const &                             handle,
                                                                        std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                                        std::vector<ParamData>::const_iterator                                 handleParamIt,
                                                                        std::vector<ParamData>::const_iterator                                 lenParamIt,
                                                                        std::string const &                                                    enter,
                                                                        std::string const &                                                    leave ) const
{
  std::string handleConstructorArguments = generateRAIIHandleSingularConstructorArguments( handle, constructorIt );
  std::string handleType                 = stripPrefix( handle.first, "Vk" );
  std::string dispatcherType             = hasParentHandle( handle.first, "VkDevice" ) ? "VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::DeviceDispatcher"
                                                                                       : "VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::InstanceDispatcher";

  const std::string constructorTemplate =
    R"(
${enter}    ${handleType}s( ${constructorArguments} )
    {
      ${dispatcherType} const * dispatcher = ${parentName}.getDispatcher();
      std::vector<${vectorElementType}> ${vectorName};
      ${counterType} ${counterName};
      VULKAN_HPP_NAMESPACE::Result result;
      do
      {
        result = static_cast<VULKAN_HPP_NAMESPACE::Result>( dispatcher->${constructorCall}( ${firstCallArguments} ) );
        if ( ( result == VULKAN_HPP_NAMESPACE::Result::eSuccess ) && ${counterName} )
        {
          ${vectorName}.resize( ${counterName} );
          result = static_cast<VULKAN_HPP_NAMESPACE::Result>( dispatcher->${constructorCall}( ${secondCallArguments} ) );
        }
      } while ( result == VULKAN_HPP_NAMESPACE::Result::eIncomplete );
      if ( result == VULKAN_HPP_NAMESPACE::Result::eSuccess )
      {
        VULKAN_HPP_ASSERT( ${counterName} <= ${vectorName}.size() );
        this->reserve( ${counterName} );
        for ( auto const & ${handleName} : ${vectorName} )
        {
          this->emplace_back( ${parentName}, ${handleConstructorArguments} );
        }
      }
      else
      {
        throwResultException( result, "${constructorCall}" );
      }
    }
${leave})";

  return replaceWithMap( constructorTemplate,
                         { { "constructorArguments", generateRAIIHandleConstructorArguments( handle, constructorIt, false, false ) },
                           { "constructorCall", constructorIt->first },
                           { "counterName", startLowerCase( stripPrefix( lenParamIt->name, "p" ) ) },
                           { "counterType", lenParamIt->type.type },
                           { "dispatcherType", dispatcherType },
                           { "enter", enter },
                           { "firstCallArguments", generateRAIIHandleConstructorCallArguments( handle, constructorIt, true, {}, true ) },
                           { "handleConstructorArguments", handleConstructorArguments },
                           { "handleName", startLowerCase( handleType ) },
                           { "handleType", handleType },
                           { "leave", leave },
                           { "parentName", constructorIt->second.params.front().name },
                           { "secondCallArguments", generateRAIIHandleConstructorCallArguments( handle, constructorIt, false, {}, true ) },
                           { "vectorElementType", handleParamIt->type.type },
                           { "vectorName", startLowerCase( stripPrefix( handleParamIt->name, "p" ) ) } } );
}

std::string
  VulkanHppGenerator::generateRAIIHandleConstructorInitializationList( std::pair<std::string, HandleData> const &                             handle,
                                                                       std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                                       std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator destructorIt,
                                                                       bool takesOwnership ) const
{
  auto [parentType, parentName] = getParentTypeAndName( handle );
  std::string handleName        = generateRAIIHandleConstructorParamName( handle.first, destructorIt );

  std::string initializationList;
  if ( destructorIt != m_commands.end() )
  {
    for ( auto destructorParam : destructorIt->second.params )
    {
      if ( destructorParam.type.type == "Vk" + parentType )
      {
        initializationList += "m_" + parentName + "( *" + parentName + " ), ";
      }
      else if ( destructorParam.type.type == handle.first )
      {
        if ( takesOwnership )
        {
          initializationList += "m_" + handleName + "( " + handleName + " ), ";
        }
      }
      else if ( destructorParam.type.type == "VkAllocationCallbacks" )
      {
        assert( destructorParam.type.isConstPointer() && destructorParam.arraySizes.empty() && destructorParam.len.empty() && destructorParam.optional );
        initializationList += "m_allocator( static_cast<const VULKAN_HPP_NAMESPACE::AllocationCallbacks *>( allocator ) ), ";
      }
      else if ( isHandleType( destructorParam.type.type ) )
      {
        assert( destructorParam.type.isValue() && destructorParam.arraySizes.empty() && destructorParam.len.empty() && !destructorParam.optional );
        initializationList += "m_" + destructorParam.name + "( ";
        auto constructorParamIt = std::find_if( constructorIt->second.params.begin(),
                                                constructorIt->second.params.end(),
                                                [&destructorParam]( ParamData const & pd ) { return pd.type.type == destructorParam.type.type; } );
        if ( constructorParamIt != constructorIt->second.params.end() )
        {
          assert( constructorParamIt->type.isValue() && constructorParamIt->arraySizes.empty() && constructorParamIt->len.empty() &&
                  !constructorParamIt->optional );
          if ( constructorParamIt->type.type == "Vk" + parentType )
          {
            initializationList += "*";
          }
          initializationList += constructorParamIt->name;
        }
        else
        {
#if !defined( NDEBUG )
          bool found = false;
#endif
          for ( auto constructorParam : constructorIt->second.params )
          {
            auto structureIt = m_structures.find( constructorParam.type.type );
            if ( structureIt != m_structures.end() )
            {
              auto structureMemberIt = findStructMemberItByType( destructorParam.type.type, structureIt->second.members );
              if ( structureMemberIt != structureIt->second.members.end() )
              {
                assert( constructorParam.type.isConstPointer() && constructorParam.arraySizes.empty() && constructorParam.len.empty() &&
                        !constructorParam.optional );
                initializationList += startLowerCase( stripPrefix( constructorParam.name, "p" ) ) + "." + structureMemberIt->name;
#if !defined( NDEBUG )
                found = true;
#endif
                break;
              }
            }
          }
          assert( found );
        }
        initializationList += " ), ";
      }
      else
      {
        // we can ignore all other parameters here !
      }
    }
  }
  else
  {
    if ( !handle.second.secondLevelCommands.empty() )
    {
      assert( !handle.second.constructorIts.empty() );
#if !defined( NDEBUG )
      auto constructorCommandIt = m_commands.find( handle.second.constructorIts.front()->first );
#endif
      assert( ( constructorCommandIt != m_commands.end() ) && ( 1 < constructorCommandIt->second.params.size() ) );
      assert( std::next( constructorCommandIt->second.params.begin() )->type.type == "Vk" + parentType );

      auto commandIt = m_commands.find( *handle.second.secondLevelCommands.begin() );
      assert( ( commandIt != m_commands.end() ) && ( 1 < commandIt->second.params.size() ) );
      assert( commandIt->second.params.front().type.type == constructorCommandIt->second.params.front().type.type );
      assert( std::next( commandIt->second.params.begin() )->type.type == handle.first );

      std::string grandParentType = stripPrefix( commandIt->second.params.front().type.type, "Vk" );
      initializationList += "m_" + startLowerCase( grandParentType ) + "( " + parentName + ".get" + grandParentType + "() ), ";
    }
    if ( takesOwnership )
    {
      initializationList += "m_" + handleName + "( " + handleName + " ), ";
    }
  }
  return initializationList.empty() ? initializationList : initializationList.substr( 0, initializationList.size() - 2 );
}

std::string VulkanHppGenerator::generateRAIIHandleConstructorParamName( std::string const &                                type,
                                                                        std::map<std::string, CommandData>::const_iterator destructorIt ) const
{
  if ( destructorIt != m_commands.end() )
  {
    auto destructorParamIt = std::find_if( destructorIt->second.params.begin(),
                                           destructorIt->second.params.end(),
                                           [&type]( ParamData const & destructorParam ) { return destructorParam.type.type == type; } );
    if ( destructorParamIt != destructorIt->second.params.end() )
    {
      assert( std::find_if( std::next( destructorParamIt ),
                            destructorIt->second.params.end(),
                            [&type]( ParamData const & destructorParam ) { return destructorParam.type.type == type; } ) == destructorIt->second.params.end() );
      if ( !destructorParamIt->type.isValue() )
      {
        return startLowerCase( stripPrefix( stripPluralS( destructorParamIt->name ), "p" ) );
      }
      else
      {
        return destructorParamIt->name;
      }
    }
  }
  return startLowerCase( stripPrefix( type, "Vk" ) );
}

std::pair<std::string, std::string> VulkanHppGenerator::generateRAIIHandleConstructorResult( std::pair<std::string, HandleData> const &         handle,
                                                                                             std::map<std::string, CommandData>::const_iterator constructorIt,
                                                                                             std::string const &                                enter,
                                                                                             std::string const &                                leave ) const
{
  assert( !constructorIt->second.successCodes.empty() );
  assert( constructorIt->second.successCodes[0] == "VK_SUCCESS" );
  switch ( constructorIt->second.successCodes.size() )
  {
    case 1:
      if ( !constructorIt->second.errorCodes.empty() )
      {
        std::vector<size_t> returnParams = determineReturnParams( constructorIt->second.params );
        if ( returnParams.size() == 1 )
        {
          assert( isHandleType( constructorIt->second.params[returnParams[0]].type.type ) );
          std::map<size_t, VectorParamData> vectorParams = determineVectorParams( constructorIt->second.params );
          switch ( vectorParams.size() )
          {
            case 0:
              return std::make_pair( generateRAIIHandleConstructorResultSingleSuccessWithErrors1Return0Vector( handle, constructorIt, enter, leave ), "" );
            case 1:
              if ( returnParams[0] == vectorParams.begin()->first )
              {
                if ( isLenByStructMember( constructorIt->second.params[vectorParams.begin()->first].len,
                                          constructorIt->second.params[vectorParams.begin()->second.lenParam] ) )
                {
                  auto handleParamIt = constructorIt->second.params.begin() + returnParams[0];
                  return std::make_pair( "", generateRAIIHandleConstructorVector( handle, constructorIt, handleParamIt, enter, leave ) );
                }
              }
              break;
            case 2: return generateRAIIHandleConstructor1Return2Vector( handle, constructorIt, enter, leave, returnParams[0], vectorParams );
          }
        }
      }
      break;
    case 2:
      if ( !constructorIt->second.errorCodes.empty() )
      {
        std::vector<size_t> returnParams = determineReturnParams( constructorIt->second.params );
        switch ( returnParams.size() )
        {
          case 1:
            assert( isHandleType( constructorIt->second.params[returnParams[0]].type.type ) );
            {
              std::map<size_t, VectorParamData> vectorParams = determineVectorParams( constructorIt->second.params );
              if ( vectorParams.size() == 2 )
              {
                return generateRAIIHandleConstructor1Return2Vector( handle, constructorIt, enter, leave, returnParams[0], vectorParams );
              }
            }
            break;
          case 2:
            if ( constructorIt->second.params[returnParams[0]].type.type == "uint32_t" )
            {
              assert( isHandleType( constructorIt->second.params[returnParams[1]].type.type ) );
              std::map<size_t, VectorParamData> vectorParams = determineVectorParams( constructorIt->second.params );
              if ( vectorParams.size() == 1 )
              {
                if ( returnParams[0] == vectorParams.begin()->second.lenParam )
                {
                  assert( returnParams[1] == vectorParams.begin()->first );
                  assert( constructorIt->second.successCodes[1] == "VK_INCOMPLETE" );
                  auto lenParamIt    = constructorIt->second.params.begin() + returnParams[0];
                  auto handleParamIt = constructorIt->second.params.begin() + returnParams[1];
                  return std::make_pair( "", generateRAIIHandleConstructorEnumerate( handle, constructorIt, handleParamIt, lenParamIt, enter, leave ) );
                }
              }
            }
            break;
        }
      }
      break;
    case 4:
      if ( !constructorIt->second.errorCodes.empty() )
      {
        std::vector<size_t> returnParams = determineReturnParams( constructorIt->second.params );
        if ( returnParams.size() == 1 )
        {
          assert( isHandleType( constructorIt->second.params[returnParams[0]].type.type ) );
          std::map<size_t, VectorParamData> vectorParams = determineVectorParams( constructorIt->second.params );
          if ( vectorParams.size() == 2 )
          {
            return generateRAIIHandleConstructor1Return2Vector( handle, constructorIt, enter, leave, returnParams[0], vectorParams );
          }
        }
      }
      break;
  }
  return std::make_pair( "", "" );
}

std::string VulkanHppGenerator::generateRAIIHandleConstructorResultSingleSuccessWithErrors1Return0Vector(
  std::pair<std::string, HandleData> const &                             handle,
  std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
  std::string const &                                                    enter,
  std::string const &                                                    leave ) const
{
  auto [parentType, parentName] = getParentTypeAndName( handle );

  std::string getDispatcher = parentName + ".getDispatcher()";
  std::string dispatcherInitializer, dispatcherInit;
  if ( ( handle.first != "VkInstance" ) && ( handle.first != "VkDevice" ) )
  {
    dispatcherInitializer = "m_dispatcher( " + getDispatcher + " )";
  }
  else
  {
    std::string handleType = stripPrefix( handle.first, "Vk" );
    dispatcherInit         = "\n        m_dispatcher.reset( new VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::" + handleType + "Dispatcher( " + parentName +
                     ".getDispatcher()->vkGet" + handleType + "ProcAddr, static_cast<" + handle.first + ">( m_" + startLowerCase( handleType ) + " ) ) );";
  }

  std::string constructorArguments = generateRAIIHandleConstructorArguments( handle, constructorIt, false, false );

  std::string callArguments = generateRAIIHandleConstructorCallArguments( handle, constructorIt, false, {}, handle.second.destructorIt != m_commands.end() );

  std::string initializationList = generateRAIIHandleConstructorInitializationList( handle, constructorIt, handle.second.destructorIt, false );
  if ( !initializationList.empty() && !dispatcherInitializer.empty() )
  {
    initializationList += ", ";
  }

  const std::string constructorTemplate =
    R"(
${enter}    ${handleType}( ${constructorArguments} )
      : ${initializationList}${dispatcherInitializer}
    {
      VULKAN_HPP_NAMESPACE::Result result = static_cast<VULKAN_HPP_NAMESPACE::Result>( ${getDispatcher}->${constructorCall}( ${callArguments} ) );
      if ( ${failureCheck} )
      {
        throwResultException( result, "${constructorCall}" );
      }${dispatcherInit}
    }
${leave})";

  return replaceWithMap( constructorTemplate,
                         { { "callArguments", callArguments },
                           { "constructorArguments", constructorArguments },
                           { "constructorCall", constructorIt->first },
                           { "dispatcherInitializer", dispatcherInitializer },
                           { "dispatcherInit", dispatcherInit },
                           { "enter", enter },
                           { "failureCheck", generateFailureCheck( constructorIt->second.successCodes ) },
                           { "getDispatcher", getDispatcher },
                           { "leave", leave },
                           { "handleType", stripPrefix( handle.first, "Vk" ) },
                           { "initializationList", initializationList } } );
}

std::string VulkanHppGenerator::generateRAIIHandleConstructorTakeOwnership( std::pair<std::string, HandleData> const & handle ) const
{
  std::string handleType = stripPrefix( handle.first, "Vk" );
  std::string handleName = startLowerCase( handleType );

  auto [parentType, parentName] = getParentTypeAndName( handle );

  std::string constructorArguments = generateRAIIHandleConstructorArguments( handle, handle.second.destructorIt, false, true );
  std::string initializationList   = generateRAIIHandleConstructorInitializationList( handle, handle.second.destructorIt, handle.second.destructorIt, true );
  assert( !handle.second.constructorIts.empty() );
  if ( 1 < handle.second.constructorIts[0]->second.successCodes.size() && ( handle.second.constructorIts[0]->second.successCodes[1] != "VK_INCOMPLETE" ) )
  {
#if !defined( NDEBUG )
    for ( size_t i = 1; i < handle.second.constructorIts.size(); ++i )
    {
      assert( 1 < handle.second.constructorIts[i]->second.successCodes.size() );
    }
#endif
    constructorArguments += ", VULKAN_HPP_NAMESPACE::Result successCode = VULKAN_HPP_NAMESPACE::Result::eSuccess";
    initializationList += ", m_constructorSuccessCode( successCode )";
  }

  std::string dispatcherInitializer;
  if ( ( handle.first != "VkInstance" ) && ( handle.first != "VkDevice" ) )
  {
    dispatcherInitializer = "m_dispatcher( " + parentName + ".getDispatcher() )";
  }
  if ( !initializationList.empty() && !dispatcherInitializer.empty() )
  {
    initializationList += ", ";
  }

  std::string dispatcherInit;
  if ( ( handle.first == "VkDevice" ) || ( handle.first == "VkInstance" ) )
  {
    dispatcherInit = "\n        m_dispatcher.reset( new VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::" + handleType + "Dispatcher( " + parentName +
                     ".getDispatcher()->vkGet" + handleType + "ProcAddr, static_cast<" + handle.first + ">( m_" + startLowerCase( handleType ) + " ) ) );";
  }

  const std::string constructorTemplate =
    R"(
    ${handleType}( ${constructorArguments} )
      : ${initializationList}${dispatcherInitializer}
    {${dispatcherInit}}
)";

  return replaceWithMap( constructorTemplate,
                         { { "constructorArguments", constructorArguments },
                           { "dispatcherInitializer", dispatcherInitializer },
                           { "dispatcherInit", dispatcherInit },
                           { "handleType", handleType },
                           { "initializationList", initializationList } } );
}

std::string VulkanHppGenerator::generateRAIIHandleConstructorVector( std::pair<std::string, HandleData> const &                             handle,
                                                                     std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                                     std::vector<ParamData>::const_iterator                                 handleParamIt,
                                                                     std::string const &                                                    enter,
                                                                     std::string const &                                                    leave ) const
{
  std::string vectorSize;
  auto        lenIt = std::find_if( constructorIt->second.params.begin(),
                             constructorIt->second.params.end(),
                             [&handleParamIt]( ParamData const & pd ) { return pd.name == handleParamIt->len; } );
  if ( lenIt == constructorIt->second.params.end() )
  {
    std::vector<std::string> lenParts = tokenize( handleParamIt->len, "->" );
    assert( lenParts.size() == 2 );
    lenIt = std::find_if(
      constructorIt->second.params.begin(), constructorIt->second.params.end(), [&lenParts]( ParamData const & pd ) { return pd.name == lenParts[0]; } );
#if !defined( NDEBUG )
    assert( lenIt != constructorIt->second.params.end() );
    auto structureIt = m_structures.find( lenIt->type.type );
    assert( structureIt != m_structures.end() );
    assert( isStructMember( lenParts[1], structureIt->second.members ) );
    assert( constructorIt->second.successCodes.size() == 1 );
#endif
    vectorSize = startLowerCase( stripPrefix( lenParts[0], "p" ) ) + "." + lenParts[1];
  }
  else
  {
    auto arrayIt = std::find_if( constructorIt->second.params.begin(),
                                 constructorIt->second.params.end(),
                                 [&lenIt, &handleParamIt]( ParamData const & pd ) { return ( pd.len == lenIt->name ) && ( pd.name != handleParamIt->name ); } );
    assert( arrayIt != constructorIt->second.params.end() );
    vectorSize = startLowerCase( stripPrefix( arrayIt->name, "p" ) ) + ".size()";
  }

  std::string handleConstructorArguments = generateRAIIHandleSingularConstructorArguments( handle, constructorIt );
  std::string handleType                 = stripPrefix( handle.first, "Vk" );
  std::string successCodePassToElement   = ( 1 < constructorIt->second.successCodes.size() ) ? ", result" : "";

  const std::string constructorTemplate =
    R"(
${enter}    ${handleType}s( ${constructorArguments} )
    {
      VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::DeviceDispatcher const * dispatcher = ${parentName}.getDispatcher();
      std::vector<${vectorElementType}> ${vectorName}( ${vectorSize} );
      VULKAN_HPP_NAMESPACE::Result result = static_cast<VULKAN_HPP_NAMESPACE::Result>( dispatcher->${constructorCall}( ${callArguments} ) );
      if ( ${successCheck} )
      {
        this->reserve( ${vectorSize} );
        for ( auto const & ${handleName} : ${vectorName} )
        {
          this->emplace_back( ${parentName}, ${handleConstructorArguments}${successCodePassToElement} );
        }
      }
      else
      {
        throwResultException( result, "${constructorCall}" );
      }
    }
${leave})";

  return replaceWithMap( constructorTemplate,
                         { { "callArguments", generateRAIIHandleConstructorCallArguments( handle, constructorIt, false, {}, false ) },
                           { "constructorArguments", generateRAIIHandleConstructorArguments( handle, constructorIt, false, false ) },
                           { "constructorCall", constructorIt->first },
                           { "enter", enter },
                           { "handleConstructorArguments", handleConstructorArguments },
                           { "handleName", startLowerCase( handleType ) },
                           { "handleType", handleType },
                           { "leave", leave },
                           { "parentName", constructorIt->second.params.front().name },
                           { "successCheck", generateSuccessCheck( constructorIt->second.successCodes ) },
                           { "successCodePassToElement", successCodePassToElement },
                           { "vectorElementType", handleParamIt->type.type },
                           { "vectorName", startLowerCase( stripPrefix( handleParamIt->name, "p" ) ) },
                           { "vectorSize", vectorSize } } );
}

std::string
  VulkanHppGenerator::generateRAIIHandleConstructorVectorSingular( std::pair<std::string, HandleData> const &                             handle,
                                                                   std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                                   std::vector<ParamData>::const_iterator                                 handleParamIt,
                                                                   std::string const &                                                    enter,
                                                                   std::string const &                                                    leave ) const
{
  size_t                            returnParam    = static_cast<size_t>( std::distance( constructorIt->second.params.begin(), handleParamIt ) );
  std::map<size_t, VectorParamData> vectorParams   = determineVectorParams( constructorIt->second.params );
  std::set<size_t>                  singularParams = determineSingularParams( returnParam, vectorParams );

  std::string callArguments      = generateRAIIHandleConstructorCallArguments( handle, constructorIt, false, singularParams, true );
  std::string initializationList = generateRAIIHandleConstructorInitializationList( handle, constructorIt, handle.second.destructorIt, false );
  assert( !initializationList.empty() );
  std::string failureCheck = generateFailureCheck( constructorIt->second.successCodes );
  failureCheck             = std::regex_replace( failureCheck, std::regex( "result" ), "m_constructorSuccessCode" );

  const std::string singularConstructorTemplate =
    R"(
${enter}    ${handleType}( ${constructorArguments} )
      : ${initializationList}, m_dispatcher( ${firstArgument}.getDispatcher() )
    {
      m_constructorSuccessCode = static_cast<VULKAN_HPP_NAMESPACE::Result>( getDispatcher()->${constructorCall}( ${callArguments} ) );
      if ( ${failureCheck} )
      {
        throwResultException( m_constructorSuccessCode, "${constructorCall}" );
      }
    }
${leave})";

  return replaceWithMap( singularConstructorTemplate,
                         { { "initializationList", initializationList },
                           { "callArguments", callArguments },
                           { "constructorArguments", generateRAIIHandleConstructorArguments( handle, constructorIt, true, false ) },
                           { "constructorCall", constructorIt->first },
                           { "enter", enter },
                           { "firstArgument", constructorIt->second.params[0].name },
                           { "failureCheck", failureCheck },
                           { "leave", leave },
                           { "handleType", stripPrefix( handle.first, "Vk" ) } } );
}

std::pair<std::string, std::string> VulkanHppGenerator::generateRAIIHandleConstructorVoid( std::pair<std::string, HandleData> const &         handle,
                                                                                           std::map<std::string, CommandData>::const_iterator constructorIt,
                                                                                           std::string const &                                enter,
                                                                                           std::string const &                                leave ) const
{
  assert( constructorIt->second.successCodes.empty() && constructorIt->second.errorCodes.empty() );
  std::vector<size_t> returnParams = determineReturnParams( constructorIt->second.params );
  if ( returnParams.size() == 1 )
  {
    assert( isHandleType( constructorIt->second.params[returnParams[0]].type.type ) );
    std::map<size_t, VectorParamData> vectorParams = determineVectorParams( constructorIt->second.params );
    if ( vectorParams.empty() )
    {
      return std::make_pair( generateRAIIHandleConstructorVoid1Return0Vector( handle, constructorIt, enter, leave ), "" );
    }
  }
  return std::make_pair( "", "" );
}

std::string
  VulkanHppGenerator::generateRAIIHandleConstructorVoid1Return0Vector( std::pair<std::string, HandleData> const &                             handle,
                                                                       std::map<std::string, VulkanHppGenerator::CommandData>::const_iterator constructorIt,
                                                                       std::string const &                                                    enter,
                                                                       std::string const &                                                    leave ) const
{
  std::string callArguments        = generateRAIIHandleConstructorCallArguments( handle, constructorIt, false, {}, true );
  std::string constructorArguments = generateRAIIHandleConstructorArguments( handle, constructorIt, false, false );
  std::string initializationList   = generateRAIIHandleConstructorInitializationList( handle, constructorIt, handle.second.destructorIt, false );
  if ( !initializationList.empty() )
  {
    initializationList += ", ";
  }

  const std::string constructorTemplate =
    R"(
${enter}    ${handleType}( ${constructorArguments} )
      : ${initializationList}m_dispatcher( ${firstArgument}.getDispatcher() )
    {
      getDispatcher()->${constructorCall}( ${callArguments} );
    }
${leave})";

  return replaceWithMap( constructorTemplate,
                         { { "callArguments", callArguments },
                           { "constructorArguments", constructorArguments },
                           { "constructorCall", constructorIt->first },
                           { "enter", enter },
                           { "firstArgument", constructorIt->second.params[0].name },
                           { "leave", leave },
                           { "handleType", stripPrefix( handle.first, "Vk" ) },
                           { "initializationList", initializationList } } );
}

std::string VulkanHppGenerator::generateRAIIHandleContext( std::pair<std::string, HandleData> const & handle,
                                                           std::set<std::string> const &              specialFunctions ) const
{
  const std::string contextTemplate = R"(
    class Context
    {
    public:
#if VULKAN_HPP_ENABLE_DYNAMIC_LOADER_TOOL
      Context()
        : m_dispatcher( new VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::ContextDispatcher(
            m_dynamicLoader.getProcAddress<PFN_vkGetInstanceProcAddr>( "vkGetInstanceProcAddr" ) ) )
#else
      Context( PFN_vkGetInstanceProcAddr getInstanceProcAddr )
        : m_dispatcher( new VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::ContextDispatcher( getInstanceProcAddr ) )
#endif
      {}

      ~Context() = default;

      Context( Context const & ) = delete;
      Context( Context && rhs ) VULKAN_HPP_NOEXCEPT
#if VULKAN_HPP_ENABLE_DYNAMIC_LOADER_TOOL
        : m_dynamicLoader( std::move( rhs.m_dynamicLoader ) )
        , m_dispatcher( rhs.m_dispatcher.release() )
#else
        : m_dispatcher( rhs.m_dispatcher.release() )
#endif
      {}
      Context & operator=( Context const & ) = delete;
      Context & operator=( Context && rhs ) VULKAN_HPP_NOEXCEPT
      {
        if ( this != &rhs )
        {
#if VULKAN_HPP_ENABLE_DYNAMIC_LOADER_TOOL
          m_dynamicLoader = std::move( rhs.m_dynamicLoader );
#endif
          m_dispatcher.reset( rhs.m_dispatcher.release() );
        }
        return *this;
      }

      VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::ContextDispatcher const * getDispatcher() const
      {
        VULKAN_HPP_ASSERT( m_dispatcher->getVkHeaderVersion() == VK_HEADER_VERSION );
        return &*m_dispatcher;
      }

      void swap( VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::Context & rhs )
      {
#if VULKAN_HPP_ENABLE_DYNAMIC_LOADER_TOOL
        std::swap( m_dynamicLoader, rhs.m_dynamicLoader );
#endif
        m_dispatcher.swap( rhs.m_dispatcher );
      }

${memberFunctionDeclarations}

    private:
#if VULKAN_HPP_ENABLE_DYNAMIC_LOADER_TOOL
      VULKAN_HPP_NAMESPACE::DynamicLoader                                                 m_dynamicLoader;
#endif
      std::unique_ptr<VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::ContextDispatcher> m_dispatcher;
    };

)";

  return replaceWithMap( contextTemplate, { { "memberFunctionDeclarations", generateRAIIHandleCommandDeclarations( handle, specialFunctions ) } } );
}

std::string VulkanHppGenerator::generateRAIIHandleDestructorCallArguments( std::string const &                                handleType,
                                                                           std::map<std::string, CommandData>::const_iterator destructorIt ) const
{
  std::string arguments;
  bool        encounteredArgument = false;
  for ( auto param : destructorIt->second.params )
  {
    if ( encounteredArgument )
    {
      arguments += ", ";
    }
    if ( param.type.type == handleType )
    {
      std::string handleName = param.name;
      if ( param.type.isValue() )
      {
        arguments += "static_cast<" + handleType + ">( m_" + handleName + " )";
      }
      else
      {
        arguments += "reinterpret_cast<" + handleType + " const *>( &m_" + stripPluralS( startLowerCase( stripPrefix( handleName, "p" ) ) ) + " )";
      }
    }
    else if ( param.type.type == "VkAllocationCallbacks" )
    {
      // vk::AllocationCallbacks is stored as a member of the handle class
      arguments += "reinterpret_cast<const VkAllocationCallbacks *>( m_allocator )";
    }
    else if ( isHandleType( param.type.type ) )
    {
      assert( param.arraySizes.empty() );
      std::string argument = "m_" + param.name;
      if ( param.type.isValue() )
      {
        arguments += "static_cast<" + param.type.type + ">( " + argument + " )";
      }
      else
      {
        assert( param.type.isConstPointer() );
        assert( !param.len.empty() &&
                ( std::find_if( destructorIt->second.params.begin(),
                                destructorIt->second.params.end(),
                                [&param]( ParamData const & pd ) { return pd.name == param.len; } ) != destructorIt->second.params.end() ) );
        arguments += "reinterpret_cast<" + param.type.type + " const *>( &" + argument + " )";
      }
    }
    else
    {
      assert( ( param.type.type == "uint32_t" ) && param.type.isValue() && param.arraySizes.empty() && param.len.empty() && !param.optional );
      assert( std::find_if( destructorIt->second.params.begin(),
                            destructorIt->second.params.end(),
                            [&param]( ParamData const & pd ) { return pd.len == param.name; } ) != destructorIt->second.params.end() );
      arguments += "1";
    }
    encounteredArgument = true;
  }
  return arguments;
}

std::tuple<std::string, std::string, std::string, std::string, std::string, std::string>
  VulkanHppGenerator::generateRAIIHandleDetails( std::pair<std::string, HandleData> const & handle ) const
{
  std::string getConstructorSuccessCode;
  bool        multiSuccessCodeContructor = isMultiSuccessCodeConstructor( handle.second.constructorIts );
  if ( multiSuccessCodeContructor )
  {
    getConstructorSuccessCode = R"(
    VULKAN_HPP_NAMESPACE::Result getConstructorSuccessCode() const
    {
      return m_constructorSuccessCode;
    }
)";
  }

  auto [parentType, parentName] = getParentTypeAndName( handle );

  std::string handleType = stripPrefix( handle.first, "Vk" );
  std::string handleName = generateRAIIHandleConstructorParamName( handle.first, handle.second.destructorIt );

  std::string clearMembers, moveConstructorInitializerList, moveAssignmentInstructions, memberVariables, swapMembers;

  if ( handle.second.destructorIt != m_commands.end() )
  {
    moveAssignmentInstructions = "          clear();";

    clearMembers = "        if ( m_" + handleName + " )\n";
    clearMembers += "        {\n";
    clearMembers += "          getDispatcher()->" + handle.second.destructorIt->first + "( " +
                    generateRAIIHandleDestructorCallArguments( handle.first, handle.second.destructorIt ) + " );\n";
    clearMembers += "        }";
    for ( auto const & destructorParam : handle.second.destructorIt->second.params )
    {
      std::string memberName, memberType;
      if ( destructorParam.type.type == "Vk" + parentType )
      {
        memberName = parentName;
        memberType = "VULKAN_HPP_NAMESPACE::" + parentType;
      }
      else if ( destructorParam.type.type == handle.first )
      {
        memberName = handleName;
        memberType = "VULKAN_HPP_NAMESPACE::" + handleType;
      }
      else if ( std::find_if( handle.second.destructorIt->second.params.begin(),
                              handle.second.destructorIt->second.params.end(),
                              [&destructorParam]( ParamData const & pd )
                              { return pd.len == destructorParam.name; } ) == handle.second.destructorIt->second.params.end() )
      {
        std::string name = destructorParam.name;
        if ( !destructorParam.type.isValue() )
        {
          name = startLowerCase( stripPrefix( name, "p" ) );
        }
        memberName = name;
        memberType = destructorParam.type.compose( "VULKAN_HPP_NAMESPACE" );
      }
      if ( !memberName.empty() )
      {
        clearMembers += "\n      m_" + memberName + " = nullptr;";
        moveConstructorInitializerList += "m_" + memberName + "( VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_" + memberName + ", {} ) ), ";
        moveAssignmentInstructions +=
          "\n          m_" + memberName + " = VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_" + memberName + ", {} );";
        memberVariables += "\n    " + memberType + " m_" + memberName + " = {};";
        swapMembers += "\n      std::swap( m_" + memberName + ", rhs.m_" + memberName + " );";
      }
    }
  }
  else
  {
    if ( !handle.second.secondLevelCommands.empty() )
    {
      assert( !handle.second.constructorIts.empty() );
      assert( !handle.second.constructorIts.front()->second.params.empty() );
      auto const & frontType = handle.second.constructorIts.front()->second.params.front().type.type;
      assert( isHandleType( frontType ) );
#if !defined( NDEBUG )
      auto handleIt = m_handles.find( "Vk" + parentType );
#endif
      assert( handleIt != m_handles.end() );
      assert( handleIt->second.parent == frontType );
      std::string frontName = handle.second.constructorIts.front()->second.params.front().name;

      clearMembers += "\n        m_" + frontName + " = nullptr;";
      moveConstructorInitializerList = "m_" + frontName + "( VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_" + frontName + ", {} ) ), ";
      moveAssignmentInstructions =
        "\n          m_" + frontName + " = VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_" + frontName + ", {} );";
      memberVariables = "\n    VULKAN_HPP_NAMESPACE::" + stripPrefix( frontType, "Vk" ) + " m_" + frontName + " = {};";
      swapMembers     = "\n      std::swap( m_" + frontName + ", rhs.m_" + frontName + " );";
    }
    clearMembers += "\n        m_" + handleName + " = nullptr;";
    moveConstructorInitializerList += "m_" + handleName + "( VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_" + handleName + ", {} ) ), ";
    moveAssignmentInstructions +=
      "\n          m_" + handleName + " = VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_" + handleName + ", {} );";
    memberVariables += "\n    VULKAN_HPP_NAMESPACE::" + handleType + " m_" + handleName + " = {};";
    swapMembers += "\n      std::swap( m_" + handleName + ", rhs.m_" + handleName + " );";
  }

  if ( multiSuccessCodeContructor )
  {
    clearMembers += "\n        m_constructorSuccessCode = VULKAN_HPP_NAMESPACE::Result::eErrorUnknown;";
    memberVariables += "\n    VULKAN_HPP_NAMESPACE::Result m_constructorSuccessCode = VULKAN_HPP_NAMESPACE::Result::eErrorUnknown;";
    swapMembers += "\n      std::swap( m_constructorSuccessCode, rhs.m_constructorSuccessCode );";
    moveConstructorInitializerList +=
      "m_constructorSuccessCode( VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_constructorSuccessCode, {} ) ), ";
    moveAssignmentInstructions +=
      "\n          m_constructorSuccessCode = VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_constructorSuccessCode, {} );";
  }

  if ( handle.first == "VkInstance" )
  {
    memberVariables += "\n      std::unique_ptr<VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::InstanceDispatcher> m_dispatcher;";
  }
  else if ( handle.first == "VkDevice" )
  {
    memberVariables += "\n      std::unique_ptr<VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::DeviceDispatcher> m_dispatcher;";
  }
  else if ( handle.second.constructorIts.front()->second.params.front().type.type == "VkDevice" )
  {
    memberVariables += "\n      VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::DeviceDispatcher const * m_dispatcher = nullptr;";
  }
  else
  {
    memberVariables += "\n      VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::InstanceDispatcher const * m_dispatcher = nullptr;";
  }
  clearMembers += "\n        m_dispatcher = nullptr;";
  swapMembers += "\n      std::swap( m_dispatcher, rhs.m_dispatcher );";

  if ( ( handle.first == "VkInstance" ) || ( handle.first == "VkDevice" ) )
  {
    moveConstructorInitializerList += "m_dispatcher( rhs.m_dispatcher.release() )";
    moveAssignmentInstructions += "\n        m_dispatcher.reset( rhs.m_dispatcher.release() );";
  }
  else
  {
    moveConstructorInitializerList += "m_dispatcher( VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_dispatcher, nullptr ) )";
    moveAssignmentInstructions += "\n        m_dispatcher = VULKAN_HPP_NAMESPACE::VULKAN_HPP_RAII_NAMESPACE::exchange( rhs.m_dispatcher, nullptr );";
  }

  return std::make_tuple( clearMembers, getConstructorSuccessCode, memberVariables, moveConstructorInitializerList, moveAssignmentInstructions, swapMembers );
}

std::string VulkanHppGenerator::generateRAIIHandleForwardDeclarations( std::vector<RequireData> const & requireData, std::string const & title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto handleIt = m_handles.find( type );
      if ( handleIt != m_handles.end() )
      {
        str += "  class " + stripPrefix( handleIt->first, "Vk" ) + ";\n";
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateRAIIHandles() const
{
  const std::string raiiHandlesTemplate = R"(
  //========================================
  //=== RAII HANDLE forward declarations ===
  //========================================

${forwardDeclarations}

  //====================
  //=== RAII HANDLES ===
  //====================

${raiiHandles}
)";

  std::string forwardDeclarations;
  for ( auto const & feature : m_features )
  {
    forwardDeclarations += generateRAIIHandleForwardDeclarations( feature.second.requireData, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    forwardDeclarations += generateRAIIHandleForwardDeclarations( extIt.second->second.requireData, extIt.second->first );
  }

  std::set<std::string> listedHandles;
  auto                  handleIt = m_handles.begin();
  assert( handleIt->first.empty() );
  std::string raiiHandles = generateRAIIHandleContext( *handleIt, m_RAIISpecialFunctions );
  for ( ++handleIt; handleIt != m_handles.end(); ++handleIt )
  {
    raiiHandles += generateRAIIHandle( *handleIt, listedHandles, m_RAIISpecialFunctions );
  }
  return replaceWithMap( raiiHandlesTemplate, { { "forwardDeclarations", forwardDeclarations }, { "raiiHandles", raiiHandles } } );
}

std::string VulkanHppGenerator::generateRAIIHandleSingularConstructorArguments( std::pair<std::string, HandleData> const &         handle,
                                                                                std::map<std::string, CommandData>::const_iterator constructorIt ) const
{
  std::string arguments = startLowerCase( stripPrefix( handle.first, "Vk" ) );
  if ( handle.second.destructorIt != m_commands.end() )
  {
    auto [parentType, parentName] = getParentTypeAndName( handle );
    parentType                    = "Vk" + parentType;
    for ( auto const & destructorParam : handle.second.destructorIt->second.params )
    {
      if ( ( destructorParam.type.type != parentType ) && ( destructorParam.type.type != handle.first ) &&
           ( std::find_if( handle.second.destructorIt->second.params.begin(),
                           handle.second.destructorIt->second.params.end(),
                           [&destructorParam]( ParamData const & pd )
                           { return pd.len == destructorParam.name; } ) == handle.second.destructorIt->second.params.end() ) )
      {
        if ( std::find_if( constructorIt->second.params.begin(),
                           constructorIt->second.params.end(),
                           [&destructorParam]( ParamData const & pd )
                           { return pd.type.type == destructorParam.type.type; } ) != constructorIt->second.params.end() )
        {
          if ( isHandleType( destructorParam.type.type ) )
          {
            assert( destructorParam.type.isValue() );
            arguments += ", static_cast<" + destructorParam.type.type + ">( *" + destructorParam.name + " )";
          }
          else
          {
            assert( destructorParam.type.type == "VkAllocationCallbacks" );
            arguments += ", allocator";
          }
        }
        else
        {
#if !defined( NDEBUG )
          bool found = false;
#endif
          for ( auto const & constructorParam : constructorIt->second.params )
          {
            auto structureIt = m_structures.find( constructorParam.type.type );
            if ( structureIt != m_structures.end() )
            {
              auto memberIt = findStructMemberItByType( destructorParam.type.type, structureIt->second.members );
              if ( memberIt != structureIt->second.members.end() )
              {
#if !defined( NDEBUG )
                found = true;
#endif
                assert( !constructorParam.type.isValue() );
                std::string argument = startLowerCase( stripPrefix( constructorParam.name, "p" ) ) + "." + memberIt->name;
                if ( isHandleType( memberIt->type.type ) )
                {
                  argument = "static_cast<" + memberIt->type.type + ">( " + argument + " )";
                }
                arguments += ", " + argument;
                break;
              }
            }
          }
          assert( found );
        }
      }
    }
  }
  return arguments;
}

std::string VulkanHppGenerator::generateRAIIHandleVectorSizeCheck( std::string const &                           name,
                                                                   CommandData const &                           commandData,
                                                                   size_t                                        initialSkipCount,
                                                                   std::map<size_t, std::vector<size_t>> const & countToVectorMap,
                                                                   std::set<size_t> const &                      skippedParams ) const
{
  std::string const throwTemplate =
    R"#(    if ( ${zeroSizeCheck}${firstVectorName}.size() != ${secondVectorName}.size() )
  {
    throw LogicError( VULKAN_HPP_NAMESPACE_STRING "::${className}::${commandName}: ${firstVectorName}.size() != ${secondVectorName}.size()" );
  })#";

  std::string const throwTemplateVoid =
    R"#(    if ( ${zeroSizeCheck}${firstVectorName}.size() * sizeof( ${firstDataType} ) != ${secondVectorName}.size() * sizeof( ${secondDataType} ) )
  {
    throw LogicError( VULKAN_HPP_NAMESPACE_STRING "::${className}::${commandName}: ${firstVectorName}.size() * sizeof( ${firstDataType} ) != ${secondVectorName}.size() * sizeof( ${secondDataType} )" );
  })#";

  std::string const throwTemplateByLen = R"#(    if ( ${vectorName}.size() != ${sizeValue} )
    {
      throw LogicError( VULKAN_HPP_NAMESPACE_STRING "::${className}::${commandName}: ${vectorName}.size() != ${sizeValue}" );
    })#";

  std::string className   = stripPrefix( commandData.params[initialSkipCount - 1].type.type, "Vk" );
  std::string commandName = generateCommandName( name, commandData.params, initialSkipCount, m_tags, false, false );

  std::string sizeChecks;
  for ( auto const & cvm : countToVectorMap )
  {
    size_t      defaultStartIndex = determineDefaultStartIndex( commandData.params, skippedParams );
    std::string firstVectorName   = startLowerCase( stripPrefix( commandData.params[cvm.second[0]].name, "p" ) );

    if ( cvm.second.size() == 1 )
    {
      assert( isLenByStructMember( commandData.params[cvm.second[0]].len, commandData.params[cvm.first] ) );

      std::vector<std::string> lenParts = tokenize( commandData.params[cvm.second[0]].len, "->" );
      assert( lenParts.size() == 2 );
      std::string sizeValue = startLowerCase( stripPrefix( lenParts[0], "p" ) ) + "." + lenParts[1];
      sizeChecks += replaceWithMap(
        throwTemplateByLen, { { "className", className }, { "commandName", commandName }, { "sizeValue", sizeValue }, { "vectorName", firstVectorName } } );
    }
    else
    {
      for ( size_t i = 1; i < cvm.second.size(); i++ )
      {
        std::string secondVectorName  = startLowerCase( stripPrefix( commandData.params[cvm.second[i]].name, "p" ) );
        bool        withZeroSizeCheck = commandData.params[cvm.second[i]].optional && ( defaultStartIndex <= cvm.second[i] );
        if ( commandData.params[cvm.second[0]].type.type == "void" )
        {
          assert( commandData.params[cvm.second[i]].type.type == "void" );
          std::string firstDataType  = stripPrefix( commandData.params[cvm.second[0]].name, "p" ) + "Type";
          std::string secondDataType = stripPrefix( commandData.params[cvm.second[i]].name, "p" ) + "Type";
          sizeChecks += replaceWithMap( throwTemplateVoid,
                                        { { "firstDataType", firstDataType },
                                          { "firstVectorName", firstVectorName },
                                          { "className", className },
                                          { "commandName", commandName },
                                          { "secondDataType", secondDataType },
                                          { "secondVectorName", secondVectorName },
                                          { "zeroSizeCheck", withZeroSizeCheck ? ( "!" + secondVectorName + ".empty() && " ) : "" } } );
        }
        else
        {
          sizeChecks += replaceWithMap( throwTemplate,
                                        { { "firstVectorName", firstVectorName },
                                          { "className", className },
                                          { "commandName", commandName },
                                          { "secondVectorName", secondVectorName },
                                          { "zeroSizeCheck", withZeroSizeCheck ? ( "!" + secondVectorName + ".empty() && " ) : "" } } );
        }
        if ( i + 1 < cvm.second.size() )
        {
          sizeChecks += "\n";
        }
      }
    }
  }
  if ( !sizeChecks.empty() )
  {
    sizeChecks += "\n";
  }

  return sizeChecks;
}

std::string VulkanHppGenerator::generateResultAssignment( CommandData const & commandData ) const
{
  std::string resultAssignment;
  if ( ( commandData.returnType != "void" ) &&
       !( ( commandData.returnType == "VkResult" ) && ( commandData.successCodes.size() == 1 ) && commandData.errorCodes.empty() ) )
  {
    resultAssignment = commandData.returnType + " result = ";
  }
  return resultAssignment;
}

std::string VulkanHppGenerator::generateResultCheck(
  CommandData const & commandData, std::string const & className, std::string const & classSeparator, std::string commandName, bool enumerating ) const
{
  std::string resultCheck;
  if ( !commandData.errorCodes.empty() )
  {
    std::string successCodeList = generateSuccessCodeList( commandData.successCodes, enumerating );

    std::string const resultCheckTemplate =
      R"(resultCheck( static_cast<VULKAN_HPP_NAMESPACE::Result>( result ), VULKAN_HPP_NAMESPACE_STRING "::${className}${classSeparator}${commandName}"${successCodeList} );)";

    resultCheck = replaceWithMap(
      resultCheckTemplate,
      { { "className", className }, { "classSeparator", classSeparator }, { "commandName", commandName }, { "successCodeList", successCodeList } } );
  }
  return resultCheck;
}

// Intended only for `enum class Result`!
std::string VulkanHppGenerator::generateResultExceptions() const
{
  const std::string templateString = R"(
${enter}  class ${className} : public SystemError
  {
  public:
    ${className}( std::string const & message )
      : SystemError( make_error_code( ${enumName}::${enumMemberName} ), message ) {}
    ${className}( char const * message )
      : SystemError( make_error_code( ${enumName}::${enumMemberName} ), message ) {}
  };
${leave})";

  std::string str;
  auto        enumIt = m_enums.find( "VkResult" );
  for ( auto const & value : enumIt->second.values )
  {
    if ( value.name.starts_with( "VK_ERROR" ) )
    {
      auto [enter, leave]   = generateProtection( value.extension, value.protect );
      std::string valueName = generateEnumValueName( enumIt->first, value.name, false, m_tags );
      str += replaceWithMap( templateString,
                             { { "className", stripPrefix( valueName, "eError" ) + "Error" },
                               { "enter", enter },
                               { "enumName", stripPrefix( enumIt->first, "Vk" ) },
                               { "enumMemberName", valueName },
                               { "leave", leave } } );
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateReturnStatement( std::string const & commandName,
                                                         CommandData const & commandData,
                                                         std::string const & returnVariable,
                                                         std::string const & returnType,
                                                         std::string const & dataType,
                                                         size_t              initialSkipCount,
                                                         size_t              returnParam,
                                                         bool                unique,
                                                         bool                enumerating,
                                                         bool                raii ) const
{
  std::string returnStatement;
  if ( commandData.returnType.starts_with( "Vk" ) )
  {
    if ( ( commandData.successCodes.size() == 1 ) || enumerating )
    {
      assert( commandData.successCodes[0] == "VK_SUCCESS" );
      if ( raii || commandData.errorCodes.empty() )
      {
        if ( !returnVariable.empty() )
        {
          returnStatement = "return " + returnVariable + ";";
        }
      }
      else
      {
        if ( returnVariable.empty() )
        {
          assert( !unique );
          returnStatement = "return createResultValueType( static_cast<VULKAN_HPP_NAMESPACE::Result>( result ) );";
        }
        else if ( unique )
        {
          assert( returnParam != INVALID_INDEX );
          returnStatement = "return createResultValueType( static_cast<VULKAN_HPP_NAMESPACE::Result>( result ), ";
          if ( dataType.starts_with( "std::" ) )
          {
            returnStatement += "std::move( unique" + startUpperCase( returnVariable ) + " )";
          }
          else
          {
            returnStatement += "UniqueHandle<" + dataType + ", Dispatch>( " + returnVariable + ", " +
                               generateObjectDeleter( commandName, commandData, initialSkipCount, returnParam ) + " )";
          }
          returnStatement += " );";
        }
        else
        {
          returnStatement = "return createResultValueType( static_cast<VULKAN_HPP_NAMESPACE::Result>( result ), " + returnVariable + " );";
        }
      }
    }
    else
    {
      if ( returnVariable.empty() )
      {
        assert( !unique );
        returnStatement = "return static_cast<VULKAN_HPP_NAMESPACE::" + stripPrefix( commandData.returnType, "Vk" ) + ">( result );";
      }
      else if ( unique )
      {
        assert( returnParam != INVALID_INDEX );
        assert( returnType.starts_with( "ResultValue<" ) && returnType.ends_with( ">" ) );
        returnStatement = "return " + returnType + "( static_cast<VULKAN_HPP_NAMESPACE::Result>( result ), ";
        if ( dataType.starts_with( "std::" ) )
        {
          returnStatement += "std::move( unique" + startUpperCase( returnVariable ) + " )";
        }
        else
        {
          returnStatement += "UniqueHandle<" + dataType + ", Dispatch>( " + returnVariable + ", " +
                             generateObjectDeleter( commandName, commandData, initialSkipCount, returnParam ) + " )";
        }
        returnStatement += " );";
      }
      else
      {
        assert( returnType.starts_with( raii ? "std::pair<VULKAN_HPP_NAMESPACE::Result, " : "ResultValue<" ) && returnType.ends_with( ">" ) );
        returnStatement =
          "return " + ( raii ? "std::make_pair" : returnType ) + "( static_cast<VULKAN_HPP_NAMESPACE::Result>( result ), " + returnVariable + " );";
      }
    }
  }
  else
  {
    assert( !unique );
    if ( returnVariable.empty() )
    {
      if ( commandData.returnType != "void" )
      {
        returnStatement = "return result;";
      }
    }
    else
    {
      returnStatement = "return " + returnVariable + ";";
    }
  }
  return returnStatement;
}

std::string VulkanHppGenerator::generateReturnType( CommandData const &                       commandData,
                                                    std::vector<size_t> const &               returnParams,
                                                    std::map<size_t, VectorParamData> const & vectorParams,
                                                    bool                                      unique,
                                                    bool                                      chained,
                                                    bool                                      raii,
                                                    std::string const &                       dataType ) const
{
  std::string modifiedDataType = dataType;
  if ( chained )
  {
    assert( !unique );
    modifiedDataType = dataType.starts_with( "std::vector" )
                       ? ( std::string( "std::vector<StructureChain" ) + ( raii ? "" : ", StructureChainAllocator" ) + "> " )
                       : " StructureChain<X, Y, Z...> ";
  }
  else if ( unique )
  {
    assert( !chained );
    assert( ( returnParams.size() == 1 ) && isHandleType( commandData.params[returnParams[0]].type.type ) );
    if ( dataType.starts_with( "std::vector" ) )
    {
      auto from = dataType.find( '<' ) + 1;
      assert( from != std::string::npos );
      auto to = dataType.find( '>', from );
      assert( to == dataType.length() - 1 );
      std::string type = dataType.substr( from, to - from );
      assert( type.starts_with( "VULKAN_HPP_NAMESPACE::" ) );
      modifiedDataType.replace( from, to - from, "UniqueHandle<" + type + ", Dispatch>, " + stripPrefix( type, "VULKAN_HPP_NAMESPACE::" ) + "Allocator" );
    }
    else
    {
      assert( !dataType.starts_with( "std::" ) );
      modifiedDataType = "UniqueHandle<" + dataType + ", Dispatch>";
    }
  }

  std::string returnType;
  if ( ( 1 < commandData.successCodes.size() ) && returnParams.empty() && !chained )
  {
    assert( ( commandData.returnType == "VkResult" ) && !unique );
    returnType = "VULKAN_HPP_NAMESPACE::Result";
  }
  else if ( ( commandData.returnType != "VkResult" ) && ( commandData.returnType != "void" ) )
  {
    assert( returnParams.empty() && !chained && !unique );
    if ( commandData.returnType.starts_with( "Vk" ) )
    {
      returnType = generateNamespacedType( commandData.returnType );
    }
    else
    {
      returnType = commandData.returnType;
    }
  }
  else if ( ( commandData.returnType == "void" ) ||
            ( ( commandData.returnType == "VkResult" ) && ( commandData.successCodes.size() == 1 ) && ( commandData.errorCodes.empty() || raii ) ) ||
            ( chained && raii ) )
  {
    assert( !unique );
    assert( ( commandData.returnType != "void" ) || ( returnParams.size() <= 2 ) );
    returnType = modifiedDataType;
  }
  else
  {
    assert( commandData.returnType == "VkResult" );
    assert( !commandData.successCodes.empty() && ( commandData.successCodes[0] == "VK_SUCCESS" ) );
    if ( ( 1 < commandData.successCodes.size() ) && ( ( returnParams.size() == 1 ) || ( ( returnParams.size() == 2 ) && vectorParams.empty() ) ) )
    {
      assert( !commandData.errorCodes.empty() && !chained );
      returnType = ( raii ? "std::pair<VULKAN_HPP_NAMESPACE::Result, " : "ResultValue<" ) + modifiedDataType + ">";
    }
    else
    {
      assert(
        ( ( commandData.successCodes.size() == 1 ) || ( ( commandData.successCodes.size() == 2 ) && ( commandData.successCodes[1] == "VK_INCOMPLETE" ) ) ) &&
        ( returnParams.size() <= 3 ) );
      returnType = raii ? modifiedDataType : ( "typename ResultValueType<" + modifiedDataType + ">::type" );
    }
  }
  return returnType;
}

std::string VulkanHppGenerator::generateReturnVariable( CommandData const &                       commandData,
                                                        std::vector<size_t> const &               returnParams,
                                                        std::map<size_t, VectorParamData> const & vectorParams,
                                                        bool                                      chained,
                                                        bool                                      singular ) const
{
  std::string returnVariable;
  switch ( returnParams.size() )
  {
    case 0: break;  // no return variable
    case 1:
      if ( chained )
      {
        returnVariable = "structureChain";
      }
      else
      {
        returnVariable = startLowerCase( stripPrefix( commandData.params[returnParams[0]].name, "p" ) );
        if ( singular )
        {
          returnVariable = stripPluralS( returnVariable );
        }
      }
      break;
    case 2:
      if ( chained )
      {
        returnVariable = "structureChains";
      }
      else
      {
        auto vectorParamIt = vectorParams.find( returnParams[1] );
        if ( vectorParamIt == vectorParams.end() )
        {  // the return variable is simply named "data", and holds the multi-return value stuff
          returnVariable = "data";
        }
        else
        {
          assert( vectorParamIt->second.lenParam == returnParams[0] );
          assert( !singular );
          returnVariable = startLowerCase( stripPrefix( commandData.params[returnParams[1]].name, "p" ) );
        }
      }
      break;
    case 3:
      assert( !chained && !singular );
      assert( ( vectorParams.size() == 2 ) && ( vectorParams.begin()->first == returnParams[1] ) &&
              ( vectorParams.begin()->second.lenParam == returnParams[0] ) && ( std::next( vectorParams.begin() )->first == returnParams[2] ) &&
              ( std::next( vectorParams.begin() )->second.lenParam == returnParams[0] ) );
      returnVariable = "data";
      break;
  }
  return returnVariable;
}

std::string VulkanHppGenerator::generateSizeCheck( std::vector<std::vector<MemberData>::const_iterator> const & arrayIts,
                                                   std::string const &                                          structName,
                                                   bool                                                         mutualExclusiveLens ) const
{
  std::string sizeCheck;
  if ( 1 < arrayIts.size() )
  {
    static const std::string throwTextTemplate = R"(      if ( ${throwCheck} )
      {
        throw LogicError( VULKAN_HPP_NAMESPACE_STRING"::${structName}::${structName}: ${throwCheck}" );
      }
)";

    std::string assertionText, throwText;
    if ( mutualExclusiveLens )
    {
      // exactly one of the arrays has to be non-empty
      std::string sum;
      for ( auto it : arrayIts )
      {
        sum += "!" + startLowerCase( stripPrefix( it->name, "p" ) ) + "_.empty() + ";
      }
      sum.resize( sum.size() - 3 );
      assertionText += "      VULKAN_HPP_ASSERT( ( " + sum + " ) <= 1);\n";
      throwText += replaceWithMap( throwTextTemplate, { { "structName", structName }, { "throwCheck", "1 < ( " + sum + " )" } } );
    }
    else
    {
      for ( size_t first = 0; first + 1 < arrayIts.size(); ++first )
      {
        assert( arrayIts[first]->name.starts_with( "p" ) );
        std::string firstName = startLowerCase( stripPrefix( arrayIts[first]->name, "p" ) ) + "_";
        for ( auto second = first + 1; second < arrayIts.size(); ++second )
        {
          assert( arrayIts[second]->name.starts_with( "p" ) );
          std::string secondName     = startLowerCase( stripPrefix( arrayIts[second]->name, "p" ) ) + "_";
          std::string assertionCheck = firstName + ".size() == " + secondName + ".size()";
          std::string throwCheck     = firstName + ".size() != " + secondName + ".size()";
          if ( ( !arrayIts[first]->optional.empty() && arrayIts[first]->optional.front() ) ||
               ( !arrayIts[second]->optional.empty() && arrayIts[second]->optional.front() ) )
          {
            assertionCheck = "( " + assertionCheck + " )";
            throwCheck     = "( " + throwCheck + " )";
            if ( !arrayIts[second]->optional.empty() && arrayIts[second]->optional.front() )
            {
              assertionCheck = secondName + ".empty() || " + assertionCheck;
              throwCheck     = "!" + secondName + ".empty() && " + throwCheck;
            }
            if ( !arrayIts[first]->optional.empty() && arrayIts[first]->optional.front() )
            {
              assertionCheck = firstName + ".empty() || " + assertionCheck;
              throwCheck     = "!" + firstName + ".empty() && " + throwCheck;
            }
          }
          assertionText += "      VULKAN_HPP_ASSERT( " + assertionCheck + " );\n";
          throwText += replaceWithMap( throwTextTemplate, { { "structName", structName }, { "throwCheck", throwCheck } } );
        }
      }
    }
    sizeCheck += "\n#ifdef VULKAN_HPP_NO_EXCEPTIONS\n" + assertionText + "#else\n" + throwText + "#endif /*VULKAN_HPP_NO_EXCEPTIONS*/\n" + "    ";
  }
  return sizeCheck;
}

std::string VulkanHppGenerator::generateStaticAssertions() const
{
  std::string staticAssertions;
  for ( auto const & feature : m_features )
  {
    staticAssertions += generateStaticAssertions( feature.second.requireData, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    staticAssertions += generateStaticAssertions( extIt.second->second.requireData, extIt.second->first );
  }
  return staticAssertions;
}

std::string VulkanHppGenerator::generateStaticAssertions( std::vector<RequireData> const & requireData, std::string const & title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto handleIt = m_handles.find( type );
      if ( handleIt != m_handles.end() )
      {
        std::string const assertionTemplate = R"(
VULKAN_HPP_STATIC_ASSERT( sizeof( VULKAN_HPP_NAMESPACE::${className} ) == sizeof( Vk${className} ), "handle and wrapper have different size!" );
VULKAN_HPP_STATIC_ASSERT( std::is_nothrow_move_constructible<VULKAN_HPP_NAMESPACE::${className}>::value, "${className} is not nothrow_move_constructible!" );
)";
        str += replaceWithMap( assertionTemplate, { { "className", stripPrefix( handleIt->first, "Vk" ) } } );
      }
      else
      {
        auto structIt = m_structures.find( type );
        if ( structIt != m_structures.end() )
        {
          std::string const assertionTemplate = R"(
VULKAN_HPP_STATIC_ASSERT( sizeof( VULKAN_HPP_NAMESPACE::${structureType} ) == sizeof( Vk${structureType} ), "struct and wrapper have different size!" );
VULKAN_HPP_STATIC_ASSERT( std::is_standard_layout<VULKAN_HPP_NAMESPACE::${structureType}>::value, "struct wrapper is not a standard layout!" );
VULKAN_HPP_STATIC_ASSERT( std::is_nothrow_move_constructible<VULKAN_HPP_NAMESPACE::${structureType}>::value, "${structureType} is not nothrow_move_constructible!" );
)";
          str += replaceWithMap( assertionTemplate, { { "structureType", stripPrefix( structIt->first, "Vk" ) } } );
        }
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateStruct( std::pair<std::string, StructureData> const & structure, std::set<std::string> & listedStructs ) const
{
  assert( listedStructs.find( structure.first ) == listedStructs.end() );

  std::string str;
  for ( auto const & member : structure.second.members )
  {
    auto structIt = m_structures.find( member.type.type );
    if ( ( structIt != m_structures.end() ) && ( structure.first != member.type.type ) && ( listedStructs.find( member.type.type ) == listedStructs.end() ) )
    {
      str += generateStruct( *structIt, listedStructs );
    }
  }

  if ( !structure.second.subStruct.empty() )
  {
    auto structureIt = m_structures.find( structure.second.subStruct );
    if ( ( structureIt != m_structures.end() ) && ( listedStructs.find( structureIt->first ) == listedStructs.end() ) )
    {
      str += generateStruct( *structureIt, listedStructs );
    }
  }

  if ( structure.second.isUnion )
  {
    str += generateUnion( structure );
  }
  else
  {
    str += generateStructure( structure );
  }

  listedStructs.insert( structure.first );
  return str;
}

std::string VulkanHppGenerator::generateStructAssignmentOperators( std::pair<std::string, StructureData> const & structData ) const
{
  static const std::string assignmentFromVulkanType = R"(
    ${structName} & operator=( ${structName} const & rhs ) VULKAN_HPP_NOEXCEPT = default;

    ${structName} & operator=( Vk${structName} const & rhs ) VULKAN_HPP_NOEXCEPT
    {
      *this = *reinterpret_cast<VULKAN_HPP_NAMESPACE::${structName} const *>( &rhs );
      return *this;
    }
)";
  return replaceWithMap( assignmentFromVulkanType, { { "structName", stripPrefix( structData.first, "Vk" ) } } );
}

std::string VulkanHppGenerator::generateStructCompareOperators( std::pair<std::string, StructureData> const & structData ) const
{
  static const std::set<std::string> simpleTypes = { "char",   "double",  "DWORD",    "float",    "HANDLE",  "HINSTANCE", "HMONITOR",
                                                     "HWND",   "int",     "int8_t",   "int16_t",  "int32_t", "int64_t",   "LPCWSTR",
                                                     "size_t", "uint8_t", "uint16_t", "uint32_t", "uint64_t" };
  // two structs are compared by comparing each of the elements
  std::string compareMembers, spaceshipMembers;
  std::string intro             = "";
  bool        nonDefaultCompare = false;
  std::string spaceshipOrdering = containsFloatingPoints( structData.second.members ) ? "std::partial_ordering" : "std::strong_ordering";
  for ( size_t i = 0; i < structData.second.members.size(); i++ )
  {
    MemberData const & member = structData.second.members[i];
    auto               typeIt = m_types.find( member.type.type );
    assert( typeIt != m_types.end() );
    if ( ( typeIt->second.category == TypeCategory::Requires ) && member.type.postfix.empty() && ( simpleTypes.find( member.type.type ) == simpleTypes.end() ) )
    {
      nonDefaultCompare = true;
      // this type might support operator==() or operator<=>()... that is, use memcmp
      compareMembers += intro + "( memcmp( &" + member.name + ", &rhs." + member.name + ", sizeof( " + member.type.type + " ) ) == 0 )";

      static const std::string spaceshipMemberTemplate =
        R"(      if ( auto cmp = memcmp( &${name}, &rhs.${name}, sizeof( ${type} ) ); cmp != 0 )
        return ( cmp < 0 ) ? ${ordering}::less : ${ordering}::greater;
)";
      spaceshipMembers +=
        replaceWithMap( spaceshipMemberTemplate, { { "name", member.name }, { "ordering", spaceshipOrdering }, { "type", member.type.type } } );
    }
    else if ( member.type.type == "char" && !member.len.empty() )
    {
      // compare null-terminated strings
      nonDefaultCompare = true;
      assert( member.len.size() < 3 );
      if ( member.len.size() == 1 )
      {
        assert( member.len[0] == "null-terminated" );
        compareMembers += intro + "( ( " + member.name + " == rhs." + member.name + " ) || ( strcmp( " + member.name + ", rhs." + member.name + " ) == 0 ) )";

        static const std::string spaceshipMemberTemplate =
          R"(     if ( ${name} != rhs.${name} )
        if ( auto cmp = strcmp( ${name}, rhs.${name} ); cmp != 0 )
          return ( cmp < 0 ) ? ${ordering}::less : ${ordering}::greater;
)";
        spaceshipMembers += replaceWithMap( spaceshipMemberTemplate, { { "name", member.name }, { "ordering", spaceshipOrdering } } );
      }
      else
      {
        assert( member.len[1] == "null-terminated" );
        static const std::string commpareMemberTemplate = R"(      [this, rhs]
      {
        bool equal = true;
        for ( size_t i = 0; equal && ( i < ${count} ); ++i )
        {
          equal = ( ( ${name}[i] == rhs.${name}[i] ) || ( strcmp( ${name}[i], rhs.${name}[i] ) == 0 ) );
        }
        return equal;
      }())";
        compareMembers += intro + replaceWithMap( commpareMemberTemplate, { { "count", member.len[0] }, { "name", member.name } } );

        static const std::string spaceshipMemberTemplate = R"(      for ( size_t i = 0; i < ${count}; ++i )
      {
        if ( ${name}[i] != rhs.${name}[i] )
          if ( auto cmp = strcmp( ${name}[i], rhs.${name}[i] ); cmp != 0 )
            return cmp < 0 ? ${ordering}::less : ${ordering}::greater;
      }
)";
        spaceshipMembers +=
          replaceWithMap( spaceshipMemberTemplate, { { "count", member.len[0] }, { "name", member.name }, { "ordering", spaceshipOrdering } } );
      }
    }
    else
    {
      // for all others, we use the operator== of that type
      compareMembers += intro + "( " + member.name + " == rhs." + member.name + " )";
      spaceshipMembers += "      if ( auto cmp = " + member.name + " <=> rhs." + member.name + "; cmp != 0 ) return cmp;\n";
    }
    intro = "\n          && ";
  }

  std::string structName = stripPrefix( structData.first, "Vk" );

  std::string compareBody, spaceshipOperator, spaceshipOperatorIf, spaceshipOperatorElse, spaceshipOperatorEndif;
  if ( nonDefaultCompare )
  {
    compareBody = "      return " + compareMembers + ";";

    if ( !containsFuncPointer( structData.first ) )
    {
      static const std::string spaceshipOperatorTemplate =
        R"(    ${ordering} operator<=>( ${name} const & rhs ) const VULKAN_HPP_NOEXCEPT
    {
${spaceshipMembers}
      return ${ordering}::equivalent;
    })";
      spaceshipOperatorIf = "#if defined(VULKAN_HPP_HAS_SPACESHIP_OPERATOR)";
      spaceshipOperator =
        replaceWithMap( spaceshipOperatorTemplate, { { "name", structName }, { "ordering", spaceshipOrdering }, { "spaceshipMembers", spaceshipMembers } } );
      spaceshipOperatorElse  = "#endif\n";
      spaceshipOperatorEndif = "";
    }
  }
  else
  {
    // use reflection only if VULKAN_HPP_USE_REFLECT is defined
    static const std::string compareBodyTemplate = R"(#if defined( VULKAN_HPP_USE_REFLECT )
      return this->reflect() == rhs.reflect();
#else
      return ${compareMembers};
#endif)";
    compareBody                                  = replaceWithMap( compareBodyTemplate, { { "compareMembers", compareMembers } } );

    if ( !containsFuncPointer( structData.first ) )
    {
      spaceshipOperatorIf    = "#if defined(VULKAN_HPP_HAS_SPACESHIP_OPERATOR)";
      spaceshipOperator      = "auto operator<=>( " + structName + " const & ) const = default;";
      spaceshipOperatorElse  = "#else";
      spaceshipOperatorEndif = "#endif\n";
    }
  }

  static const std::string compareTemplate = R"(
${spaceshipOperatorIf}
${spaceshipOperator}
${spaceshipOperatorElse}
    bool operator==( ${name} const & rhs ) const VULKAN_HPP_NOEXCEPT
    {
${compareBody}
    }

    bool operator!=( ${name} const & rhs ) const VULKAN_HPP_NOEXCEPT
    {
      return !operator==( rhs );
    }
${spaceshipOperatorEndif})";

  return replaceWithMap( compareTemplate,
                         { { "name", structName },
                           { "compareBody", compareBody },
                           { "spaceshipOperator", spaceshipOperator },
                           { "spaceshipOperatorElse", spaceshipOperatorElse },
                           { "spaceshipOperatorEndif", spaceshipOperatorEndif },
                           { "spaceshipOperatorIf", spaceshipOperatorIf } } );
}

std::string VulkanHppGenerator::generateStructConstructors( std::pair<std::string, StructureData> const & structData ) const
{
  // the constructor with all the elements as arguments, with defaults
  // and the simple copy constructor from the corresponding vulkan structure
  static const std::string constructors = R"(
    ${constexpr}${structName}(${arguments}) VULKAN_HPP_NOEXCEPT
    ${initializers}
    {}

    ${constexpr}${structName}( ${structName} const & rhs ) VULKAN_HPP_NOEXCEPT = default;

    ${structName}( Vk${structName} const & rhs ) VULKAN_HPP_NOEXCEPT
      : ${structName}( *reinterpret_cast<${structName} const *>( &rhs ) )
    {}
)";

  std::string arguments, initializers;
  bool        listedArgument = false;
  bool        firstArgument  = true;
  for ( auto const & member : structData.second.members )
  {
    // gather the arguments
    std::string argument = generateStructConstructorArgument( listedArgument, member, true );
    if ( !argument.empty() )
    {
      listedArgument = true;
      arguments += argument;
    }

    // gather the initializers; skip members with exactly one legal value
    if ( member.value.empty() )
    {
      initializers += std::string( firstArgument ? ": " : ", " ) + member.name + "( " + member.name + "_ )";
      firstArgument = false;
    }
  }
  auto pNextIt = std::find_if( structData.second.members.begin(), structData.second.members.end(), []( MemberData const & md ) { return md.name == "pNext"; } );
  if ( pNextIt != structData.second.members.end() )
  {
    // add pNext as a last optional argument to the constructor
    arguments += std::string( listedArgument ? ", " : "" ) + pNextIt->type.compose( "VULKAN_HPP_NAMESPACE" ) + " pNext_ = nullptr";
  }

  std::string str = replaceWithMap( constructors,
                                    { { "arguments", arguments },
                                      { "constexpr", generateConstexprString( structData.first ) },
                                      { "initializers", initializers },
                                      { "structName", stripPrefix( structData.first, "Vk" ) } } );

  str += generateStructConstructorsEnhanced( structData );
  return str;
}

std::string VulkanHppGenerator::generateStructConstructorsEnhanced( std::pair<std::string, StructureData> const & structData ) const
{
  auto memberIts = findAll( structData.second.members.begin(),
                            structData.second.members.end(),
                            []( MemberData const & md ) {
                              return !md.len.empty() && !( md.len[0] == "null-terminated" ) &&
                                     ( ( altLens.find( md.len[0] ) == altLens.end() ) || ( md.len[0] == "codeSize / 4" ) );
                            } );
  if ( !memberIts.empty() )
  {
    // map from len-members to all the array members using that len
    std::map<std::vector<MemberData>::const_iterator, std::vector<std::vector<MemberData>::const_iterator>> lenIts;
    for ( auto const & mit : memberIts )
    {
      std::string lenName = ( mit->len.front() == "codeSize / 4" ) ? "codeSize" : mit->len.front();
      auto        lenIt   = findStructMemberIt( lenName, structData.second.members );
      assert( lenIt != mit );
      lenIts[lenIt].push_back( mit );
    }

    std::string arguments, initializers;
    bool        listedArgument = false;
    bool        firstArgument  = true;
    bool        arrayListed    = false;
    std::string templateHeader, sizeChecks;
    for ( auto mit = structData.second.members.begin(); mit != structData.second.members.end(); ++mit )
    {
      // gather the initializers
      if ( mit->name == "pNext" )  // for pNext, we just get the initializer... the argument is added at the end
      {
        initializers += std::string( firstArgument ? ":" : "," ) + " pNext( pNext_ )";
        firstArgument = false;
      }
      else if ( mit->value.empty() )  // skip constant members
      {
        auto litit = lenIts.find( mit );
        if ( litit != lenIts.end() )
        {
          // len arguments just have an initalizer, from the ArrayProxyNoTemporaries size
          initializers +=
            ( firstArgument ? ": " : ", " ) + mit->name + "( " + generateLenInitializer( mit, litit, structData.second.mutualExclusiveLens ) + " )";
          sizeChecks += generateSizeCheck( litit->second, stripPrefix( structData.first, "Vk" ), structData.second.mutualExclusiveLens );
        }
        else if ( std::find( memberIts.begin(), memberIts.end(), mit ) != memberIts.end() )
        {
          assert( mit->name.starts_with( "p" ) );
          std::string argumentName = startLowerCase( stripPrefix( mit->name, "p" ) ) + "_";

          assert( mit->type.postfix.ends_with( "*" ) );
          std::string argumentType = trimEnd( stripPostfix( mit->type.compose( "VULKAN_HPP_NAMESPACE" ), "*" ) );
          if ( ( mit->type.type == "void" ) && ( argumentType.find( '*' ) == std::string::npos ) )
          {
            // the argument after stripping one pointer is just void
            assert( templateHeader.empty() );
            templateHeader = "    template <typename T>\n";

            size_t pos = argumentType.find( "void" );
            assert( pos != std::string::npos );
            argumentType.replace( pos, strlen( "void" ), "T" );
          }

          arguments += listedArgument ? ", " : "";
          arguments += "VULKAN_HPP_NAMESPACE::ArrayProxyNoTemporaries<" + argumentType + "> const & " + argumentName;
          if ( arrayListed )
          {
            arguments += " = {}";
          }
          listedArgument = true;
          arrayListed    = true;

          initializers += ( firstArgument ? ": " : ", " ) + mit->name + "( " + argumentName + ".data() )";
        }
        else
        {
          std::string argument = generateStructConstructorArgument( listedArgument, *mit, arrayListed );
          if ( !argument.empty() )
          {
            listedArgument = true;
            arguments += argument;
          }
          initializers += ( firstArgument ? ": " : ", " ) + mit->name + "( " + mit->name + "_ )";
        }
        firstArgument = false;
      }
    }

    auto pNextIt =
      std::find_if( structData.second.members.begin(), structData.second.members.end(), []( MemberData const & md ) { return md.name == "pNext"; } );
    if ( pNextIt != structData.second.members.end() )
    {
      // add pNext as a last optional argument to the constructor
      arguments += std::string( listedArgument ? ", " : "" ) + pNextIt->type.compose( "VULKAN_HPP_NAMESPACE" ) + " pNext_ = nullptr";
    }

    static const std::string constructorTemplate = R"(
#if !defined( VULKAN_HPP_DISABLE_ENHANCED_MODE )
${templateHeader}    ${structName}( ${arguments} )
    ${initializers}
    {${sizeChecks}}
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

    return replaceWithMap( constructorTemplate,
                           { { "arguments", arguments },
                             { "initializers", initializers },
                             { "sizeChecks", sizeChecks },
                             { "structName", stripPrefix( structData.first, "Vk" ) },
                             { "templateHeader", templateHeader } } );
  }
  return "";
}

std::string VulkanHppGenerator::generateStructConstructorArgument( bool listedArgument, MemberData const & memberData, bool withDefault ) const
{
  // skip members 'pNext' and members with a specified value, as they are never explicitly set
  std::string str;
  if ( ( memberData.name != "pNext" ) && memberData.value.empty() )
  {
    str += ( listedArgument ? ( ", " ) : "" );
    if ( memberData.arraySizes.empty() )
    {
      str += memberData.type.compose( "VULKAN_HPP_NAMESPACE" ) + " ";
    }
    else
    {
      str += generateStandardArray( memberData.type.compose( "VULKAN_HPP_NAMESPACE" ), memberData.arraySizes ) + " const & ";
    }
    str += memberData.name + "_";

    if ( withDefault )
    {
      str += " = ";
      auto enumIt = m_enums.find( memberData.type.type );
      if ( enumIt != m_enums.end() && memberData.type.postfix.empty() )
      {
        str += generateEnumInitializer( memberData.type, memberData.arraySizes, enumIt->second.values, enumIt->second.isBitmask );
      }
      else
      {
        assert( memberData.value.empty() );
        // all the rest can be initialized with just {}
        str += "{}";
      }
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateStructHashStructure( std::pair<std::string, StructureData> const & structure,
                                                             std::set<std::string> &                       listedStructs ) const
{
  assert( listedStructs.find( structure.first ) == listedStructs.end() );

  std::string str;
  for ( auto const & member : structure.second.members )
  {
    auto structIt = m_structures.find( member.type.type );
    if ( ( structIt != m_structures.end() ) && ( structure.first != member.type.type ) && ( listedStructs.find( member.type.type ) == listedStructs.end() ) )
    {
      str += generateStructHashStructure( *structIt, listedStructs );
    }
  }

  if ( !containsUnion( structure.first ) )
  {
    static const std::string hashTemplate = R"(
  ${enter}template <> struct hash<VULKAN_HPP_NAMESPACE::${structureType}>
  {
    std::size_t operator()(VULKAN_HPP_NAMESPACE::${structureType} const & ${structureName}) const VULKAN_HPP_NOEXCEPT
    {
      std::size_t seed = 0;
${hashSum}
      return seed;
    }
  };
${leave})";

    auto [enter, leave] = generateProtection( structure.first, m_structureAliasesInverse.find( structure.first ) != m_structureAliasesInverse.end() );

    std::string structureType = stripPrefix( structure.first, "Vk" );
    std::string structureName = startLowerCase( structureType );
    str += replaceWithMap( hashTemplate,
                           { { "enter", enter },
                             { "hashSum", generateStructHashSum( structureName, structure.second.members ) },
                             { "leave", leave },
                             { "structureName", structureName },
                             { "structureType", structureType } } );
  }

  listedStructs.insert( structure.first );
  return str;
}

std::string VulkanHppGenerator::generateStructHashStructures() const
{
  const std::string hashesTemplate = R"(
#if 14 <= VULKAN_HPP_CPP_VERSION
  //======================================
  //=== HASH structures for structures ===
  //======================================

#  if !defined( VULKAN_HPP_HASH_COMBINE )
#    define VULKAN_HPP_HASH_COMBINE( seed, value ) \
      seed ^= std::hash<std::decay<decltype( value )>::type>{}( value ) + 0x9e3779b9 + ( seed << 6 ) + ( seed >> 2 )
#  endif

${hashes}
#endif    // 14 <= VULKAN_HPP_CPP_VERSION
)";

  // Note reordering structs or handles by features and extensions is not possible!
  std::set<std::string> listedStructs;
  std::string           hashes;
  for ( auto const & structure : m_structures )
  {
    if ( listedStructs.find( structure.first ) == listedStructs.end() )
    {
      hashes += generateStructHashStructure( structure, listedStructs );
    }
  }
  return replaceWithMap( hashesTemplate, { { "hashes", hashes } } );
}

std::string VulkanHppGenerator::generateStructHashSum( std::string const & structName, std::vector<MemberData> const & members ) const
{
  std::string hashSum;
  for ( auto const & member : members )
  {
    if ( !member.arraySizes.empty() )
    {
      assert( member.arraySizes.size() < 3 );
      hashSum += "    for ( size_t i = 0; i < " + member.arraySizes[0] + "; ++i )\n";
      hashSum += "    {\n";
      if ( member.arraySizes.size() == 1 )
      {
        hashSum += "      VULKAN_HPP_HASH_COMBINE( seed, " + structName + "." + member.name + "[i] );\n";
      }
      else
      {
        hashSum += "      for ( size_t j=0; j < " + member.arraySizes[1] + "; ++j )\n";
        hashSum += "      {\n";
        hashSum += "        VULKAN_HPP_HASH_COMBINE( seed, " + structName + "." + member.name + "[i][j] );\n";
        hashSum += "      }\n";
      }
      hashSum += "    }\n";
    }
    else if ( member.type.type == "char" && !member.len.empty() )
    {
      assert( member.len.size() < 3 );
      if ( member.len.size() == 1 )
      {
        assert( member.len[0] == "null-terminated" );
        hashSum += "    for ( const char* p = " + structName + "." + member.name + "; *p != '\\0'; ++p )\n";
        hashSum += "    {\n";
        hashSum += "      VULKAN_HPP_HASH_COMBINE( seed, *p );\n";
        hashSum += "    }\n";
      }
      else
      {
        assert( member.len[1] == "null-terminated" );
        hashSum += "    for ( size_t i = 0; i < " + structName + "." + member.len[0] + "; ++i )\n";
        hashSum += "    {\n";
        hashSum += "        for ( const char* p = " + structName + "." + member.name + "[i]; *p != '\\0'; ++p )\n";
        hashSum += "        {\n";
        hashSum += "          VULKAN_HPP_HASH_COMBINE( seed, *p );\n";
        hashSum += "        }\n";
        hashSum += "    }\n";
      }
    }
    else
    {
      hashSum += "    VULKAN_HPP_HASH_COMBINE( seed, " + structName + "." + member.name + " );\n";
    }
  }
  assert( !hashSum.empty() );
  return hashSum.substr( 0, hashSum.size() - 1 );
}

std::string VulkanHppGenerator::generateStructs() const
{
  const std::string structsTemplate = R"(
  //===============
  //=== STRUCTS ===
  //===============

${structs}
)";

  // Note reordering structs or handles by features and extensions is not possible!
  std::set<std::string> listedStructs;
  std::string           structs;
  for ( auto const & structure : m_structures )
  {
    if ( listedStructs.find( structure.first ) == listedStructs.end() )
    {
      structs += generateStruct( structure, listedStructs );
    }
  }
  return replaceWithMap( structsTemplate, { { "structs", structs } } );
}

std::string VulkanHppGenerator::generateStructure( std::pair<std::string, StructureData> const & structure ) const
{
  auto [enter, leave] = generateProtection( structure.first, m_structureAliasesInverse.find( structure.first ) != m_structureAliasesInverse.end() );

  std::string str = "\n" + enter;

  std::string constructorAndSetters;
  constructorAndSetters += "#if !defined( VULKAN_HPP_NO_STRUCT_CONSTRUCTORS )";
  constructorAndSetters += generateStructConstructors( structure );
  constructorAndSetters += generateStructSubConstructor( structure );
  constructorAndSetters += "#endif /*VULKAN_HPP_NO_STRUCT_CONSTRUCTORS*/\n";
  constructorAndSetters += generateStructAssignmentOperators( structure );
  if ( !structure.second.returnedOnly )
  {
    // only structs that are not returnedOnly get setters!
    constructorAndSetters += "\n#if !defined( VULKAN_HPP_NO_STRUCT_SETTERS )";
    for ( size_t i = 0; i < structure.second.members.size(); i++ )
    {
      constructorAndSetters += generateStructSetter( stripPrefix( structure.first, "Vk" ), structure.second.members, i );
    }
    constructorAndSetters += "#endif /*VULKAN_HPP_NO_STRUCT_SETTERS*/\n";
  }

  std::string structureType = stripPrefix( structure.first, "Vk" );
  // the member variables
  std::string members, memberNames, memberTypes, sTypeValue;
  std::tie( members, memberNames, memberTypes, sTypeValue ) = generateStructMembers( structure );

  // reflect is meaningfull for structs only, filter out unions
  std::string reflect;
  if ( !structure.second.isUnion )
  {
    // use reflection only if VULKAN_HPP_USE_REFLECT is defined
    static const std::string reflectTemplate = R"(
#if defined( VULKAN_HPP_USE_REFLECT )
#if 14 <= VULKAN_HPP_CPP_VERSION
    auto
#else
    std::tuple<${memberTypes}>
#endif
      reflect() const VULKAN_HPP_NOEXCEPT
    {
      return std::tie( ${memberNames} );
    }
#endif
)";

    reflect = replaceWithMap( reflectTemplate, { { "memberNames", memberNames }, { "memberTypes", memberTypes } } );
  }

  // operator==() and operator!=()
  // only structs without a union as a member can have a meaningfull == and != operation; we filter them out
  std::string compareOperators;
  if ( !containsUnion( structure.first ) )
  {
    compareOperators += generateStructCompareOperators( structure );
  }

  static const std::string structureTemplate = R"(  struct ${structureType}
  {
    using NativeType = Vk${structureType};

${allowDuplicate}
${typeValue}
${constructorAndSetters}

    operator Vk${structureType} const &() const VULKAN_HPP_NOEXCEPT
    {
      return *reinterpret_cast<const Vk${structureType}*>( this );
    }

    operator Vk${structureType} &() VULKAN_HPP_NOEXCEPT
    {
      return *reinterpret_cast<Vk${structureType}*>( this );
    }
${reflect}
${compareOperators}
    public:
${members}
  };
)";

  std::string allowDuplicate, typeValue;
  if ( !sTypeValue.empty() )
  {
    allowDuplicate = std::string( "    static const bool allowDuplicate = " ) + ( structure.second.allowDuplicate ? "true;" : "false;" );
    typeValue      = "    static VULKAN_HPP_CONST_OR_CONSTEXPR StructureType structureType = StructureType::" + sTypeValue + ";\n";
  }
  str += replaceWithMap( structureTemplate,
                         { { "allowDuplicate", allowDuplicate },
                           { "constructorAndSetters", constructorAndSetters },
                           { "compareOperators", compareOperators },
                           { "members", members },
                           { "reflect", reflect },
                           { "structureType", structureType },
                           { "typeValue", typeValue } } );

  if ( !sTypeValue.empty() )
  {
    std::string cppTypeTemplate = R"(
  template <>
  struct CppType<StructureType, StructureType::${sTypeValue}>
  {
    using Type = ${structureType};
  };
)";
    str += replaceWithMap( cppTypeTemplate, { { "sTypeValue", sTypeValue }, { "structureType", structureType } } );
  }

  auto aliasIt = m_structureAliasesInverse.find( structure.first );
  if ( aliasIt != m_structureAliasesInverse.end() )
  {
    for ( std::string const & alias : aliasIt->second )
    {
      str += "  using " + stripPrefix( alias, "Vk" ) + " = " + structureType + ";\n";
    }
  }

  str += leave;
  return str;
}

std::string VulkanHppGenerator::generateStructExtendsStructs() const
{
  const std::string structExtendsTemplate = R"(
  //=======================
  //=== STRUCTS EXTENDS ===
  //=======================

${structExtends})";

  std::string           structExtends;
  std::set<std::string> listedStructs;
  for ( auto const & feature : m_features )
  {
    structExtends += generateStructExtendsStructs( feature.second.requireData, listedStructs, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    structExtends += generateStructExtendsStructs( extIt.second->second.requireData, listedStructs, extIt.second->first );
  }

  return replaceWithMap( structExtendsTemplate, { { "structExtends", structExtends } } );
}

std::string VulkanHppGenerator::generateStructExtendsStructs( std::vector<RequireData> const & requireData,
                                                              std::set<std::string> &          listedStructs,
                                                              std::string const &              title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto structIt = m_structures.find( type );
      if ( structIt != m_structures.end() )
      {
        assert( listedStructs.find( type ) == listedStructs.end() );
        listedStructs.insert( type );

        auto [enter, leave] = generateProtection( title, std::string() );

        // append all allowed structure chains
        for ( auto extendName : structIt->second.structExtends )
        {
          std::map<std::string, StructureData>::const_iterator itExtend = m_structures.find( extendName );
          if ( itExtend == m_structures.end() )
          {
            // look if the extendName acutally is an alias of some other structure
            auto aliasIt = m_structureAliases.find( extendName );
            if ( aliasIt != m_structureAliases.end() )
            {
              itExtend = m_structures.find( aliasIt->second.alias );
              assert( itExtend != m_structures.end() );
            }
          }

          auto [subEnter, subLeave] =
            generateProtection( itExtend->first, m_structureAliasesInverse.find( itExtend->first ) != m_structureAliasesInverse.end() );

          if ( enter != subEnter )
          {
            str += subEnter;
          }

          str += "  template <> struct StructExtends<" + stripPrefix( structIt->first, "Vk" ) + ", " + stripPrefix( extendName, "Vk" ) +
                 ">{ enum { value = true }; };\n";

          if ( leave != subLeave )
          {
            str += subLeave;
          }
        }
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::string VulkanHppGenerator::generateStructForwardDeclarations() const
{
  const std::string fowardDeclarationsTemplate = R"(
  //===================================
  //=== STRUCT forward declarations ===
  //===================================

${forwardDeclarations}
)";

  std::string forwardDeclarations;
  for ( auto const & feature : m_features )
  {
    forwardDeclarations += generateStructForwardDeclarations( feature.second.requireData, feature.first );
  }
  for ( auto const & extIt : m_extensionsByNumber )
  {
    forwardDeclarations += generateStructForwardDeclarations( extIt.second->second.requireData, extIt.second->first );
  }

  return replaceWithMap( fowardDeclarationsTemplate, { { "forwardDeclarations", forwardDeclarations } } );
}

std::string VulkanHppGenerator::generateStructForwardDeclarations( std::vector<RequireData> const & requireData, std::string const & title ) const
{
  std::string str;
  for ( auto const & require : requireData )
  {
    for ( auto const & type : require.types )
    {
      auto structIt = m_structures.find( type );
      if ( structIt != m_structures.end() )
      {
        std::string structureType = stripPrefix( structIt->first, "Vk" );
        str += ( structIt->second.isUnion ? "  union " : "  struct " ) + structureType + ";\n";
        auto inverseIt = m_structureAliasesInverse.find( type );
        if ( inverseIt != m_structureAliasesInverse.end() )
        {
          for ( auto alias : inverseIt->second )
          {
            str += "  using " + stripPrefix( alias, "Vk" ) + " = " + structureType + ";\n";
          }
        }
      }
    }
  }
  return addTitleAndProtection( title, str );
}

std::tuple<std::string, std::string, std::string, std::string>
  VulkanHppGenerator::generateStructMembers( std::pair<std::string, StructureData> const & structData ) const
{
  std::string members, memberNames, memberTypes, sTypeValue;
  for ( auto const & member : structData.second.members )
  {
    members += "    ";
    std::string type;
    if ( !member.bitCount.empty() && member.type.type.starts_with( "Vk" ) )
    {
      assert( member.type.prefix.empty() && member.type.postfix.empty() );  // never encounterd a different case
      type = member.type.type;
    }
    else if ( member.arraySizes.empty() )
    {
      type = member.type.compose( "VULKAN_HPP_NAMESPACE" );
    }
    else
    {
      assert( member.type.prefix.empty() && member.type.postfix.empty() );
      type = generateStandardArrayWrapper( member.type.compose( "VULKAN_HPP_NAMESPACE" ), member.arraySizes );
    }
    members += type + " " + member.name;
    if ( !member.value.empty() )
    {
      // special handling for members with legal value: use it as the default
      members += " = ";
      if ( member.type.type == "uint32_t" )
      {
        members += member.value;
      }
      else
      {
        auto enumIt = m_enums.find( member.type.type );
        assert( enumIt != m_enums.end() );
        std::string enumValue = member.value;
        auto        valueIt   = std::find_if(
          enumIt->second.values.begin(), enumIt->second.values.end(), [&enumValue]( EnumValueData const & evd ) { return enumValue == evd.name; } );
        assert( valueIt != enumIt->second.values.end() );
        std::string valueName = generateEnumValueName( enumIt->first, valueIt->name, enumIt->second.isBitmask, m_tags );
        members += stripPrefix( member.type.type, "Vk" ) + "::" + valueName;
        if ( member.name == "sType" )
        {
          sTypeValue = valueName;
        }
      }
    }
    else
    {
      // as we don't have any meaningful default initialization values, everything can be initialized by just '{}'
      // !
      assert( member.arraySizes.empty() || member.bitCount.empty() );
      if ( !member.bitCount.empty() )
      {
        members += " : " + member.bitCount;  // except for bitfield members, where no default member initializatin
                                             // is supported (up to C++20)
      }
      else
      {
        members += " = ";
        auto enumIt = m_enums.find( member.type.type );
        if ( member.arraySizes.empty() && ( enumIt != m_enums.end() ) && member.type.postfix.empty() )
        {
          members += generateEnumInitializer( member.type, member.arraySizes, enumIt->second.values, enumIt->second.isBitmask );
        }
        else
        {
          members += "{}";
        }
      }
    }
    members += ";\n";

    memberNames += member.name + ", ";
    memberTypes += type + " const &, ";
  }
  return std::make_tuple( members, stripPostfix( memberNames, ", " ), stripPostfix( memberTypes, ", " ), sTypeValue );
}

std::string VulkanHppGenerator::generateStructSetter( std::string const & structureName, std::vector<MemberData> const & memberData, size_t index ) const
{
  std::string        str;
  MemberData const & member = memberData[index];
  if ( member.type.type != "VkStructureType" )  // filter out StructureType, which is supposed to be immutable !
  {
    static const std::string templateString = R"(
    ${constexpr}${structureName} & set${MemberName}( ${memberType} ${reference}${memberName}_ ) VULKAN_HPP_NOEXCEPT
    {
      ${assignment};
      return *this;
    }
)";

    std::string memberType         = member.arraySizes.empty() ? member.type.compose( "VULKAN_HPP_NAMESPACE" )
                                                               : generateStandardArray( member.type.compose( "VULKAN_HPP_NAMESPACE" ), member.arraySizes );
    bool        isReinterpretation = !member.bitCount.empty() && member.type.type.starts_with( "Vk" );
    std::string assignment;
    if ( isReinterpretation )
    {
      assignment = member.name + " = " + "*reinterpret_cast<" + member.type.type + "*>(&" + member.name + "_)";
    }
    else
    {
      assignment = member.name + " = " + member.name + "_";
    }

    str +=
      replaceWithMap( templateString,
                      { { "assignment", assignment },
                        { "constexpr", isReinterpretation ? "" : "VULKAN_HPP_CONSTEXPR_14 " },
                        { "memberName", member.name },
                        { "MemberName", startUpperCase( member.name ) },
                        { "memberType", memberType },
                        { "reference", ( member.type.postfix.empty() && ( m_structures.find( member.type.type ) != m_structures.end() ) ) ? "const & " : "" },
                        { "structureName", structureName } } );

    if ( !member.len.empty() && ( member.len[0] != "null-terminated" ) &&
         ( ( altLens.find( member.len[0] ) == altLens.end() ) || ( member.len[0] == "codeSize / 4" ) ) )
    {
      assert( member.name.front() == 'p' );
      std::string arrayName = startLowerCase( stripPrefix( member.name, "p" ) );

      std::string lenName, lenValue;
      if ( member.len[0] == "codeSize / 4" )
      {
        lenName  = "codeSize";
        lenValue = arrayName + "_.size() * 4";
      }
      else
      {
        lenName  = member.len[0];
        lenValue = arrayName + "_.size()";
      }

      assert( memberType.back() == '*' );
      memberType = trimEnd( stripPostfix( memberType, "*" ) );

      std::string templateHeader;
      if ( ( member.type.type == "void" ) && ( memberType.find( '*' ) == std::string::npos ) )
      {
        assert( templateHeader.empty() );
        templateHeader = "template <typename T>\n    ";

        size_t pos = memberType.find( "void" );
        assert( pos != std::string::npos );
        memberType.replace( pos, strlen( "void" ), "T" );

        lenValue += " * sizeof(T)";
      }

      auto lenMember = findStructMemberIt( lenName, memberData );
      assert( lenMember != memberData.end() && lenMember->type.prefix.empty() && lenMember->type.postfix.empty() );
      if ( lenMember->type.type != "size_t" )
      {
        lenValue = "static_cast<" + lenMember->type.type + ">( " + lenValue + " )";
      }

      static const std::string setArrayTemplate = R"(
#if !defined( VULKAN_HPP_DISABLE_ENHANCED_MODE )
    ${templateHeader}${structureName} & set${ArrayName}( VULKAN_HPP_NAMESPACE::ArrayProxyNoTemporaries<${memberType}> const & ${arrayName}_ ) VULKAN_HPP_NOEXCEPT
    {
      ${lenName} = ${lenValue};
      ${memberName} = ${arrayName}_.data();
      return *this;
    }
#endif /*VULKAN_HPP_DISABLE_ENHANCED_MODE*/
)";

      str += replaceWithMap( setArrayTemplate,
                             { { "arrayName", arrayName },
                               { "ArrayName", startUpperCase( arrayName ) },
                               { "lenName", lenName },
                               { "lenValue", lenValue },
                               { "memberName", member.name },
                               { "memberType", memberType },
                               { "structureName", structureName },
                               { "templateHeader", templateHeader } } );
    }
  }
  return str;
}

std::string VulkanHppGenerator::generateStructSubConstructor( std::pair<std::string, StructureData> const & structData ) const
{
  if ( !structData.second.subStruct.empty() )
  {
    auto const & subStruct = m_structures.find( structData.second.subStruct );
    assert( subStruct != m_structures.end() );

    std::string subStructArgumentName = startLowerCase( stripPrefix( subStruct->first, "Vk" ) );

    std::string subCopies;
    bool        firstArgument = true;
    for ( size_t i = 0; i < subStruct->second.members.size(); i++ )
    {
      assert( structData.second.members[i].arraySizes.empty() );
      static const std::string subCopiesTemplate =
        R"(      ${separator} ${structMemberName}( ${subStructArgumentName}.${subStructMemberName} )
)";
      subCopies += replaceWithMap( subCopiesTemplate,
                                   { { "separator", firstArgument ? ":" : "," },
                                     { "structMemberName", structData.second.members[i].name },
                                     { "subStructMemberName", subStruct->second.members[i].name },
                                     { "subStructArgumentName", subStructArgumentName } } );
      firstArgument = false;
    }

    std::string subArguments;
    bool        listedArgument = true;
    for ( size_t i = subStruct->second.members.size(); i < structData.second.members.size(); i++ )
    {
      std::string argument = generateStructConstructorArgument( listedArgument, structData.second.members[i], true );
      if ( !argument.empty() )
      {
        listedArgument = true;
        subArguments += argument;
      }

      assert( structData.second.members[i].arraySizes.empty() );
      static const std::string subCopiesTemplate = R"(    , ${memberName}( ${memberName}_ )
)";
      subCopies += replaceWithMap( subCopiesTemplate, { { "memberName", structData.second.members[i].name } } );
    }

    static const std::string subStructConstructorTemplate = R"(
    explicit ${structName}( ${subStructName} const & ${subStructArgumentName}${subArguments} )
${subCopies}    {}
)";
    return replaceWithMap( subStructConstructorTemplate,
                           { { "structName", stripPrefix( structData.first, "Vk" ) },
                             { "subArguments", subArguments },
                             { "subCopies", subCopies },
                             { "subStructArgumentName", subStructArgumentName },
                             { "subStructName", stripPrefix( subStruct->first, "Vk" ) } } );
  }
  return "";
}

std::string VulkanHppGenerator::generateSuccessCheck( std::vector<std::string> const & successCodes ) const
{
  assert( !successCodes.empty() );
  std::string successCheck = "result == " + generateSuccessCode( successCodes[0], m_tags );
  if ( 1 < successCodes.size() )
  {
    successCheck = "( " + successCheck + " )";
    for ( size_t i = 1; i < successCodes.size(); ++i )
    {
      successCheck += "|| ( result == " + generateSuccessCode( successCodes[i], m_tags ) + " )";
    }
  }
  return successCheck;
}

std::string VulkanHppGenerator::generateSuccessCodeList( std::vector<std::string> const & successCodes, bool enumerating ) const
{
  std::string successCodeList;
  if ( ( 1 < successCodes.size() ) && !enumerating )
  {
    successCodeList = ", { " + generateSuccessCode( successCodes[0], m_tags );
    for ( size_t i = 1; i < successCodes.size(); ++i )
    {
      successCodeList += ", " + generateSuccessCode( successCodes[i], m_tags );
    }
    successCodeList += " }";
  }
  return successCodeList;
}

std::string VulkanHppGenerator::generateThrowResultException() const
{
  auto enumIt = m_enums.find( "VkResult" );

  std::string cases;
  for ( auto const & value : enumIt->second.values )
  {
    if ( value.name.starts_with( "VK_ERROR" ) )
    {
      auto [enter, leave]   = generateProtection( value.extension, value.protect );
      std::string valueName = generateEnumValueName( enumIt->first, value.name, false, m_tags );
      cases += enter + "      case Result::" + valueName + ": throw " + stripPrefix( valueName, "eError" ) + "Error( message );\n" + leave;
    }
  }
  cases.pop_back();  // remove last newline

  const std::string throwTemplate = R"(
  namespace
  {
    [[noreturn]] void throwResultException( Result result, char const * message )
    {
      switch ( result )
      {
${cases}
        default: throw SystemError( make_error_code( result ) );
      }
    }
  })";
  return replaceWithMap( throwTemplate, { { "cases", cases } } );
}

std::string VulkanHppGenerator::generateTypenameCheck( std::vector<size_t> const &               returnParams,
                                                       std::map<size_t, VectorParamData> const & vectorParams,
                                                       bool                                      definition,
                                                       std::vector<std::string> const &          dataTypes,
                                                       bool                                      singular,
                                                       bool                                      withAllocator,
                                                       bool                                      unique,
                                                       bool                                      chained ) const
{
  std::string typenameCheck, enableIf;
  if ( !singular && withAllocator )
  {
    for ( size_t i = 0; i < returnParams.size(); ++i )
    {
      if ( vectorParams.find( returnParams[i] ) != vectorParams.end() )
      {
        std::string elementType         = chained ? "StructureChain" : stripPrefix( dataTypes[i], "VULKAN_HPP_NAMESPACE::" );
        std::string extendedElementType = elementType;
        if ( unique )
        {
          extendedElementType = "UniqueHandle<" + elementType + ", Dispatch>";
        }
        std::string index = std::to_string( i );
        if ( definition )
        {
          typenameCheck += ", typename B" + index;
        }
        else
        {
          typenameCheck += ", typename B" + index + " = " + startUpperCase( elementType ) + "Allocator";
        }
        enableIf += enableIf.empty() ? ", typename std::enable_if<" : " && ";
        enableIf += "std::is_same<typename B" + index + "::value_type, " + extendedElementType + ">::value";
      }
    }
    assert( !typenameCheck.empty() );
    if ( !typenameCheck.empty() )
    {
      typenameCheck += enableIf + ", int>::type";
      if ( !definition )
      {
        typenameCheck += " = 0";
      }
    }
  }
  return typenameCheck;
}

std::string VulkanHppGenerator::generateUnion( std::pair<std::string, StructureData> const & structure ) const
{
  auto [enter, leave]   = generateProtection( structure.first, m_structureAliasesInverse.find( structure.first ) != m_structureAliasesInverse.end() );
  std::string unionName = stripPrefix( structure.first, "Vk" );

  bool               firstMember = true;
  std::set<TypeInfo> listedTypes;  // create just one constructor per different type !
  std::string        constructors;
  for ( auto memberIt = structure.second.members.begin(); memberIt != structure.second.members.end(); ++memberIt )
  {
    if ( listedTypes.insert( memberIt->type ).second )
    {
      // VkBool32 is aliased to uint32_t. Don't create a VkBool32 constructor if the union also contains a
      // uint32_t constructor.
      if ( memberIt->type.type == "VkBool32" )
      {
        if ( findStructMemberItByType( "uint32_t", structure.second.members ) != structure.second.members.end() )
        {
          continue;
        }
      }

      bool multipleType =
        ( std::find_if( std::next( memberIt ),
                        structure.second.members.end(),
                        [memberIt]( MemberData const & member ) { return member.type == memberIt->type; } ) != structure.second.members.end() );
      std::string memberType = ( memberIt->arraySizes.empty() )
                               ? memberIt->type.compose( "VULKAN_HPP_NAMESPACE" )
                               : ( "const " + generateStandardArray( memberIt->type.compose( "VULKAN_HPP_NAMESPACE" ), memberIt->arraySizes ) + "&" );

      // In a majority of cases this can be constexpr in C++11 as well, however, determining when exactly
      // that is the case is a lot more involved and probably not worth it.
      static const std::string constructorTemplate = R"(
    VULKAN_HPP_CONSTEXPR_14 ${unionName}( ${memberType} ${argumentName}_${defaultAssignment} )
      : ${memberName}( ${argumentName}_ )
    {})";

      constructors += ( firstMember ? "" : "\n" ) + replaceWithMap( constructorTemplate,
                                                                    { { "argumentName", multipleType ? generateName( memberIt->type ) : memberIt->name },
                                                                      { "defaultAssignment", firstMember ? " = {}" : "" },
                                                                      { "memberName", memberIt->name },
                                                                      { "memberType", memberType },
                                                                      { "unionName", stripPrefix( structure.first, "Vk" ) } } );
      firstMember = false;
    }
  }

  // one setter per union element
  std::string setters;
  for ( size_t i = 0; i < structure.second.members.size(); i++ )
  {
    setters += generateStructSetter( stripPrefix( structure.first, "Vk" ), structure.second.members, i );
  }
  // filter out leading and trailing newline
  setters = setters.substr( 1, setters.length() - 2 );

  // the union member variables
  std::string members;
  // if there's at least one Vk... type in this union, check for unrestricted unions support
  bool needsUnrestrictedUnions =
    ( std::find_if( structure.second.members.begin(),
                    structure.second.members.end(),
                    []( MemberData const & member ) { return member.type.type.starts_with( "Vk" ); } ) != structure.second.members.end() );
  if ( needsUnrestrictedUnions )
  {
    members += "#ifdef VULKAN_HPP_HAS_UNRESTRICTED_UNIONS\n";
  }
  for ( auto const & member : structure.second.members )
  {
    static const std::string memberTemplate = R"(    ${memberType} ${memberName};
)";
    members +=
      replaceWithMap( memberTemplate,
                      { { "memberName", member.name },
                        { "memberType",
                          member.arraySizes.empty() ? member.type.compose( "VULKAN_HPP_NAMESPACE" )
                                                    : generateStandardArrayWrapper( member.type.compose( "VULKAN_HPP_NAMESPACE" ), member.arraySizes ) } } );
  }
  if ( needsUnrestrictedUnions )
  {
    members += "#else\n";
    for ( auto const & member : structure.second.members )
    {
      static const std::string memberTemplate = R"(    ${memberType} ${memberName}${arraySizes};
)";
      members += replaceWithMap(
        memberTemplate,
        { { "arraySizes", generateCArraySizes( member.arraySizes ) }, { "memberName", member.name }, { "memberType", member.type.compose( "" ) } } );
    }
    members += "#endif  /*VULKAN_HPP_HAS_UNRESTRICTED_UNIONS*/\n";
  }

  static const std::string unionTemplate = R"(
${enter}  union ${unionName}
  {
    using NativeType = Vk${unionName};
#if !defined( VULKAN_HPP_NO_UNION_CONSTRUCTORS )
${constructors}
#endif /*VULKAN_HPP_NO_UNION_CONSTRUCTORS*/

#if !defined( VULKAN_HPP_NO_UNION_SETTERS )
${setters}
#endif /*VULKAN_HPP_NO_UNION_SETTERS*/

    operator Vk${unionName} const &() const
    {
      return *reinterpret_cast<const Vk${unionName}*>( this );
    }

    operator Vk${unionName} &()
    {
      return *reinterpret_cast<Vk${unionName}*>( this );
    }

${members}
  };
${leave})";

  return replaceWithMap(
    unionTemplate,
    { { "constructors", constructors }, { "enter", enter }, { "leave", leave }, { "members", members }, { "setters", setters }, { "unionName", unionName } } );
}

std::string VulkanHppGenerator::generateUniqueTypes( std::string const & parentType, std::set<std::string> const & childrenTypes ) const
{
  std::string childrenTraits;
  for ( auto const & childType : childrenTypes )
  {
    auto handleIt = m_handles.find( childType );
    assert( handleIt != m_handles.end() );

    std::string type = stripPrefix( childType, "Vk" );

    auto [enter, leave] = generateProtection( handleIt->first, !handleIt->second.alias.empty() );

    std::string aliasHandle;
    if ( !handleIt->second.alias.empty() )
    {
      static const std::string aliasHandleTemplate =
        R"(  using Unique${aliasType} = UniqueHandle<${type}, VULKAN_HPP_DEFAULT_DISPATCHER_TYPE>;
)";

      aliasHandle += replaceWithMap( aliasHandleTemplate, { { "aliasType", stripPrefix( handleIt->second.alias, "Vk" ) }, { "type", type } } );
    }

    static const std::string traitsTemplate = R"(${enter}  template <typename Dispatch>
  class UniqueHandleTraits<${type}, Dispatch>
  {
  public:
    using deleter = ${deleterType}${deleterAction}<${deleterParent}${deleterPool}, Dispatch>;
  };
  using Unique${type} = UniqueHandle<${type}, VULKAN_HPP_DEFAULT_DISPATCHER_TYPE>;
${aliasHandle}${leave})";

    childrenTraits += replaceWithMap( traitsTemplate,
                                      { { "aliasHandle", aliasHandle },
                                        { "deleterAction", ( handleIt->second.deleteCommand.substr( 2, 4 ) == "Free" ) ? "Free" : "Destroy" },
                                        { "deleterParent", parentType.empty() ? "NoParent" : stripPrefix( parentType, "Vk" ) },
                                        { "deleterPool", handleIt->second.deletePool.empty() ? "" : ", " + stripPrefix( handleIt->second.deletePool, "Vk" ) },
                                        { "deleterType", handleIt->second.deletePool.empty() ? "Object" : "Pool" },
                                        { "enter", enter },
                                        { "leave", leave },
                                        { "type", type } } );
  }

  static const std::string uniqueTypeTemplate = R"(
#ifndef VULKAN_HPP_NO_SMART_HANDLE
${parentClass}${childrenTraits}#endif /*VULKAN_HPP_NO_SMART_HANDLE*/
)";

  return replaceWithMap(
    uniqueTypeTemplate,
    { { "childrenTraits", childrenTraits }, { "parentClass", parentType.empty() ? "" : ( "  class " + stripPrefix( parentType, "Vk" ) + ";\n" ) } } );
}

std::string VulkanHppGenerator::generateVectorSizeCheck( std::string const &                           name,
                                                         CommandData const &                           commandData,
                                                         size_t                                        initialSkipCount,
                                                         std::map<size_t, std::vector<size_t>> const & countToVectorMap,
                                                         std::set<size_t> const &                      skippedParams,
                                                         bool                                          onlyThrows ) const
{
  std::string const assertTemplate = "    VULKAN_HPP_ASSERT( ${zeroSizeCheck}${firstVectorName}.size() == ${secondVectorName}.size() );";
  std::string const assertTemplateVoid =
    "    VULKAN_HPP_ASSERT( ${zeroSizeCheck}${firstVectorName}.size() * sizeof( ${firstDataType} ) == ${secondVectorName}.size() * sizeof( ${secondDataType} ) );";
  std::string const assertTemplateByLen = "    VULKAN_HPP_ASSERT( ${vectorName}.size() == ${sizeValue} );";
  std::string const throwTemplate =
    R"#(    if ( ${zeroSizeCheck}${firstVectorName}.size() != ${secondVectorName}.size() )
  {
    throw LogicError( VULKAN_HPP_NAMESPACE_STRING "::${className}::${commandName}: ${firstVectorName}.size() != ${secondVectorName}.size()" );
  })#";
  std::string const throwTemplateVoid =
    R"#(    if ( ${zeroSizeCheck}${firstVectorName}.size() * sizeof( ${firstDataType} ) != ${secondVectorName}.size() * sizeof( ${secondDataType} ) )
  {
    throw LogicError( VULKAN_HPP_NAMESPACE_STRING "::${className}::${commandName}: ${firstVectorName}.size() * sizeof( ${firstDataType} ) != ${secondVectorName}.size() * sizeof( ${secondDataType} )" );
  })#";
  std::string const throwTemplateByLen = R"#(    if ( ${vectorName}.size() != ${sizeValue} )
    {
      throw LogicError( VULKAN_HPP_NAMESPACE_STRING "::${className}::${commandName}: ${vectorName}.size() != ${sizeValue}" );
    })#";

  std::string className   = stripPrefix( commandData.params[initialSkipCount - 1].type.type, "Vk" );
  std::string commandName = generateCommandName( name, commandData.params, initialSkipCount, m_tags, false, false );

  std::string assertions, throws;
  for ( auto const & cvm : countToVectorMap )
  {
    size_t      defaultStartIndex = determineDefaultStartIndex( commandData.params, skippedParams );
    std::string firstVectorName   = startLowerCase( stripPrefix( commandData.params[cvm.second[0]].name, "p" ) );

    if ( cvm.second.size() == 1 )
    {
      assert( isLenByStructMember( commandData.params[cvm.second[0]].len, commandData.params[cvm.first] ) );

      std::vector<std::string> lenParts = tokenize( commandData.params[cvm.second[0]].len, "->" );
      assert( lenParts.size() == 2 );
      std::string sizeValue = startLowerCase( stripPrefix( lenParts[0], "p" ) ) + "." + lenParts[1];
      assertions += replaceWithMap( assertTemplateByLen, { { "sizeValue", sizeValue }, { "vectorName", firstVectorName } } );
      throws += replaceWithMap( throwTemplateByLen,
                                { { "className", className }, { "commandName", commandName }, { "sizeValue", sizeValue }, { "vectorName", firstVectorName } } );
    }
    else
    {
      for ( size_t i = 1; i < cvm.second.size(); i++ )
      {
        std::string secondVectorName  = startLowerCase( stripPrefix( commandData.params[cvm.second[i]].name, "p" ) );
        bool        withZeroSizeCheck = commandData.params[cvm.second[i]].optional && ( defaultStartIndex <= cvm.second[i] );
        if ( commandData.params[cvm.second[0]].type.type == "void" )
        {
          assert( commandData.params[cvm.second[i]].type.type == "void" );
          std::string firstDataType  = stripPrefix( commandData.params[cvm.second[0]].name, "p" ) + "Type";
          std::string secondDataType = stripPrefix( commandData.params[cvm.second[i]].name, "p" ) + "Type";
          assertions += replaceWithMap( assertTemplateVoid,
                                        { { "firstDataType", firstDataType },
                                          { "firstVectorName", firstVectorName },
                                          { "secondDataType", secondDataType },
                                          { "secondVectorName", secondVectorName },
                                          { "zeroSizeCheck", withZeroSizeCheck ? ( secondVectorName + ".empty() || " ) : "" } } );
          throws += replaceWithMap( throwTemplateVoid,
                                    { { "firstDataType", firstDataType },
                                      { "firstVectorName", firstVectorName },
                                      { "className", className },
                                      { "commandName", commandName },
                                      { "secondDataType", secondDataType },
                                      { "secondVectorName", secondVectorName },
                                      { "zeroSizeCheck", withZeroSizeCheck ? ( "!" + secondVectorName + ".empty() && " ) : "" } } );
        }
        else
        {
          assertions += replaceWithMap( assertTemplate,
                                        { { "firstVectorName", firstVectorName },
                                          { "secondVectorName", secondVectorName },
                                          { "zeroSizeCheck", withZeroSizeCheck ? ( secondVectorName + ".empty() || " ) : "" } } );
          throws += replaceWithMap( throwTemplate,
                                    { { "firstVectorName", firstVectorName },
                                      { "className", className },
                                      { "commandName", commandName },
                                      { "secondVectorName", secondVectorName },
                                      { "zeroSizeCheck", withZeroSizeCheck ? ( "!" + secondVectorName + ".empty() && " ) : "" } } );
        }
        if ( i + 1 < cvm.second.size() )
        {
          assertions += "\n";
          throws += "\n";
        }
      }
    }
  }

  std::string const sizeCheckTemplate =
    R"(#ifdef VULKAN_HPP_NO_EXCEPTIONS
${assertions}
#else
${throws}
#endif  /*VULKAN_HPP_NO_EXCEPTIONS*/)";

  return onlyThrows ? throws : replaceWithMap( sizeCheckTemplate, { { "assertions", assertions }, { "throws", throws } } );
}

std::pair<std::string, std::string> VulkanHppGenerator::getParentTypeAndName( std::pair<std::string, HandleData> const & handle ) const
{
  std::string parentType, parentName;
  if ( handle.first == "VkInstance" )
  {
    parentType = "Context";
    parentName = "context";
  }
  else
  {
    bool skip = skipLeadingGrandParent( handle );
    assert( !handle.second.constructorIts.empty() && ( ( skip ? 1u : 0u ) < handle.second.constructorIts.front()->second.params.size() ) );
    auto const & param = handle.second.constructorIts.front()->second.params[skip ? 1 : 0];
    assert( isHandleType( param.type.type ) && param.type.isValue() );
    parentType = stripPrefix( param.type.type, "Vk" );
    parentName = param.name;
  }
  return std::make_pair( parentType, parentName );
}

std::string VulkanHppGenerator::getPlatform( std::string const & title ) const
{
  if ( m_features.find( title ) == m_features.end() )
  {
    auto extensionIt = m_extensions.find( title );
    assert( extensionIt != m_extensions.end() );
    return extensionIt->second.platform;
  }
  return "";
}

std::pair<std::string, std::string> VulkanHppGenerator::getPoolTypeAndName( std::string const & type ) const
{
  auto structIt = m_structures.find( type );
  assert( structIt != m_structures.end() );
  auto memberIt = std::find_if(
    structIt->second.members.begin(), structIt->second.members.end(), []( MemberData const & md ) { return md.name.find( "Pool" ) != std::string::npos; } );
  assert( memberIt != structIt->second.members.end() );
  assert( std::find_if( std::next( memberIt ),
                        structIt->second.members.end(),
                        []( MemberData const & md ) { return md.name.find( "Pool" ) != std::string::npos; } ) == structIt->second.members.end() );
  return std::make_pair( memberIt->type.type, memberIt->name );
}

std::string VulkanHppGenerator::getVectorSize( std::vector<ParamData> const &            params,
                                               std::map<size_t, VectorParamData> const & vectorParams,
                                               size_t                                    returnParam,
                                               std::string const &                       returnParamType,
                                               std::set<size_t> const &                  templatedParams ) const
{
  std::string              vectorSize;
  std::vector<std::string> lenParts = tokenize( params[returnParam].len, "->" );
  switch ( lenParts.size() )
  {
    case 1:
      {
        std::string const & len = lenParts[0];
        size_t              lenIdx =
          std::distance( params.begin(), std::find_if( params.begin(), params.end(), [&len]( ParamData const & pd ) { return pd.name == len; } ) );
        assert( lenIdx < params.size() );
        // look for the len, not being the len of the return param, but of an other vector param
        auto lenVectorParamIt =
          std::find_if( vectorParams.begin(),
                        vectorParams.end(),
                        [&lenIdx, &returnParam]( auto const & vpi ) { return ( vpi.first != returnParam ) && ( vpi.second.lenParam == lenIdx ); } );
        if ( lenVectorParamIt == vectorParams.end() )
        {
          vectorSize = lenParts[0];
          if ( templatedParams.find( returnParam ) != templatedParams.end() )
          {
            vectorSize += " / sizeof( " + returnParamType + " )";
          }
        }
        else
        {
          assert( templatedParams.find( returnParam ) == templatedParams.end() );
          vectorSize = startLowerCase( stripPrefix( params[lenVectorParamIt->first].name, "p" ) ) + ".size()";
        }
      }
      break;
    case 2:
      assert( vectorParams.find( returnParam ) != vectorParams.end() );
      vectorSize = startLowerCase( stripPrefix( lenParts[0], "p" ) ) + "." + lenParts[1];
      break;
    default: assert( false ); break;
  }
  assert( !vectorSize.empty() );
  return vectorSize;
}

bool VulkanHppGenerator::hasParentHandle( std::string const & handle, std::string const & parent ) const
{
  std::string candidate = handle;
  while ( !candidate.empty() )
  {
    auto const & handleIt = m_handles.find( candidate );
    assert( handleIt != m_handles.end() );
    if ( handleIt->second.parent == parent )
    {
      return true;
    }
    else
    {
      candidate = handleIt->second.parent;
    }
  }
  return false;
}

bool VulkanHppGenerator::isDeviceCommand( CommandData const & commandData ) const
{
  return !commandData.handle.empty() && !commandData.params.empty() && ( m_handles.find( commandData.params[0].type.type ) != m_handles.end() ) &&
         ( commandData.params[0].type.type != "VkInstance" ) && ( commandData.params[0].type.type != "VkPhysicalDevice" );
}

bool VulkanHppGenerator::isHandleType( std::string const & type ) const
{
  if ( type.starts_with( "Vk" ) )
  {
    auto it = m_handles.find( type );
    if ( it == m_handles.end() )
    {
      it = std::find_if( m_handles.begin(), m_handles.end(), [&type]( std::pair<std::string, HandleData> const & hd ) { return hd.second.alias == type; } );
    }
    return ( it != m_handles.end() );
  }
  return false;
}

bool VulkanHppGenerator::isLenByStructMember( std::string const & name, std::vector<ParamData> const & params ) const
{
  // check if name specifies a member of a struct
  std::vector<std::string> nameParts = tokenize( name, "->" );
  if ( nameParts.size() == 1 )
  {
    // older versions of vk.xml used the notation parameter::member
    nameParts = tokenize( name, "::" );
  }
  if ( nameParts.size() == 2 )
  {
    auto paramIt = std::find_if( params.begin(), params.end(), [&n = nameParts[0]]( ParamData const & pd ) { return pd.name == n; } );
    if ( paramIt != params.end() )
    {
#if !defined( NDEBUG )
      auto structureIt = m_structures.find( paramIt->type.type );
      assert( structureIt != m_structures.end() );
      assert( isStructMember( nameParts[1], structureIt->second.members ) );
#endif
      return true;
    }
  }
  return false;
}

bool VulkanHppGenerator::isLenByStructMember( std::string const & name, ParamData const & param ) const
{
  // check if name specifies a member of a struct
  std::vector<std::string> nameParts = tokenize( name, "->" );
  if ( nameParts.size() == 1 )
  {
    // older versions of vk.xml used the notation parameter::member
    nameParts = tokenize( name, "::" );
  }
  if ( ( nameParts.size() == 2 ) && ( nameParts[0] == param.name ) )
  {
#if !defined( NDEBUG )
    auto structureIt = m_structures.find( param.type.type );
    assert( structureIt != m_structures.end() );
    assert( isStructMember( nameParts[1], structureIt->second.members ) );
#endif
    return true;
  }
  return false;
}

bool VulkanHppGenerator::isMultiSuccessCodeConstructor( std::vector<std::map<std::string, CommandData>::const_iterator> const & constructorIts ) const
{
  bool ok = !constructorIts.empty();
  if ( ok )
  {
    auto constructorIt = constructorIts.begin();
    ok                 = ( 2 < ( *constructorIt )->second.successCodes.size() ) ||
         ( ( ( *constructorIt )->second.successCodes.size() == 2 ) && ( ( *constructorIt )->second.successCodes[1] != "VK_INCOMPLETE" ) );
#if !defined( NDEBUG )
    for ( constructorIt = std::next( constructorIt ); constructorIt != constructorIts.end(); ++constructorIt )
    {
      assert( ok == ( 2 < ( *constructorIt )->second.successCodes.size() ) ||
              ( ( ( *constructorIt )->second.successCodes.size() == 2 ) && ( ( *constructorIt )->second.successCodes[1] != "VK_INCOMPLETE" ) ) );
    }
#endif
  }
  return ok;
}

bool VulkanHppGenerator::isParam( std::string const & name, std::vector<ParamData> const & params ) const
{
  return std::find_if( params.begin(), params.end(), [&name]( ParamData const & pd ) { return pd.name == name; } ) != params.end();
}

bool VulkanHppGenerator::isStructMember( std::string const & name, std::vector<MemberData> const & memberData ) const
{
  return findStructMemberIt( name, memberData ) != memberData.end();
}

bool VulkanHppGenerator::isStructureChainAnchor( std::string const & type ) const
{
  if ( type.starts_with( "Vk" ) )
  {
    auto it = m_structures.find( type );
    if ( it == m_structures.end() )
    {
      auto aliasIt = m_structureAliases.find( type );
      if ( aliasIt != m_structureAliases.end() )
      {
        it = m_structures.find( aliasIt->second.alias );
      }
    }
    if ( it != m_structures.end() )
    {
      return m_extendedStructs.find( it->first ) != m_extendedStructs.end();
    }
  }
  return false;
}

std::pair<bool, std::map<size_t, std::vector<size_t>>> VulkanHppGenerator::needsVectorSizeCheck( std::vector<ParamData> const &            params,
                                                                                                 std::map<size_t, VectorParamData> const & vectorParams,
                                                                                                 std::vector<size_t> const &               returnParams,
                                                                                                 std::set<size_t> const & singularParams ) const
{
  std::map<size_t, std::vector<size_t>> countToVectorMap;
  for ( auto const & vpi : vectorParams )
  {
    if ( ( vpi.second.lenParam != INVALID_INDEX ) && ( std::find( returnParams.begin(), returnParams.end(), vpi.first ) == returnParams.end() ) &&
         ( ( singularParams.find( vpi.second.lenParam ) == singularParams.end() ) ||
           isLenByStructMember( params[vpi.first].len, params[vpi.second.lenParam] ) ) )
    {
      countToVectorMap[vpi.second.lenParam].push_back( vpi.first );
    }
  }
  return std::make_pair( std::find_if( countToVectorMap.begin(),
                                       countToVectorMap.end(),
                                       [this, &params]( auto const & cvm ) {
                                         return ( 1 < cvm.second.size() ) || isLenByStructMember( params[cvm.second[0]].len, params[cvm.first] );
                                       } ) != countToVectorMap.end(),
                         countToVectorMap );
}

void VulkanHppGenerator::readCommands( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, { { "comment", {} } } );

  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "command", false } } );
  for ( auto child : children )
  {
    assert( child->Value() == std::string( "command" ) );
    readCommandsCommand( child );
  }
}

void VulkanHppGenerator::readCommandsCommand( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  if ( attributes.find( "alias" ) != attributes.end() )
  {
    // for command aliases, create a copy of the aliased command
    checkAttributes( line,
                     attributes,
                     {},
                     {
                       { "alias", {} },
                       { "name", {} },
                     } );
    checkElements( line, getChildElements( element ), {} );

    std::string alias, name;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "alias" )
      {
        alias = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
        checkForError( name.starts_with( "vk" ), line, "name <" + name + "> should begin with <vk>" );
      }
    }

    auto commandIt = m_commands.find( alias );
    checkForError( commandIt != m_commands.end(), line, "missing command <" + alias + ">" );
    CommandData commandData = commandIt->second;
    commandData.alias       = alias;
    commandData.xmlLine     = line;
    addCommand( name, commandData );
  }
  else
  {
    checkAttributes( line,
                     attributes,
                     {},
                     { { "cmdbufferlevel", { "primary", "secondary" } },
                       { "comment", {} },
                       { "errorcodes", {} },
                       { "queues", { "compute", "decode", "encode", "graphics", "sparse_binding", "transfer" } },
                       { "renderpass", { "both", "inside", "outside" } },
                       { "successcodes", {} },
                       { "tasks", { "action", "indirection", "state", "synchronization" } },
                       { "videocoding", { "both", "inside", "outside" } } } );

    std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
    checkElements( line, children, { { "param", false }, { "proto", true } }, { "implicitexternsyncparams" } );

    CommandData commandData( line );
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "errorcodes" )
      {
        commandData.errorCodes = tokenize( attribute.second, "," );
        // errorCodes are checked in checkCorrectness after complete reading
      }
      else if ( attribute.first == "successcodes" )
      {
        commandData.successCodes = tokenize( attribute.second, "," );
        // successCodes are checked in checkCorrectness after complete reading
      }
    }

    std::string name;
    for ( auto child : children )
    {
      std::string value = child->Value();
      if ( value == "param" )
      {
        commandData.params.push_back( readCommandsCommandParam( child, commandData.params ) );
      }
      else if ( value == "proto" )
      {
        std::tie( name, commandData.returnType ) = readCommandsCommandProto( child );
      }
    }
    assert( !name.empty() );
    checkForError( ( commandData.returnType == "VkResult" ) || commandData.errorCodes.empty(),
                   line,
                   "command <" + name + "> does not return a VkResult but specifies errorcodes" );
    checkForError( ( commandData.returnType == "VkResult" ) || commandData.successCodes.empty(),
                   line,
                   "command <" + name + "> does not return a VkResult but specifies successcodes" );
    for ( auto const & param : commandData.params )
    {
      checkForError( param.stride.empty() || isParam( param.stride, commandData.params ),
                     param.xmlLine,
                     "attribute <stride> holds an unknown value <" + param.stride + ">" );
    }

    registerDeleter( name, std::make_pair( name, commandData ) );
    addCommand( name, commandData );
  }
}

VulkanHppGenerator::ParamData VulkanHppGenerator::readCommandsCommandParam( tinyxml2::XMLElement const * element, std::vector<ParamData> const & params )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line,
                   attributes,
                   {},
                   { { "altlen", {} },
                     { "externsync", {} },
                     { "len", {} },
                     { "noautovalidity", { "true" } },
                     { "objecttype", { "objectType" } },
                     { "optional", { "false", "true" } },
                     { "stride", {} },
                     { "validstructs", {} } } );
  checkValidStructs( line, attributes );

  ParamData paramData( line );
  for ( auto attribute : attributes )
  {
    if ( attribute.first == "altlen" )
    {
      assert( paramData.len.empty() );
      paramData.len = attribute.second;
      checkForError( altLens.find( paramData.len ) != altLens.end(), line, "attribute <altlen> holds unknown value <" + paramData.len + ">" );
    }
    else if ( attribute.first == "len" )
    {
      if ( paramData.len.empty() )
      {
        checkForError( ( attribute.second == "null-terminated" ) || isParam( attribute.second, params ) || isLenByStructMember( attribute.second, params ),
                       line,
                       "attribute <len> holds an unknown value <" + attribute.second + ">" );
        paramData.len = attribute.second;
      }
    }
    else if ( attribute.first == "stride" )
    {
      paramData.stride = attribute.second;
    }
    else if ( attribute.first == "optional" )
    {
      paramData.optional = ( attribute.second == "true" );
    }
  }

  NameData nameData;
  std::tie( nameData, paramData.type ) = readNameAndType( element );

  checkForError( m_types.find( paramData.type.type ) != m_types.end(), line, "unknown type <" + paramData.type.type + ">" );
  checkForError( paramData.type.prefix.empty() || ( paramData.type.prefix == "const" ) || ( paramData.type.prefix == "const struct" ) ||
                   ( paramData.type.prefix == "struct" ),
                 line,
                 "unexpected type prefix <" + paramData.type.prefix + ">" );
  checkForError( paramData.type.postfix.empty() || ( paramData.type.postfix == "*" ) || ( paramData.type.postfix == "**" ) ||
                   ( paramData.type.postfix == "* const *" ),
                 line,
                 "unexpected type postfix <" + paramData.type.postfix + ">" );
  checkForError( std::find_if( params.begin(), params.end(), [&name = nameData.name]( ParamData const & pd ) { return pd.name == name; } ) == params.end(),
                 line,
                 "command param <" + nameData.name + "> already used" );
  paramData.name       = nameData.name;
  paramData.arraySizes = nameData.arraySizes;

  return paramData;
}

std::pair<std::string, std::string> VulkanHppGenerator::readCommandsCommandProto( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );

  auto [nameData, typeInfo] = readNameAndType( element );

  checkForError( nameData.name.starts_with( "vk" ), line, "name <" + nameData.name + "> does not begin with <vk>" );
  checkForError( nameData.arraySizes.empty(), line, "name <" + nameData.name + "> with unsupported arraySizes" );
  checkForError( m_types.find( typeInfo.type ) != m_types.end(), line, "unknown type <" + typeInfo.type + ">" );
  checkForError( typeInfo.prefix.empty(), line, "unexpected type prefix <" + typeInfo.prefix + ">" );
  checkForError( typeInfo.postfix.empty(), line, "unexpected type postfix <" + typeInfo.postfix + ">" );
  checkForError( m_commands.find( nameData.name ) == m_commands.end(), line, "command <" + nameData.name + "> already specified" );

  return std::make_pair( nameData.name, typeInfo.type );
}

void VulkanHppGenerator::readEnums( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, { { "bitwidth", { "64" } }, { "comment", {} }, { "type", { "bitmask", "enum" } } } );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );

  std::string bitwidth, name, type;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "bitwidth" )
    {
      bitwidth = attribute.second;
    }
    else if ( attribute.first == "name" )
    {
      name = attribute.second;
    }
    else if ( attribute.first == "type" )
    {
      type = attribute.second;
    }
  }
  assert( !name.empty() );

  if ( name == "API Constants" )
  {
    checkElements( line, children, { { "enum", false } }, {} );
    for ( auto const & child : children )
    {
      readEnumsConstant( child );
    }
  }
  else
  {
    checkElements( line, children, {}, { "comment", "enum", "unused" } );
    checkForError( !type.empty(), line, "enum without type" );

    // get the EnumData entry in enum map
    std::map<std::string, EnumData>::iterator enumIt = m_enums.find( name );
    if ( enumIt == m_enums.end() )
    {
      enumIt =
        std::find_if( m_enums.begin(), m_enums.end(), [&name]( std::pair<std::string, EnumData> const & enumData ) { return enumData.second.alias == name; } );
    }
    checkForError( enumIt != m_enums.end(), line, "enum <" + name + "> is not listed as enum in the types section" );
    checkForError( enumIt->second.values.empty(), line, "enum <" + name + "> already holds values" );

    // mark it as a bitmask, if it is one
    bool bitmask = ( type == "bitmask" );
    if ( bitmask )
    {
      checkForError( name.find( "FlagBits" ) != std::string::npos, line, "bitmask <" + name + "> does not contain <FlagBits>" );
    }
    enumIt->second.isBitmask = bitmask;
    enumIt->second.bitwidth  = bitwidth;

    // read the names of the enum values
    for ( auto child : children )
    {
      std::string value = child->Value();
      if ( value == "comment" )
      {
        readComment( child );
      }
      else if ( value == "enum" )
      {
        readEnumsEnum( child, enumIt );
      }
    }
  }
}

void VulkanHppGenerator::readEnumsConstant( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, { { "alias", {} }, { "comment", {} }, { "type", {} }, { "value", {} } } );
  checkElements( line, getChildElements( element ), {} );

  std::string alias, name, value;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "alias" )
    {
      checkForError( m_constants.find( attribute.second ) != m_constants.end(), line, "unknown enum constant alias <" + attribute.second + ">" );
      alias = attribute.second;
    }
    else if ( attribute.first == "name" )
    {
      checkForError( m_constants.find( attribute.second ) == m_constants.end(), line, "already specified enum constant <" + attribute.second + ">" );
      name = attribute.second;
    }
    else if ( attribute.first == "value" )
    {
      checkForError( !attribute.second.empty(), line, "value of enum constant is empty" );
      value = attribute.second;
    }
  }
  checkForError( alias.empty() != value.empty(), line, "for enum <" + name + "> either alias or value need to be specified" );
  m_constants[name] = alias.empty() ? value : m_constants[alias];
}

void VulkanHppGenerator::readEnumsEnum( tinyxml2::XMLElement const * element, std::map<std::string, EnumData>::iterator enumIt )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  if ( attributes.find( "alias" ) != attributes.end() )
  {
    checkAttributes( line, attributes, { { "alias", {} }, { "name", {} } }, { { "comment", {} } } );
    checkElements( line, getChildElements( element ), {} );

    std::string alias, bitpos, name, value;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "alias" )
      {
        alias = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
    }
    assert( !name.empty() );

    enumIt->second.addEnumAlias( line, name, alias );
  }
  else
  {
    checkAttributes(
      line, attributes, { { "name", {} } }, { { "bitpos", {} }, { "comment", {} }, { "protect", { "VK_ENABLE_BETA_EXTENSIONS" } }, { "value", {} } } );
    checkElements( line, getChildElements( element ), {} );

    std::string alias, bitpos, name, protect, value;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "bitpos" )
      {
        bitpos = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
      else if ( attribute.first == "protect" )
      {
        protect = attribute.second;
      }
      else if ( attribute.first == "value" )
      {
        value = attribute.second;
      }
    }

    std::string prefix = generateEnumSuffixes( enumIt->first, enumIt->second.isBitmask, m_tags ).first;
    checkForError( name.starts_with( prefix ), line, "encountered enum value <" + name + "> that does not begin with expected prefix <" + prefix + ">" );

    checkForError( bitpos.empty() ^ value.empty(), line, "invalid set of attributes for enum <" + name + ">" );
    enumIt->second.addEnumValue( line, name, protect, !bitpos.empty(), "" );
  }
}

std::string VulkanHppGenerator::readComment( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );
  checkElements( line, getChildElements( element ), {} );

  return element->GetText();
}

void VulkanHppGenerator::readExtensions( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), { { "comment", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "extension", false } } );

  for ( auto child : children )
  {
    assert( child->Value() == std::string( "extension" ) );
    readExtensionsExtension( child );
  }
}

void VulkanHppGenerator::readExtensionsExtension( tinyxml2::XMLElement const * element )
{
  int                                       line       = element->GetLineNum();
  std::map<std::string, std::string>        attributes = getAttributes( element );
  std::vector<tinyxml2::XMLElement const *> children   = getChildElements( element );

  auto it = attributes.find( "supported" );
  checkForError( it != attributes.end(), line, "Missing attribute <supported> for extension!" );

  if ( it->second == "disabled" )
  {
    checkElements( line, children, {}, { "require" } );
    // kick out all the disabled stuff we've read before !!
    for ( auto const & child : children )
    {
      assert( child->Value() == std::string( "require" ) );
      readExtensionsExtensionDisabledRequire( child );
    }
  }
  else
  {
    checkAttributes( line,
                     attributes,
                     { { "name", {} }, { "number", {} }, { "supported", { "disabled", "enabled", "vulkan" } } },
                     { { "author", {} },
                       { "comment", {} },
                       { "contact", {} },
                       { "deprecatedby", {} },
                       { "obsoletedby", {} },
                       { "platform", {} },
                       { "promotedto", {} },
                       { "provisional", { "true" } },
                       { "requires", {} },
                       { "requiresCore", {} },
                       { "sortorder", { "1" } },
                       { "specialuse", { "cadsupport", "d3demulation", "debugging", "devtools", "glemulation" } },
                       { "type", { "device", "instance" } } } );
    checkElements( line, children, { { "require", false } } );

    std::string              deprecatedBy, name, number, obsoletedBy, platform, promotedTo, supported;
    std::vector<std::string> requirements;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "deprecatedby" )
      {
        deprecatedBy = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
      else if ( attribute.first == "number" )
      {
        number = attribute.second;
      }
      else if ( attribute.first == "obsoletedby" )
      {
        obsoletedBy = attribute.second;
      }
      else if ( attribute.first == "platform" )
      {
        platform = attribute.second;
        checkForError( m_platforms.find( platform ) != m_platforms.end(), line, "unknown platform <" + platform + ">" );
      }
      else if ( attribute.first == "promotedto" )
      {
        promotedTo = attribute.second;
      }
      else if ( attribute.first == "provisional" )
      {
        if ( platform.empty() )
        {
          // for now, having the attribute provisional="true" implies attribute platform="provisional" to get
          // stuff protected by VK_ENABLE_BETA_EXTENSIONS
          platform = "provisional";
        }
        checkForError( platform == "provisional",
                       line,
                       "while attribute <provisional> is set to \"true\", attribute <platform> is not set to \"provisional\" but to \"" + platform + "\"" );
      }
      else if ( attribute.first == "requires" )
      {
        requirements = tokenize( attribute.second, "," );
      }
      else if ( attribute.first == "requiresCore" )
      {
        std::string const & requiresCore = attribute.second;
        checkForError( std::find_if( m_features.begin(),
                                     m_features.end(),
                                     [&requiresCore]( std::pair<std::string, FeatureData> const & feature )
                                     { return feature.second.number == requiresCore; } ) != m_features.end(),
                       line,
                       "unknown feature number <" + attribute.second + ">" );
      }
      else if ( attribute.first == "supported" )
      {
        supported = attribute.second;
        assert( supported != "disabled" );
      }
    }

    auto pitb = m_extensions.insert( std::make_pair( name, ExtensionData( line, deprecatedBy, number, obsoletedBy, platform, promotedTo ) ) );
    checkForError( pitb.second, line, "already encountered extension <" + name + ">" );
    for ( auto const & r : requirements )
    {
      checkForError( pitb.first->second.requiresAttribute.insert( r ).second, line, "required extension <" + r + "> already listed" );
    }

    // extract the tag from the name, which is supposed to look like VK_<tag>_<other>
    size_t tagStart = name.find( '_' );
    checkForError( tagStart != std::string::npos, line, "name <" + name + "> is missing an underscore '_'" );
    size_t tagEnd = name.find( '_', tagStart + 1 );
    checkForError( tagEnd != std::string::npos, line, "name <" + name + "> is missing an underscore '_'" );
    std::string tag = name.substr( tagStart + 1, tagEnd - tagStart - 1 );
    checkForError( m_tags.find( tag ) != m_tags.end(), line, "name <" + name + "> is using an unknown tag <" + tag + ">" );

    for ( auto child : children )
    {
      assert( child->Value() == std::string( "require" ) );
      readExtensionsExtensionRequire( child, pitb.first );
    }
  }
}

void VulkanHppGenerator::readExtensionsExtensionDisabledRequire( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "enum", false } }, { "command", "comment", "type" } );

  for ( auto child : children )
  {
    std::string value = child->Value();
    if ( value == "command" )
    {
      readExtensionsExtensionDisabledRequireCommand( child );
    }
    else if ( value == "comment" )
    {
      readComment( child );
    }
    else if ( value == "enum" )
    {
      // just skip enums of disabled extensions
    }
    else
    {
      assert( value == "type" );
      readExtensionsExtensionDisabledRequireType( child );
    }
  }
}

void VulkanHppGenerator::readExtensionsExtensionDisabledRequireCommand( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, {} );
  checkElements( line, getChildElements( element ), {} );

  std::string name = attributes.find( "name" )->second;

  // first unlink the command from its class
  auto commandIt = m_commands.find( name );
  if ( commandIt != m_commands.end() )
  {
    auto handleIt = m_handles.find( commandIt->second.handle );
    checkForError( handleIt != m_handles.end(), line, "cannot find handle corresponding to command <" + name + ">" );
    handleIt->second.commands.erase( commandIt->first );

    // then erase the command from the command list
    m_commands.erase( commandIt );
  }
}

void VulkanHppGenerator::readExtensionsExtensionDisabledRequireType( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, {} );
  checkElements( line, getChildElements( element ), {} );

  std::string name = attributes.find( "name" )->second;

  auto typeIt = m_types.find( name );
  if ( typeIt != m_types.end() )
  {
    switch ( typeIt->second.category )
    {
      case TypeCategory::Bitmask:
        {
          auto bitmasksIt = m_bitmasks.find( name );
          checkForError( bitmasksIt != m_bitmasks.end(), line, "trying to remove unknown bitmask <" + name + ">" );
          checkForError(
            bitmasksIt->second.alias.empty(), line, "trying to remove disabled bitmask <" + name + "> which has alias <" + bitmasksIt->second.alias + ">" );
          m_bitmasks.erase( bitmasksIt );
        }
        break;
      case TypeCategory::Enum:
        {
          auto enumIt = m_enums.find( name );
          checkForError( enumIt != m_enums.end(), line, "trying to remove unknown enum <" + name + ">" );
          checkForError( enumIt->second.alias.empty(), line, "trying to remove disabled enum <" + name + "> which has alias <" + enumIt->second.alias + ">" );
          m_enums.erase( enumIt );
        }
        break;
      case TypeCategory::Struct:
        {
          auto structIt = m_structures.find( name );
          checkForError( structIt != m_structures.end(), line, "trying to remove unknown struct <" + name + ">" );
          auto inverseAliasIt = m_structureAliasesInverse.find( name );
          if ( inverseAliasIt != m_structureAliasesInverse.end() )
          {
            checkForError(
              false, line, "trying to remove disabled structure <" + name + "> which has " + std::to_string( inverseAliasIt->second.size() ) + "aliases" );
          }
          m_structures.erase( structIt );
        }
        break;
      default: checkForError( false, line, "trying to remove <" + name + "> of unhandled type <" + toString( typeIt->second.category ) + ">" ); break;
    }
  }
}

void VulkanHppGenerator::readExtensionsExtensionRequire( tinyxml2::XMLElement const * element, std::map<std::string, ExtensionData>::iterator extensionIt )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, {}, { { "extension", {} }, { "feature", {} } } );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, {}, { "command", "comment", "enum", "type" } );

  std::string requireTitle;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "extension" )
    {
      assert( requireTitle.empty() );
      requireTitle = attribute.second;
      checkForError( std::find_if( extensionIt->second.requireData.begin(),
                                   extensionIt->second.requireData.end(),
                                   [&requireTitle]( RequireData const & rd ) {
                                     return std::find( rd.titles.begin(), rd.titles.end(), requireTitle ) != rd.titles.end();
                                   } ) == extensionIt->second.requireData.end(),
                     line,
                     "required extension <" + requireTitle + "> already listed" );
    }
    else
    {
      assert( attribute.first == "feature" );
      checkForError( m_features.find( attribute.second ) != m_features.end(), line, "unknown feature <" + attribute.second + ">" );
      assert( requireTitle.empty() );
      requireTitle = attribute.second;
    }
  }

  RequireData requireData( line, requireTitle );
  bool        requireDataEmpty = true;
  for ( auto child : children )
  {
    std::string value = child->Value();
    if ( value == "command" )
    {
      readExtensionsExtensionRequireCommand( child, extensionIt->first, requireData );
      requireDataEmpty = false;
    }
    else if ( value == "comment" )
    {
      readComment( child );
    }
    else if ( value == "enum" )
    {
      readRequireEnum( child, extensionIt->first );
    }
    else if ( value == "type" )
    {
      readExtensionsExtensionRequireType( child, extensionIt->first, requireData );
      requireDataEmpty = false;
    }
  }
  if ( !requireDataEmpty )
  {
    extensionIt->second.requireData.push_back( requireData );
  }
}

void VulkanHppGenerator::readExtensionsExtensionRequireCommand( tinyxml2::XMLElement const * element,
                                                                std::string const &          extensionName,
                                                                RequireData &                requireData )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, { { "comment", {} } } );
  checkElements( line, getChildElements( element ), {} );

  std::string name;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "name" )
    {
      name = attribute.second;
    }
  }
  assert( !name.empty() );

  // mark this command be part of this extension
  auto commandIt = m_commands.find( name );
  checkForError(
    commandIt != m_commands.end(), line, "command <" + name + "> marked as required in extension <" + extensionName + "> was not listed before as a command!" );
  if ( commandIt->second.referencedIn.empty() )
  {
    commandIt->second.referencedIn = extensionName;
  }
  else
  {
    checkForError( getPlatform( commandIt->second.referencedIn ) == getPlatform( extensionName ),
                   line,
                   "command <" + name + "> is referenced in extensions <" + commandIt->second.referencedIn + "> and <" + extensionName +
                     "> and thus protected by different platforms <" + getPlatform( commandIt->second.referencedIn ) + "> and <" +
                     getPlatform( extensionName ) + ">!" );
  }
  assert( std::find( requireData.commands.begin(), requireData.commands.end(), name ) == requireData.commands.end() );
  requireData.commands.push_back( name );
}

void VulkanHppGenerator::readExtensionsExtensionRequireType( tinyxml2::XMLElement const * element,
                                                             std::string const &          extensionName,
                                                             RequireData &                requireData )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, { { "comment", {} } } );
  checkElements( line, getChildElements( element ), {} );

  std::string name;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "name" )
    {
      name = attribute.second;
    }
  }
  assert( !name.empty() );

  auto typeIt = m_types.find( name );
  checkForError( typeIt != m_types.end(), line, "failed to find required type <" + name + ">" );
  if ( typeIt->second.referencedIn.empty() )
  {
    typeIt->second.referencedIn = extensionName;
    assert( std::find( requireData.types.begin(), requireData.types.end(), name ) == requireData.types.end() );
    requireData.types.push_back( name );
  }
  else
  {
    checkForError( getPlatform( typeIt->second.referencedIn ) == getPlatform( extensionName ),
                   line,
                   "type <" + name + "> is referenced in extensions <" + typeIt->second.referencedIn + "> and <" + extensionName +
                     "> and thus protected by different platforms <" + getPlatform( typeIt->second.referencedIn ) + "> and <" + getPlatform( extensionName ) +
                     ">!" );
  }
}

void VulkanHppGenerator::readFeature( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "api", { "vulkan" } }, { "comment", {} }, { "name", {} }, { "number", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "require", false } } );

  std::string name, number, modifiedNumber;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "name" )
    {
      name = attribute.second;
    }
    else if ( attribute.first == "number" )
    {
      number         = attribute.second;
      modifiedNumber = number;
      std::replace( modifiedNumber.begin(), modifiedNumber.end(), '.', '_' );
    }
  }
  assert( !name.empty() && !number.empty() );
  checkForError( name == "VK_VERSION_" + modifiedNumber, line, "unexpected formatting of name <" + name + ">" );
  checkForError( m_features.find( name ) == m_features.end(), line, "already specified feature <" + name + ">" );

  auto featureIt = m_features.insert( std::make_pair( name, number ) ).first;
  for ( auto child : children )
  {
    assert( child->Value() == std::string( "require" ) );
    readFeatureRequire( child, featureIt );
  }
}

void VulkanHppGenerator::readFeatureRequire( tinyxml2::XMLElement const * element, std::map<std::string, FeatureData>::iterator featureIt )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, { { "comment", {} } } );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, {}, { "command", "comment", "enum", "type" } );

  RequireData requireData( line, "" );
  bool        requireDataEmpty = true;
  for ( auto child : children )
  {
    std::string value = child->Value();
    if ( value == "command" )
    {
      readFeatureRequireCommand( child, featureIt, requireData );
      requireDataEmpty = false;
    }
    else if ( value == "comment" )
    {
      readComment( child );
    }
    else if ( value == "enum" )
    {
      readRequireEnum( child, "" );
    }
    else if ( value == "type" )
    {
      readFeatureRequireType( child, featureIt, requireData );
      requireDataEmpty = false;
    }
  }
  if ( !requireDataEmpty )
  {
    featureIt->second.requireData.push_back( requireData );
  }
}

void VulkanHppGenerator::readFeatureRequireCommand( tinyxml2::XMLElement const *                 element,
                                                    std::map<std::string, FeatureData>::iterator featureIt,
                                                    RequireData &                                requireData )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, {}, { { "name", {} } } );
  std::string name      = attributes.find( "name" )->second;
  auto        commandIt = m_commands.find( name );
  checkForError( commandIt != m_commands.end(), line, "feature requires unknown command <" + name + ">" );
  checkForError( commandIt->second.referencedIn.empty(), line, "command <" + name + "> already listed with feature <" + commandIt->second.referencedIn + ">" );
  commandIt->second.referencedIn = featureIt->first;
  assert( std::find( requireData.commands.begin(), requireData.commands.end(), name ) == requireData.commands.end() );
  requireData.commands.push_back( name );
}

void VulkanHppGenerator::readFeatureRequireType( tinyxml2::XMLElement const *                 element,
                                                 std::map<std::string, FeatureData>::iterator featureIt,
                                                 RequireData &                                requireData )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, {}, { { "comment", {} }, { "name", {} } } );
  checkElements( line, getChildElements( element ), {} );

  std::string name          = attributes.find( "name" )->second;
  auto        requireTypeIt = std::find_if( requireData.types.begin(), requireData.types.end(), [&name]( std::string const & type ) { return type == name; } );
  checkForError( requireTypeIt == requireData.types.end(), line, "type <" + name + "> already listed for this feature!" );

  // some types are in fact includes (like vk_platform) or defines (like VK_API_VERSION)
  if ( ( m_defines.find( name ) == m_defines.end() ) && ( m_includes.find( name ) == m_includes.end() ) )
  {
    auto typeIt = m_types.find( name );
    checkForError( typeIt != m_types.end(), line, "feature requires unknown type <" + name + ">" );
    checkForError( typeIt->second.referencedIn.empty() || ( typeIt->second.referencedIn == featureIt->first ),
                   line,
                   "type <" + name + "> already listed on feature <" + typeIt->second.referencedIn + ">" );
    typeIt->second.referencedIn = featureIt->first;

    requireData.types.push_back( name );
  }
}

void VulkanHppGenerator::readFormats( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "format", false } } );

  for ( auto child : children )
  {
    readFormatsFormat( child );
  }
}

void VulkanHppGenerator::readFormatsFormat( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line,
                   attributes,
                   { { "blockSize", { "1", "2", "3", "4", "5", "6", "8", "12", "16", "24", "32" } },
                     { "class", {} },
                     { "name", {} },
                     { "texelsPerBlock", { "1", "16", "20", "25", "30", "36", "40", "48", "50", "60", "64", "80", "100", "120", "144" } } },
                   { { "blockExtent", { "1", "2", "4", "5", "6", "8", "10", "12" } },
                     { "chroma", { "420", "422", "444" } },
                     { "compressed", { "ASTC HDR", "ASTC LDR", "BC", "EAC", "ETC", "ETC2", "PVRTC" } },
                     { "packed", { "8", "16", "32" } } } );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "component", false } }, { "plane", "spirvimageformat" } );

  FormatData  format( line );
  std::string name;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "blockExtent" )
    {
      checkForError( tokenize( attribute.second, "," ).size() == 3, line, "unexpected number of elements in attribute <blockExtent>" );
      format.blockExtent = attribute.second;
    }
    if ( attribute.first == "blockSize" )
    {
      format.blockSize = attribute.second;
    }
    else if ( attribute.first == "chroma" )
    {
      format.chroma = attribute.second;
    }
    else if ( attribute.first == "class" )
    {
      format.classAttribute = attribute.second;
    }
    else if ( attribute.first == "compressed" )
    {
      format.compressed = attribute.second;
    }
    else if ( attribute.first == "name" )
    {
      name = attribute.second;
    }
    else if ( attribute.first == "packed" )
    {
      format.packed = attribute.second;
    }
    else if ( attribute.first == "texelsPerBlock" )
    {
      format.texelsPerBlock = attribute.second;
    }
  }

  auto formatIt = m_enums.find( "VkFormat" );
  assert( formatIt != m_enums.end() );

  checkForError( std::find_if( formatIt->second.values.begin(),
                               formatIt->second.values.end(),
                               [&name]( EnumValueData const & evd ) { return evd.name == name; } ) != formatIt->second.values.end() ||
                   ( formatIt->second.aliases.find( name ) != formatIt->second.aliases.end() ),
                 line,
                 "encountered unknown format <" + name + ">" );
  auto [it, inserted] = m_formats.insert( std::make_pair( name, format ) );
  checkForError( inserted, line, "format <" + name + "> already specified on line " + std::to_string( it->second.xmlLine ) );

  for ( auto child : children )
  {
    std::string value = child->Value();
    if ( value == "component" )
    {
      readFormatsFormatComponent( child, it->second );
    }
    else if ( value == "plane" )
    {
      readFormatsFormatPlane( child, it->second );
    }
    else if ( value == "spirvimageformat" )
    {
      readFormatsFormatSPIRVImageFormat( child, it->second );
    }
  }

  if ( it->second.components.front().bits == "compressed" )
  {
    for ( auto componentIt = std::next( it->second.components.begin() ); componentIt != it->second.components.end(); ++componentIt )
    {
      checkForError( componentIt->bits == "compressed", line, "component is expected to be marked as compressed in attribute <bits>" );
    }
  }
  if ( !it->second.components.front().planeIndex.empty() )
  {
    for ( auto componentIt = std::next( it->second.components.begin() ); componentIt != it->second.components.end(); ++componentIt )
    {
      checkForError( !componentIt->planeIndex.empty(), line, "component is expected to have a planeIndex" );
    }
    size_t planeCount = 1 + std::stoi( it->second.components.back().planeIndex );
    checkForError( it->second.planes.size() == planeCount, line, "number of planes does not fit to largest planeIndex of the components" );
  }
}

void VulkanHppGenerator::readFormatsFormatComponent( tinyxml2::XMLElement const * element, FormatData & formatData )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line,
                   attributes,
                   { { "bits", { "1", "2", "4", "5", "6", "8", "9", "10", "11", "12", "16", "24", "32", "64", "compressed" } },
                     { "name", {} },
                     { "numericFormat", { "SFLOAT", "SINT", "SNORM", "SRGB", "SSCALED", "UFLOAT", "UINT", "UNORM", "USCALED" } } },
                   { { "planeIndex", { "0", "1", "2" } } } );
  checkElements( line, getChildElements( element ), {} );

  formatData.components.emplace_back( line );
  ComponentData & component = formatData.components.back();
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "bits" )
    {
      checkForError(
        ( attribute.second != "compressed" ) || !formatData.compressed.empty(), line, "component of a not compressed format is marked as compressed" );
      component.bits = attribute.second;
    }
    else if ( attribute.first == "name" )
    {
      component.name = attribute.second;
    }
    else if ( attribute.first == "numericFormat" )
    {
      component.numericFormat = attribute.second;
    }
    else if ( attribute.first == "planeIndex" )
    {
      component.planeIndex = attribute.second;
    }
  }
}

void VulkanHppGenerator::readFormatsFormatPlane( tinyxml2::XMLElement const * element, FormatData & formatData )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes(
    line, attributes, { { "compatible", {} }, { "index", { "0", "1", "2" } }, { "heightDivisor", { "1", "2" } }, { "widthDivisor", { "1", "2" } } }, {} );
  checkElements( line, getChildElements( element ), {} );

  formatData.planes.emplace_back( line );
  PlaneData & plane = formatData.planes.back();
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "compatible" )
    {
      plane.compatible = attribute.second;
      auto formatIt    = m_enums.find( "VkFormat" );
      assert( formatIt != m_enums.end() );
      checkForError( std::find_if( formatIt->second.values.begin(),
                                   formatIt->second.values.end(),
                                   [&plane]( EnumValueData const & evd ) { return evd.name == plane.compatible; } ) != formatIt->second.values.end(),
                     line,
                     "encountered unknown format <" + plane.compatible + ">" );
    }
    else if ( attribute.first == "index" )
    {
      size_t index = std::stoi( attribute.second );
      checkForError( index + 1 == formatData.planes.size(), line, "unexpected index <" + attribute.second + ">" );
    }
    else if ( attribute.first == "heightDivisor" )
    {
      plane.heightDivisor = attribute.second;
    }
    else if ( attribute.first == "widthDivisor" )
    {
      plane.widthDivisor = attribute.second;
    }
  }
}

void VulkanHppGenerator::readFormatsFormatSPIRVImageFormat( tinyxml2::XMLElement const * element, FormatData & formatData )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, {} );
  checkElements( line, getChildElements( element ), {} );

  for ( auto const & attribute : attributes )
  {
    assert( attribute.first == "name" );
    checkForError( formatData.spirvImageFormat.empty(), line, "spirvimageformat <" + attribute.second + "> already specified" );
    formatData.spirvImageFormat = attribute.second;
  }
}

std::pair<VulkanHppGenerator::NameData, VulkanHppGenerator::TypeInfo> VulkanHppGenerator::readNameAndType( tinyxml2::XMLElement const * element )
{
  int                                       line     = element->GetLineNum();
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "name", true } }, { { "type" } } );

  NameData nameData;
  TypeInfo typeInfo;
  for ( auto child : children )
  {
    line = child->GetLineNum();
    checkAttributes( line, getAttributes( child ), {}, {} );
    checkElements( line, getChildElements( child ), {} );

    std::string value = child->Value();
    if ( value == "name" )
    {
      nameData.name = child->GetText();
      std::string bitCount;
      std::tie( nameData.arraySizes, bitCount ) = readModifiers( child->NextSibling() );
      checkForError( bitCount.empty(), line, "name <" + nameData.name + "> with unsupported bitCount <" + bitCount + ">" );
    }
    else if ( value == "type" )
    {
      typeInfo = readTypeInfo( child );
    }
  }
  return std::make_pair( nameData, typeInfo );
}

void VulkanHppGenerator::readPlatforms( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), { { "comment", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "platform", false } } );

  for ( auto child : children )
  {
    readPlatformsPlatform( child );
  }
}

void VulkanHppGenerator::readPlatformsPlatform( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "comment", {} }, { "name", {} }, { "protect", {} } }, {} );
  checkElements( line, getChildElements( element ), {} );

  std::string name, protect;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "name" )
    {
      name = attribute.second;
      checkForError( !name.empty(), line, "attribute <name> is empty" );
    }
    else if ( attribute.first == "protect" )
    {
      protect = attribute.second;
      checkForError( !protect.empty(), line, "attribute <protect> is empty" );
    }
  }
  assert( !name.empty() && !protect.empty() );

  checkForError( std::find_if( m_platforms.begin(),
                               m_platforms.end(),
                               [&protect]( std::pair<std::string, PlatformData> const & p ) { return p.second.protect == protect; } ) == m_platforms.end(),
                 line,
                 "platform protect <" + protect + "> already specified" );
  checkForError( m_platforms.insert( std::make_pair( name, PlatformData( protect ) ) ).second, line, "platform name <" + name + "> already specified" );
}

void VulkanHppGenerator::readRegistry( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );

  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line,
                 children,
                 { { "commands", true },
                   { "comment", false },
                   { "enums", false },
                   { "extensions", true },
                   { "feature", false },
                   { "platforms", true },
                   { "spirvcapabilities", true },
                   { "spirvextensions", true },
                   { "tags", true },
                   { "types", true } },
                 { "formats" } );
  for ( auto child : children )
  {
    const std::string value = child->Value();
    if ( value == "commands" )
    {
      readCommands( child );
    }
    else if ( value == "comment" )
    {
      std::string comment = readComment( child );
      if ( comment.find( "\nCopyright" ) == 0 )
      {
        setVulkanLicenseHeader( child->GetLineNum(), comment );
      }
    }
    else if ( value == "enums" )
    {
      readEnums( child );
    }
    else if ( value == "extensions" )
    {
      readExtensions( child );
    }
    else if ( value == "feature" )
    {
      readFeature( child );
    }
    else if ( value == "formats" )
    {
      readFormats( child );
    }
    else if ( value == "platforms" )
    {
      readPlatforms( child );
    }
    else if ( value == "spirvcapabilities" )
    {
      readSPIRVCapabilities( child );
    }
    else if ( value == "spirvextensions" )
    {
      readSPIRVExtensions( child );
    }
    else if ( value == "tags" )
    {
      readTags( child );
    }
    else if ( value == "types" )
    {
      readTypes( child );
    }
  }
}

void VulkanHppGenerator::readRequireEnum( tinyxml2::XMLElement const * element, std::string const & extensionName )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  if ( attributes.find( "alias" ) != attributes.end() )
  {
    checkAttributes( line, attributes, { { "alias", {} }, { "name", {} } }, { { "comment", {} }, { "extends", {} } } );
    checkElements( line, getChildElements( element ), {} );

    std::string alias, bitpos, name, extends, extnumber, offset, value;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "alias" )
      {
        alias = attribute.second;
      }
      else if ( attribute.first == "extends" )
      {
        extends = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
    }

    if ( !extends.empty() )
    {
      auto enumIt = m_enums.find( extends );
      checkForError( enumIt != m_enums.end(), line, "feature extends unknown enum <" + extends + ">" );

      // add this enum name to the list of aliases
      enumIt->second.addEnumAlias( line, name, alias );
    }
  }
  else
  {
    checkAttributes( line,
                     attributes,
                     { { "name", {} } },
                     { { "bitpos", {} },
                       { "comment", {} },
                       { "extends", {} },
                       { "dir", { "-" } },
                       { "extnumber", {} },
                       { "offset", {} },
                       { "protect", { "VK_ENABLE_BETA_EXTENSIONS" } },
                       { "value", {} } } );
    checkElements( line, getChildElements( element ), {} );

    std::string bitpos, name, extends, extnumber, offset, protect, value;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "bitpos" )
      {
        bitpos = attribute.second;
      }
      else if ( attribute.first == "extends" )
      {
        extends = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
      else if ( attribute.first == "offset" )
      {
        offset = attribute.second;
      }
      else if ( attribute.first == "protect" )
      {
        protect = attribute.second;
      }
      else if ( attribute.first == "value" )
      {
        value = attribute.second;
      }
    }

    if ( !extends.empty() )
    {
      auto enumIt = m_enums.find( extends );
      checkForError( enumIt != m_enums.end(), line, "feature extends unknown enum <" + extends + ">" );

      // add this enum name to the list of values
      checkForError( bitpos.empty() + offset.empty() + value.empty() == 2,
                     line,
                     "exactly one out of bitpos = <" + bitpos + ">, offset = <" + offset + ">, and value = <" + value + "> are supposed to be empty" );
      enumIt->second.addEnumValue( element->GetLineNum(), name, protect, !bitpos.empty(), extensionName );
    }
    else if ( value.empty() )
    {
      checkForError( m_constants.find( name ) != m_constants.end(), line, "unknown required enum <" + name + ">" );
    }
  }
}

void VulkanHppGenerator::readSPIRVCapabilities( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "comment", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, {}, { "spirvcapability" } );

  for ( auto child : children )
  {
    assert( child->Value() == std::string( "spirvcapability" ) );
    readSPIRVCapabilitiesSPIRVCapability( child );
  }
}

void VulkanHppGenerator::readSPIRVCapabilitiesSPIRVCapability( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, {}, { "enable" } );

  for ( auto child : children )
  {
    assert( child->Value() == std::string( "enable" ) );
    readSPIRVCapabilitiesSPIRVCapabilityEnable( child );
  }
}

void VulkanHppGenerator::readSPIRVCapabilitiesSPIRVCapabilityEnable( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkElements( line, getChildElements( element ), {}, {} );

  if ( attributes.find( "extension" ) != attributes.end() )
  {
    readSPIRVCapabilitiesSPIRVCapabilityEnableExtension( line, attributes );
  }
  else if ( attributes.find( "property" ) != attributes.end() )
  {
    readSPIRVCapabilitiesSPIRVCapabilityEnableProperty( line, attributes );
  }
  else if ( attributes.find( "struct" ) != attributes.end() )
  {
    readSPIRVCapabilitiesSPIRVCapabilityEnableStruct( line, attributes );
  }
  else if ( attributes.find( "version" ) != attributes.end() )
  {
    readSPIRVCapabilitiesSPIRVCapabilityEnableVersion( line, attributes );
  }
  else
  {
    checkForError( false, line, "unknown set of attributes specified for SPIR-V capability" );
  }
}

void VulkanHppGenerator::readSPIRVCapabilitiesSPIRVCapabilityEnableExtension( int xmlLine, std::map<std::string, std::string> const & attributes )
{
  checkAttributes( xmlLine, attributes, { { "extension", {} } }, {} );

  checkForError( attributes.size() == 1, xmlLine, "unexpected attributes in addition to <extension> specified for SPIR-V capability" );
  for ( auto const & attribute : attributes )
  {
    assert( attribute.first == "extension" );
    checkForError(
      m_extensions.find( attribute.second ) != m_extensions.end(), xmlLine, "unknown extension <" + attribute.second + "> specified for SPIR-V capability" );
  }
}

void VulkanHppGenerator::readSPIRVCapabilitiesSPIRVCapabilityEnableProperty( int xmlLine, std::map<std::string, std::string> const & attributes )
{
  checkAttributes( xmlLine, attributes, { { "member", {} }, { "property", {} }, { "requires", {} }, { "value", {} } }, {} );

  std::string member, property, value;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "member" )
    {
      member = attribute.second;
    }
    else if ( attribute.first == "property" )
    {
      property = attribute.second;
    }
    if ( attribute.first == "requires" )
    {
      std::vector<std::string> requiresAttribute = tokenize( attribute.second, "," );
      for ( auto const & r : requiresAttribute )
      {
        checkForError( ( m_features.find( r ) != m_features.end() ) || ( m_extensions.find( r ) != m_extensions.end() ),
                       xmlLine,
                       "unknown requires <" + r + "> specified for SPIR-V capability" );
      }
    }
    else if ( attribute.first == "value" )
    {
      value = attribute.second;
    }
  }
  assert( !member.empty() && !property.empty() && !value.empty() );

  auto propertyIt = m_structures.find( property );
  checkForError( propertyIt != m_structures.end(), xmlLine, "unknown property <" + property + "> specified for SPIR-V capability" );
  auto memberIt = findStructMemberIt( member, propertyIt->second.members );
  checkForError( memberIt != propertyIt->second.members.end(), xmlLine, "unknown member <" + member + "> specified for SPIR-V capability" );
  if ( memberIt->type.type == "VkBool32" )
  {
    checkForError( ( value == "VK_FALSE" ) || ( value == "VK_TRUE" ),
                   xmlLine,
                   "unknown value <" + value + "> for boolean member <" + member + "> specified for SPIR-V capability" );
  }
  else
  {
    auto bitmaskIt = m_bitmasks.find( memberIt->type.type );
    checkForError( bitmaskIt != m_bitmasks.end(), xmlLine, "attribute member = <" + member + "> specified for SPIR-V capability is not a bitmask" );
    assert( !bitmaskIt->second.requirements.empty() );
    auto enumIt = m_enums.find( bitmaskIt->second.requirements );
    checkForError( enumIt != m_enums.end(),
                   xmlLine,
                   "attribute member = <" + member + "> specified for SPIR-V capability requires an unknown enum <" + bitmaskIt->second.requirements + ">" );
    auto valueIt =
      std::find_if( enumIt->second.values.begin(), enumIt->second.values.end(), [&value]( EnumValueData const & evd ) { return evd.name == value; } );
    checkForError( valueIt != enumIt->second.values.end(), xmlLine, "unknown attribute value = <" + value + "> specified for SPIR-V capability" );
  }
}

void VulkanHppGenerator::readSPIRVCapabilitiesSPIRVCapabilityEnableStruct( int xmlLine, std::map<std::string, std::string> const & attributes )
{
  checkAttributes( xmlLine, attributes, { { "feature", {} }, { "struct", {} } }, { { "alias", {} }, { "requires", {} } } );

  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "requires" )
    {
      std::vector<std::string> requiresAttribute = tokenize( attribute.second, "," );
      for ( auto const & r : requiresAttribute )
      {
        checkForError( ( m_features.find( r ) != m_features.end() ) || ( m_extensions.find( r ) != m_extensions.end() ),
                       xmlLine,
                       "unknown requires <" + r + "> specified for SPIR-V capability" );
      }
    }
    else if ( attribute.first == "struct" )
    {
      checkForError( ( m_structures.find( attribute.second ) != m_structures.end() ) ||
                       ( m_structureAliases.find( attribute.second ) != m_structureAliases.end() ),
                     xmlLine,
                     "unknown structure <" + attribute.second + "> specified for SPIR-V capability" );
      checkForError( attributes.find( "feature" ) != attributes.end(),
                     xmlLine,
                     "missing feature attribute for SPIR-V capability specified with struct <" + attribute.second + ">" );
    }
    else
    {
      assert( ( attribute.first == "alias" ) || ( attribute.first == "feature" ) );
    }
  }
}

void VulkanHppGenerator::readSPIRVCapabilitiesSPIRVCapabilityEnableVersion( int xmlLine, std::map<std::string, std::string> const & attributes )
{
  checkAttributes( xmlLine, attributes, { { "version", {} } }, {} );

  checkForError( attributes.size() == 1, xmlLine, "unexpected attributes in addition to <version> specified for SPIR-V capability" );
  for ( auto const & attribute : attributes )
  {
    assert( attribute.first == "version" );
    std::string feature = attribute.second;
    if ( feature.starts_with( "VK_API_" ) )
    {
      feature.erase( 3, 4 );  // remove "API_" from the version -> VK_VERSION_x_y
    }
    checkForError( feature.starts_with( "VK_VERSION_" ), xmlLine, "unknown version <" + attribute.second + "> specified for SPIR-V capability" );
    checkForError( m_features.find( feature ) != m_features.end(), xmlLine, "unknown version <" + attribute.second + "> specified for SPIR-V capability" );
  }
}

void VulkanHppGenerator::readSPIRVExtensions( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "comment", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, {}, { "spirvextension" } );

  for ( auto child : children )
  {
    assert( child->Value() == std::string( "spirvextension" ) );
    readSPIRVExtensionsExtension( child );
  }
}

void VulkanHppGenerator::readSPIRVExtensionsExtension( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "name", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, {}, { "enable" } );

  for ( auto child : children )
  {
    assert( child->Value() == std::string( "enable" ) );
    readSPIRVExtensionsExtensionEnable( child );
  }
}

void VulkanHppGenerator::readSPIRVExtensionsExtensionEnable( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, {}, { { "extension", {} }, { "version", {} } } );
  checkElements( line, getChildElements( element ), {}, {} );

  checkForError( !attributes.empty(), line, "no version or extension specified for SPIR-V extension" );
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "extension" )
    {
      checkForError(
        m_extensions.find( attribute.second ) != m_extensions.end(), line, "unknown extension <" + attribute.second + "> specified for SPIR-V extension" );
    }
    else
    {
      assert( attribute.first == "version" );
      std::string feature = attribute.second;
      if ( feature.starts_with( "VK_API_" ) )
      {
        feature.erase( 3, 4 );  // remove "API_" from the version -> VK_VERSION_x_y
      }
      checkForError( feature.starts_with( "VK_VERSION_" ), line, "unknown version <" + attribute.second + "> specified for SPIR-V extension" );
      checkForError( m_features.find( feature ) != m_features.end(), line, "unknown version <" + attribute.second + "> specified for SPIR-V extension" );
    }
  }
}

void VulkanHppGenerator::readTags( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), { { "comment", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "tag", false } } );

  for ( auto child : children )
  {
    readTagsTag( child );
  }
}

void VulkanHppGenerator::readTagsTag( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line, attributes, { { "author", {} }, { "contact", {} }, { "name", {} } }, {} );
  checkElements( line, getChildElements( element ), {} );

  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "name" )
    {
      checkForError( m_tags.find( attribute.second ) == m_tags.end(), line, "tag named <" + attribute.second + "> has already been specified" );
      m_tags.insert( attribute.second );
    }
    else
    {
      checkForError( ( attribute.first == "author" ) || ( attribute.first == "contact" ), line, "unknown attribute <" + attribute.first + ">" );
    }
  }
}

void VulkanHppGenerator::readTypes( tinyxml2::XMLElement const * element )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), { { "comment", {} } }, {} );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "comment", false }, { "type", false } } );

  for ( auto child : children )
  {
    std::string value = child->Value();
    if ( value == "comment" )
    {
      readComment( child );
    }
    else
    {
      assert( value == "type" );
      readTypesType( child );
    }
  }
}

void VulkanHppGenerator::readTypesType( tinyxml2::XMLElement const * element )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );

  auto categoryIt = attributes.find( "category" );
  if ( categoryIt != attributes.end() )
  {
    if ( categoryIt->second == "basetype" )
    {
      readTypesTypeBasetype( element, attributes );
    }
    else if ( categoryIt->second == "bitmask" )
    {
      readTypesTypeBitmask( element, attributes );
    }
    else if ( categoryIt->second == "define" )
    {
      readTypesTypeDefine( element, attributes );
    }
    else if ( categoryIt->second == "enum" )
    {
      readTypesTypeEnum( element, attributes );
    }
    else if ( categoryIt->second == "funcpointer" )
    {
      readTypesTypeFuncpointer( element, attributes );
    }
    else if ( categoryIt->second == "handle" )
    {
      readTypesTypeHandle( element, attributes );
    }
    else if ( categoryIt->second == "include" )
    {
      readTypesTypeInclude( element, attributes );
    }
    else if ( categoryIt->second == "struct" )
    {
      readTypesTypeStruct( element, false, attributes );
    }
    else
    {
      checkForError( categoryIt->second == "union", element->GetLineNum(), "unknown type category <" + categoryIt->second + ">" );
      readTypesTypeStruct( element, true, attributes );
    }
  }
  else
  {
    auto requiresIt = attributes.find( "requires" );
    if ( requiresIt != attributes.end() )
    {
      readTypesTypeRequires( element, attributes );
    }
    else
    {
      checkForError( ( attributes.size() == 1 ) && ( attributes.begin()->first == "name" ) && ( attributes.begin()->second == "int" ), line, "unknown type" );
      checkForError( m_types.insert( std::make_pair( attributes.begin()->second, TypeCategory::Unknown ) ).second,
                     line,
                     "type <" + attributes.begin()->second + "> already specified" );
    }
  }
}

void VulkanHppGenerator::readTypesTypeBasetype( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();
  checkAttributes( line, attributes, { { "category", { "basetype" } } }, {} );

  NameData nameData;
  TypeInfo typeInfo;
  std::tie( nameData, typeInfo ) = readNameAndType( element );

  if ( typeInfo.prefix == "typedef" )
  {
    // remove redundant typeInfo.prefix "typedef"
    typeInfo.prefix.clear();
  }

  checkForError( nameData.arraySizes.empty(), line, "name <" + nameData.name + "> with unsupported arraySizes" );
  checkForError( typeInfo.prefix.empty(), line, "unexpected type prefix <" + typeInfo.prefix + ">" );
  checkForError( typeInfo.postfix.empty() || ( typeInfo.postfix == "*" ), line, "unexpected type postfix <" + typeInfo.postfix + ">" );

  if ( !typeInfo.type.empty() )
  {
    checkForError( m_baseTypes.insert( std::make_pair( nameData.name, BaseTypeData( typeInfo, line ) ) ).second,
                   line,
                   "basetype <" + nameData.name + "> already specified" );
  }
  checkForError(
    m_types.insert( std::make_pair( nameData.name, TypeCategory::BaseType ) ).second, line, "basetype <" + nameData.name + "> already specified as a type" );
}

void VulkanHppGenerator::readTypesTypeBitmask( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();

  auto aliasIt = attributes.find( "alias" );
  if ( aliasIt != attributes.end() )
  {
    checkAttributes( line, attributes, { { "alias", {} }, { "category", { "bitmask" } }, { "name", {} } }, {} );
    checkElements( line, getChildElements( element ), {} );

    std::string alias, name;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "alias" )
      {
        alias = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
    }

    auto bitmasksIt = m_bitmasks.find( alias );
    checkForError( bitmasksIt != m_bitmasks.end(), line, "missing alias <" + alias + ">." );
    checkForError(
      bitmasksIt->second.alias.empty(), line, "alias for bitmask <" + bitmasksIt->first + "> already specified as <" + bitmasksIt->second.alias + ">" );
    bitmasksIt->second.alias = name;
    checkForError( m_types.insert( std::make_pair( name, TypeCategory::Bitmask ) ).second, line, "aliased bitmask <" + name + "> already specified as a type" );
  }
  else
  {
    checkAttributes( line, attributes, { { "category", { "bitmask" } } }, { { "bitvalues", {} }, { "requires", {} } } );

    std::string bitvalues, requirements;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "bitvalues" )
      {
        bitvalues = attribute.second;
      }
      else if ( attribute.first == "requires" )
      {
        requirements = attribute.second;
      }
    }

    NameData nameData;
    TypeInfo typeInfo;
    std::tie( nameData, typeInfo ) = readNameAndType( element );

    checkForError( nameData.name.starts_with( "Vk" ), line, "name <" + nameData.name + "> does not begin with <Vk>" );
    checkForError( nameData.arraySizes.empty(), line, "name <" + nameData.name + "> with unsupported arraySizes" );
    checkForWarning( ( typeInfo.type == "VkFlags" ) || ( typeInfo.type == "VkFlags64" ), line, "unexpected bitmask type <" + typeInfo.type + ">" );
    checkForError( typeInfo.prefix == "typedef", line, "unexpected type prefix <" + typeInfo.prefix + ">" );
    checkForError( typeInfo.postfix.empty(), line, "unexpected type postfix <" + typeInfo.postfix + ">" );
    checkForError( bitvalues.empty() || requirements.empty(), line, "attributes <bitvalues> and <requires> are both specified" );
    checkForError( ( typeInfo.type != "VkFlags64" ) || !bitvalues.empty(), line, "bitmask of type <VkFlags64> needs attribute bitvalues to be set" );

    if ( !bitvalues.empty() )
    {
      requirements = bitvalues;
    }
    m_bitmasks.insert( std::make_pair( nameData.name, BitmaskData( requirements, typeInfo.type, line ) ) );
    checkForError(
      m_types.insert( std::make_pair( nameData.name, TypeCategory::Bitmask ) ).second, line, "bitmask <" + nameData.name + "> already specified as a type" );
  }
}

void VulkanHppGenerator::readTypesTypeDefine( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();
  checkAttributes( line, attributes, { { "category", { "define" } } }, { { "name", {} }, { "requires", {} } } );

  std::string name;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "name" )
    {
      name = attribute.second;
    }
    else if ( attribute.first == "requires" )
    {
      checkForError( m_defines.find( attribute.second ) != m_defines.end(), line, "using undefined requires <" + attribute.second + ">" );
    }
  }

  if ( !name.empty() )
  {
    checkForError( !element->FirstChildElement(), line, "unknown formatting of type category=define name <" + name + ">" );
    checkForError( element->LastChild() && element->LastChild()->ToText() && element->LastChild()->ToText()->Value(),
                   line,
                   "unknown formatting of type category=define named <" + name + ">" );

    // filter out the check for the different types of VK_DEFINE_NON_DISPATCHABLE_HANDLE
    if ( name == "VK_USE_64_BIT_PTR_DEFINES" )
    {
      m_typesafeCheck = "#if ( VK_USE_64_BIT_PTR_DEFINES == 1 )";
    }
    else if ( ( name == "VK_DEFINE_NON_DISPATCHABLE_HANDLE" ) && ( m_typesafeCheck.empty() ) )
    {
      std::string text  = element->LastChild()->ToText()->Value();
      size_t      start = text.find( "#if defined(__LP64__)" );
      checkForError( start != std::string::npos, line, "unexpected text in type category=define named <" + name + ">" );
      size_t end = text.find_first_of( "\r\n", start + 1 );
      checkForError( end != std::string::npos, line, "unexpected text in type category=define named <" + name + ">" );
      m_typesafeCheck = text.substr( start, end - start );
    }
  }
  else if ( element->GetText() )
  {
    std::string text = element->GetText();
    if ( ( text.find( "class" ) != std::string::npos ) || ( text.find( "struct" ) != std::string::npos ) )
    {
      // here are a couple of structs as defines, which really are types!
      tinyxml2::XMLElement const * child = element->FirstChildElement();
      checkForError( child && ( strcmp( child->Value(), "name" ) == 0 ) && child->GetText(), line, "unexpected formatting of type category=define" );
      name = child->GetText();
      checkForError( m_types.insert( std::make_pair( name, TypeCategory::Define ) ).second, line, "type <" + name + "> has already been speficied" );
    }
    else
    {
      tinyxml2::XMLElement const * child = element->FirstChildElement();
      checkForError( child && !child->FirstAttribute() && ( strcmp( child->Value(), "name" ) == 0 ) && child->GetText(),
                     line,
                     "unknown formatting of type category define" );
      name = trim( child->GetText() );
      if ( name == "VK_HEADER_VERSION" )
      {
        m_version = trimEnd( element->LastChild()->ToText()->Value() );
      }
      // ignore all the other defines
      checkForWarning( !child->NextSiblingElement() ||
                         ( child->NextSiblingElement() && !child->NextSiblingElement()->FirstAttribute() &&
                           ( strcmp( child->NextSiblingElement()->Value(), "type" ) == 0 ) && !child->NextSiblingElement()->NextSiblingElement() ),
                       line,
                       "unknown formatting of type category define" );
    }
  }

  assert( !name.empty() );
  checkForError( m_defines.insert( name ).second, line, "define <" + name + "> has already been specified" );
}

void VulkanHppGenerator::readTypesTypeEnum( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();
  checkAttributes( line, attributes, { { "category", { "enum" } }, { "name", {} } }, { { "alias", {} } } );
  checkElements( line, getChildElements( element ), {} );

  std::string alias, name;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "alias" )
    {
      alias = attribute.second;
      checkForError( !alias.empty(), line, "enum with empty alias" );
    }
    else if ( attribute.first == "name" )
    {
      name = attribute.second;
      checkForError( !name.empty(), line, "enum with empty name" );
      checkForError( m_enums.find( name ) == m_enums.end(), line, "enum <" + name + "> already specified" );
    }
  }
  assert( !name.empty() );

  if ( alias.empty() )
  {
    checkForError( m_enums.insert( std::make_pair( name, EnumData( line ) ) ).second, line, "enum <" + name + "> already specified" );
  }
  else
  {
    auto enumIt = m_enums.find( alias );
    checkForError( enumIt != m_enums.end(), line, "enum with unknown alias <" + alias + ">" );
    checkForError( enumIt->second.alias.empty(), line, "enum <" + enumIt->first + "> already has an alias <" + enumIt->second.alias + ">" );
    enumIt->second.alias = name;
  }
  checkForError( m_types.insert( std::make_pair( name, TypeCategory::Enum ) ).second, line, "enum <" + name + "> already specified as a type" );
}

void VulkanHppGenerator::readTypesTypeFuncpointer( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();
  checkAttributes( line, attributes, { { "category", { "funcpointer" } } }, { { "requires", {} } } );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "name", true } }, { "type" } );

  std::string requirements;
  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "requires" )
    {
      requirements = attribute.second;
    }
  }

  auto                  funcPointerIt = m_funcPointers.end();
  std::set<std::string> argumentNames;
  for ( auto const & child : children )
  {
    std::string value     = child->Value();
    int         childLine = child->GetLineNum();
    if ( value == "name" )
    {
      std::string name = child->GetText();
      checkForError( !name.empty(), childLine, "funcpointer with empty name" );
      checkForError( m_funcPointers.find( name ) == m_funcPointers.end(), childLine, "funcpointer <" + name + "> already specified" );
      funcPointerIt = m_funcPointers.insert( std::make_pair( name, FuncPointerData( requirements, line ) ) ).first;
      checkForError(
        m_types.insert( std::make_pair( name, TypeCategory::FuncPointer ) ).second, childLine, "funcpointer <" + name + "> already specified as a type" );
    }
    else if ( value == "type" )
    {
      assert( funcPointerIt != m_funcPointers.end() );
      std::string type = child->GetText();
      funcPointerIt->second.arguments.push_back( { type, childLine } );

      auto         sibling      = child->NextSibling();
      char const * siblingValue = sibling->Value();
      assert( siblingValue != nullptr );
      std::string argumentName = siblingValue;
      argumentName             = argumentName.substr( argumentName.find_first_not_of( "* " ) );
      argumentName             = argumentName.substr( 0, argumentName.find_first_of( ",)" ) );
      checkForError( argumentNames.insert( argumentName ).second,
                     childLine,
                     "funcpointer <" + funcPointerIt->first + "> already has an argument named <" + argumentName + ">" );
    }
  }
}

void VulkanHppGenerator::readTypesTypeHandle( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();

  auto aliasIt = attributes.find( "alias" );
  if ( aliasIt != attributes.end() )
  {
    checkAttributes( line, attributes, { { "alias", {} }, { "category", { "handle" } }, { "name", {} } }, {} );
    checkElements( line, getChildElements( element ), {} );

    auto handlesIt = m_handles.find( aliasIt->second );
    checkForError( handlesIt != m_handles.end(), line, "using unspecified alias <" + aliasIt->second + ">." );
    checkForError( handlesIt->second.alias.empty(), line, "handle <" + handlesIt->first + "> already has an alias <" + handlesIt->second.alias + ">" );
    handlesIt->second.alias = attributes.find( "name" )->second;
    checkForError( m_types.insert( std::make_pair( handlesIt->second.alias, TypeCategory::Handle ) ).second,
                   line,
                   "handle alias <" + handlesIt->second.alias + "> already specified as a type" );
  }
  else
  {
    checkAttributes( line, attributes, { { "category", { "handle" } } }, { { "objtypeenum", {} }, { "parent", {} } } );

    std::string objTypeEnum, parent;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "objtypeenum" )
      {
        objTypeEnum = attribute.second;
      }
      else if ( attribute.first == "parent" )
      {
        parent = attribute.second;
      }
    }

    NameData nameData;
    TypeInfo typeInfo;
    std::tie( nameData, typeInfo ) = readNameAndType( element );
    const bool isDispatchable      = typeInfo.type == "VK_DEFINE_HANDLE";

    checkForError( nameData.name.starts_with( "Vk" ), line, "name <" + nameData.name + "> does not begin with <Vk>" );
    checkForError( nameData.arraySizes.empty(), line, "name <" + nameData.name + "> with unsupported arraySizes" );
    checkForError( ( typeInfo.type == "VK_DEFINE_HANDLE" ) || ( typeInfo.type == "VK_DEFINE_NON_DISPATCHABLE_HANDLE" ),
                   line,
                   "handle with invalid type <" + typeInfo.type + ">" );
    checkForError( typeInfo.prefix.empty(), line, "unexpected type prefix <" + typeInfo.prefix + ">" );
    checkForError( typeInfo.postfix == "(", line, "unexpected type postfix <" + typeInfo.postfix + ">" );
    checkForError( !objTypeEnum.empty(), line, "handle <" + nameData.name + "> does not specify attribute \"objtypeenum\"" );

    checkForError( parent.find( ',' ) == std::string::npos, line, "mulitple parents specified for handle <" + nameData.name + ">" );
    checkForError( m_handles.insert( std::make_pair( nameData.name, HandleData( parent, objTypeEnum, isDispatchable, line ) ) ).second,
                   line,
                   "handle <" + nameData.name + "> already specified" );
    checkForError(
      m_types.insert( std::make_pair( nameData.name, TypeCategory::Handle ) ).second, line, "handle <" + nameData.name + "> already specified as a type" );
  }
}

void VulkanHppGenerator::readTypesTypeInclude( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();
  checkAttributes( line, attributes, { { "category", { "include" } }, { "name", {} } }, {} );
  checkElements( line, getChildElements( element ), {} );

  std::string name = attributes.find( "name" )->second;
  checkForError( m_includes.insert( name ).second, element->GetLineNum(), "include named <" + name + "> already specified" );
}

void VulkanHppGenerator::readTypesTypeRequires( tinyxml2::XMLElement const * element, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();
  checkAttributes( line, attributes, { { "name", {} }, { "requires", {} } }, {} );
  checkElements( line, getChildElements( element ), {} );

  for ( auto attribute : attributes )
  {
    if ( attribute.first == "name" )
    {
      checkForError(
        m_types.insert( std::make_pair( attribute.second, TypeCategory::Requires ) ).second, line, "type named <" + attribute.second + "> already specified" );
    }
    else
    {
      assert( attribute.first == "requires" );
      checkForError( m_includes.find( attribute.second ) != m_includes.end(), line, "type requires unknown include <" + attribute.second + ">" );
    }
  }
}

void VulkanHppGenerator::readTypesTypeStruct( tinyxml2::XMLElement const * element, bool isUnion, std::map<std::string, std::string> const & attributes )
{
  int line = element->GetLineNum();
  if ( attributes.find( "alias" ) != attributes.end() )
  {
    checkAttributes( line, attributes, { { "alias", {} }, { "category", { "struct" } }, { "name", {} } }, {} );
    checkElements( line, getChildElements( element ), {}, {} );

    std::string alias, name;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "alias" )
      {
        alias = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
    }

    checkForError(
      m_structureAliases.insert( std::make_pair( name, StructureAliasData( alias, line ) ) ).second, line, "structure alias <" + name + "> already used" );
    checkForError( m_structureAliasesInverse[alias].insert( name ).second, line, "structure alias <" + name + "> already used with structure <" + alias + ">" );
    checkForError( m_types.insert( std::make_pair( name, TypeCategory::Struct ) ).second, line, "struct <" + name + "> already specified as a type" );
  }
  else
  {
    checkAttributes( line,
                     attributes,
                     { { "category", { isUnion ? "union" : "struct" } }, { "name", {} } },
                     { { "allowduplicate", { "false", "true" } }, { "comment", {} }, { "returnedonly", { "true" } }, { "structextends", {} } } );
    std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
    checkElements( line, children, {}, { "member", "comment" } );

    std::string              category, name;
    std::vector<std::string> structExtends;
    bool                     allowDuplicate = false;
    bool                     returnedOnly   = false;
    for ( auto const & attribute : attributes )
    {
      if ( attribute.first == "allowduplicate" )
      {
        allowDuplicate = ( attribute.second == "true" );
      }
      else if ( attribute.first == "category" )
      {
        category = attribute.second;
      }
      else if ( attribute.first == "name" )
      {
        name = attribute.second;
      }
      else if ( attribute.first == "returnedonly" )
      {
        checkForError( attribute.second == "true", line, "unknown value for attribute returnedonly: <" + attribute.second + ">" );
        returnedOnly = true;
      }
      else if ( attribute.first == "structextends" )
      {
        structExtends = tokenize( attribute.second, "," );
      }
    }
    assert( !name.empty() );
    // make this warn a check, as soon as vk.xml has been fixed on attribute "allowduplicate" !
    checkForWarning( !allowDuplicate || !structExtends.empty(), line, "attribute <allowduplicate> is true, but no structures are listed in <structextends>" );

    checkForError( m_structures.find( name ) == m_structures.end(), line, "struct <" + name + "> already specfied" );
    std::map<std::string, StructureData>::iterator it = m_structures.insert( std::make_pair( name, StructureData( structExtends, line ) ) ).first;
    it->second.allowDuplicate                         = allowDuplicate;
    it->second.isUnion                                = isUnion;
    it->second.returnedOnly                           = returnedOnly;

    for ( auto child : children )
    {
      std::string value = child->Value();
      if ( value == "comment" )
      {
        readComment( child );
      }
      else if ( value == "member" )
      {
        readTypesTypeStructMember( child, it->second.members, isUnion );
      }
    }
    it->second.subStruct = determineSubStruct( *it );

    // check if multiple structure members use the very same (not empty) len attribute
    // Note: even though the arrays are not marked as optional, they still might be mutually exclusive (like in
    // VkWriteDescriptorSet)! That is, there's not enough information available in vk.xml to decide on that, so we
    // need this external knowledge!
    static std::set<std::string> mutualExclusiveStructs = { "VkAccelerationStructureBuildGeometryInfoKHR", "VkWriteDescriptorSet" };
    static std::set<std::string> multipleLenStructs     = { "VkImageConstraintsInfoFUCHSIA",
                                                        "VkIndirectCommandsLayoutTokenNV",
                                                        "VkPresentInfoKHR",
                                                        "VkSemaphoreWaitInfo",
                                                        "VkSubmitInfo",
                                                        "VkSubpassDescription",
                                                        "VkSubpassDescription2",
                                                        "VkWin32KeyedMutexAcquireReleaseInfoKHR",
                                                        "VkWin32KeyedMutexAcquireReleaseInfoNV" };
    bool                         warned                 = false;
    for ( auto m0It = it->second.members.begin(); !warned && ( m0It != it->second.members.end() ); ++m0It )
    {
      if ( !m0It->len.empty() && ( m0It->len.front() != "null-terminated" ) )
      {
        for ( auto m1It = std::next( m0It ); !warned && ( m1It != it->second.members.end() ); ++m1It )
        {
          if ( !m1It->len.empty() && ( m0It->len.front() == m1It->len.front() ) )
          {
            if ( mutualExclusiveStructs.find( it->first ) != mutualExclusiveStructs.end() )
            {
              it->second.mutualExclusiveLens = true;
            }
            else
            {
              checkForWarning(
                multipleLenStructs.find( it->first ) != multipleLenStructs.end(),
                line,
                "Encountered structure <" + it->first +
                  "> with multiple members referencing the same member for len. Need to be checked if they are supposed to be mutually exclusive." );
              warned = true;
            }
          }
        }
      }
    }

    m_extendedStructs.insert( structExtends.begin(), structExtends.end() );
    checkForError( m_types.insert( std::make_pair( name, ( category == "struct" ) ? TypeCategory::Struct : TypeCategory::Union ) ).second,
                   line,
                   "struct <" + name + "> already specified as a type" );  // log type and alias in m_types
  }
}

void VulkanHppGenerator::readTypesTypeStructMember( tinyxml2::XMLElement const * element, std::vector<MemberData> & members, bool isUnion )
{
  int                                line       = element->GetLineNum();
  std::map<std::string, std::string> attributes = getAttributes( element );
  checkAttributes( line,
                   attributes,
                   {},
                   { { "altlen", {} },
                     { "externsync", { "true" } },
                     { "len", {} },
                     { "limittype", { "bitmask", "bits", "exact", "max", "min", "mul", "noauto", "pot", "range", "struct" } },
                     { "noautovalidity", { "true" } },
                     { "objecttype", { "objectType" } },
                     { "optional", { "false", "true" } },
                     { "selection", {} },
                     { "selector", {} },
                     { "values", {} } } );
  std::vector<tinyxml2::XMLElement const *> children = getChildElements( element );
  checkElements( line, children, { { "name", true }, { "type", true } }, { "comment", "enum" } );

  MemberData memberData( line );

  for ( auto child : children )
  {
    std::string value = child->Value();
    if ( value == "enum" )
    {
      readTypesTypeStructMemberEnum( child, memberData );
    }
    else if ( value == "name" )
    {
      readTypesTypeStructMemberName( child, memberData, members );
    }
    else if ( value == "type" )
    {
      readTypesTypeStructMemberType( child, memberData );
    }
  }

  for ( auto const & attribute : attributes )
  {
    if ( attribute.first == "altlen" )
    {
      assert( memberData.len.empty() );
      memberData.len = tokenize( attribute.second, "," );
      checkForError( memberData.len.size() == 1, line, "member attribute <altlen> holds unknown number of data: " + std::to_string( memberData.len.size() ) );
      checkForError( altLens.find( memberData.len[0] ) != altLens.end(), line, "member attribute <altlen> holds unknown value <" + memberData.len[0] + ">" );
    }
    else if ( attribute.first == "len" )
    {
      if ( memberData.len.empty() )
      {
        memberData.len = tokenize( attribute.second, "," );
        checkForError( !memberData.len.empty() && ( memberData.len.size() <= 2 ),
                       line,
                       "member attribute <len> holds unknown number of data: " + std::to_string( memberData.len.size() ) );
        auto lenMember = findStructMemberIt( memberData.len[0], members );
        checkForError( lenMember != members.end() || ( memberData.len[0] == "null-terminated" ),
                       line,
                       "member attribute <len> holds unknown value <" + memberData.len[0] + ">" );
        if ( lenMember != members.end() )
        {
          checkForError( lenMember->type.prefix.empty() && lenMember->type.postfix.empty(),
                         line,
                         "member attribute <len> references a member of unexpected type <" + lenMember->type.compose( "VULKAN_HPP_NAMESPACE" ) + ">" );
        }
        if ( 1 < memberData.len.size() )
        {
          checkForError( ( memberData.len[1] == "1" ) || ( memberData.len[1] == "null-terminated" ),
                         line,
                         "member attribute <len> holds unknown second value <" + memberData.len[1] + ">" );
        }
      }
    }
    else if ( attribute.first == "noautovalidity" )
    {
      memberData.noAutoValidity = ( attribute.second == "true" );
    }
    else if ( attribute.first == "optional" )
    {
      std::vector<std::string> optional = tokenize( attribute.second, "," );
      memberData.optional.reserve( optional.size() );
      for ( auto const & o : optional )
      {
        memberData.optional.push_back( o == "true" );
      }
    }
    else if ( attribute.first == "selection" )
    {
      checkForError( isUnion, line, "attribute <selection> is used with a non-union structure." );
      memberData.selection = attribute.second;
    }
    else if ( attribute.first == "selector" )
    {
      memberData.selector = attribute.second;
      auto selectorIt     = findStructMemberIt( memberData.selector, members );
      checkForError( selectorIt != members.end(), line, "member attribute <selector> holds unknown value <" + memberData.selector + ">" );
      checkForError( m_enums.find( selectorIt->type.type ) != m_enums.end(),
                     line,
                     "member attribute <selector> references unknown enum type <" + selectorIt->type.type + ">" );
    }
    else if ( attribute.first == "values" )
    {
      std::vector<std::string> values = tokenize( attribute.second, "," );
      checkForError( values.size() == 1, line, "attribute \"values\" holds multiple values <" + attribute.first + ">, but it's expected to hold just one" );
      memberData.value = values[0];
    }
  }

  members.push_back( memberData );
}

void VulkanHppGenerator::readTypesTypeStructMemberEnum( tinyxml2::XMLElement const * element, MemberData & memberData )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );
  checkElements( line, getChildElements( element ), {}, {} );

  std::string enumString = element->GetText();

  checkForError( element->PreviousSibling() && ( strcmp( element->PreviousSibling()->Value(), "[" ) == 0 ) && element->NextSibling() &&
                   ( strcmp( element->NextSibling()->Value(), "]" ) == 0 ),
                 line,
                 std::string( "structure member array specifiation is ill-formatted: <" ) + enumString + ">" );

  memberData.arraySizes.push_back( enumString );
  checkForError( memberData.usedConstant.empty(), line, "struct already holds a constant <" + memberData.usedConstant + ">" );
  memberData.usedConstant = enumString;
}

void VulkanHppGenerator::readTypesTypeStructMemberName( tinyxml2::XMLElement const * element, MemberData & memberData, std::vector<MemberData> const & members )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );
  checkElements( line, getChildElements( element ), {}, {} );

  std::string name = element->GetText();
  checkForError( !isStructMember( name, members ), line, "structure member name <" + name + "> already used" );

  memberData.name                                        = name;
  std::tie( memberData.arraySizes, memberData.bitCount ) = readModifiers( element->NextSibling() );
}

void VulkanHppGenerator::readTypesTypeStructMemberType( tinyxml2::XMLElement const * element, MemberData & memberData )
{
  int line = element->GetLineNum();
  checkAttributes( line, getAttributes( element ), {}, {} );
  checkElements( line, getChildElements( element ), {}, {} );

  memberData.type = readTypeInfo( element );
}

VulkanHppGenerator::TypeInfo VulkanHppGenerator::readTypeInfo( tinyxml2::XMLElement const * element ) const
{
  TypeInfo                  typeInfo;
  tinyxml2::XMLNode const * previousSibling = element->PreviousSibling();
  if ( previousSibling && previousSibling->ToText() )
  {
    typeInfo.prefix = trim( previousSibling->Value() );
  }
  typeInfo.type                         = element->GetText();
  tinyxml2::XMLNode const * nextSibling = element->NextSibling();
  if ( nextSibling && nextSibling->ToText() )
  {
    typeInfo.postfix = trimStars( trimEnd( nextSibling->Value() ) );
  }
  return typeInfo;
}

void VulkanHppGenerator::registerDeleter( std::string const & name, std::pair<std::string, CommandData> const & commandData )
{
  if ( ( commandData.first.substr( 2, 7 ) == "Destroy" ) || ( commandData.first.substr( 2, 4 ) == "Free" ) )
  {
    std::string key;
    size_t      valueIndex;
    switch ( commandData.second.params.size() )
    {
      case 2:
      case 3:
        assert( commandData.second.params.back().type.type == "VkAllocationCallbacks" );
        key        = ( commandData.second.params.size() == 2 ) ? "" : commandData.second.params[0].type.type;
        valueIndex = commandData.second.params.size() - 2;
        break;
      case 4:
        key        = commandData.second.params[0].type.type;
        valueIndex = 3;
        assert( m_handles.find( commandData.second.params[valueIndex].type.type ) != m_handles.end() );
        m_handles.find( commandData.second.params[valueIndex].type.type )->second.deletePool = commandData.second.params[1].type.type;
        break;
      default: assert( false ); valueIndex = 0;
    }
    auto keyHandleIt = m_handles.find( key );
    assert( ( keyHandleIt != m_handles.end() ) &&
            ( keyHandleIt->second.childrenHandles.find( commandData.second.params[valueIndex].type.type ) == keyHandleIt->second.childrenHandles.end() ) );
    keyHandleIt->second.childrenHandles.insert( commandData.second.params[valueIndex].type.type );

    auto handleIt = m_handles.find( commandData.second.params[valueIndex].type.type );
    assert( handleIt != m_handles.end() );
    handleIt->second.deleteCommand = name;
  }
}

void VulkanHppGenerator::rescheduleRAIIHandle( std::string &                              str,
                                               std::pair<std::string, HandleData> const & handle,
                                               std::set<std::string> &                    listedHandles,
                                               std::set<std::string> const &              specialFunctions ) const
{
  listedHandles.insert( handle.first );
  if ( !handle.second.parent.empty() && ( listedHandles.find( handle.second.parent ) == listedHandles.end() ) )
  {
    auto parentIt = m_handles.find( handle.second.parent );
    assert( parentIt != m_handles.end() );
    str += generateRAIIHandle( *parentIt, listedHandles, specialFunctions );
  }

  for ( auto constructorIt : handle.second.constructorIts )
  {
    for ( auto const & param : constructorIt->second.params )
    {
      auto handleIt = m_handles.find( param.type.type );
      if ( handleIt != m_handles.end() && ( listedHandles.find( param.type.type ) == listedHandles.end() ) )
      {
        str += generateRAIIHandle( *handleIt, listedHandles, specialFunctions );
      }
    }
  }
}

std::vector<std::string> VulkanHppGenerator::selectCommandsByHandle( std::vector<RequireData> const & requireData,
                                                                     std::set<std::string> const &    handleCommands,
                                                                     std::set<std::string> &          listedCommands ) const
{
  std::vector<std::string> selectedCommands;
  for ( auto const & require : requireData )
  {
    for ( auto const & command : require.commands )
    {
      if ( ( handleCommands.find( command ) != handleCommands.end() ) && listedCommands.insert( command ).second )
      {
        selectedCommands.push_back( command );
      }
    }
  }
  return selectedCommands;
}

void VulkanHppGenerator::setVulkanLicenseHeader( int line, std::string const & comment )
{
  checkForError( m_vulkanLicenseHeader.empty(), line, "second encounter of a Copyright comment" );
  m_vulkanLicenseHeader = comment;

  // replace any '\n' with "\n// "
  for ( size_t pos = m_vulkanLicenseHeader.find( '\n' ); pos != std::string::npos; pos = m_vulkanLicenseHeader.find( '\n', pos + 1 ) )
  {
    m_vulkanLicenseHeader.replace( pos, 1, "\n// " );
  }
  // replace any " \n" with "\n"
  for ( size_t pos = m_vulkanLicenseHeader.find( " \n" ); pos != std::string::npos; pos = m_vulkanLicenseHeader.find( " \n", pos ) )
  {
    m_vulkanLicenseHeader.replace( pos, 2, "\n" );
  }
  // remove any trailing spaces
  m_vulkanLicenseHeader = trimEnd( m_vulkanLicenseHeader );

  // and add a little message on our own
  m_vulkanLicenseHeader += "\n\n// This header is generated from the Khronos Vulkan XML API Registry.";
  m_vulkanLicenseHeader = trim( m_vulkanLicenseHeader ) + "\n";
}

bool VulkanHppGenerator::skipLeadingGrandParent( std::pair<std::string, HandleData> const & handle ) const
{
  bool skip = false;
  assert( !handle.second.constructorIts.empty() );
  auto constructorIt = handle.second.constructorIts.begin();
  if ( ( 1 < ( *constructorIt )->second.params.size() ) && isHandleType( ( *constructorIt )->second.params[0].type.type ) &&
       ( ( *constructorIt )->second.params[1].type.type == handle.second.parent ) )
  {
    auto parentIt = m_handles.find( handle.second.parent );
    assert( parentIt != m_handles.end() );
    skip = ( ( *constructorIt )->second.params[0].type.type == parentIt->second.parent );
#if !defined( NDEBUG )
    for ( auto it = std::next( constructorIt ); it != handle.second.constructorIts.end(); ++it )
    {
      assert( ( *it )->second.params[0].type.type == ( *constructorIt )->second.params[0].type.type );
      assert( !skip || ( ( *it )->second.params[1].type.type == ( *constructorIt )->second.params[1].type.type ) );
    }
#endif
  }
  return skip;
}

std::string VulkanHppGenerator::toString( TypeCategory category )
{
  switch ( category )
  {
    case TypeCategory::Bitmask: return "bitmask";
    case TypeCategory::BaseType: return "basetype";
    case TypeCategory::Define: return "define";
    case TypeCategory::Enum: return "enum";
    case TypeCategory::FuncPointer: return "funcpointer";
    case TypeCategory::Handle: return "handle";
    case TypeCategory::Requires: return "requires";
    case TypeCategory::Struct: return "struct";
    case TypeCategory::Union: return "union";
    case TypeCategory::Unknown: return "unkown";
    default: assert( false ); return "";
  }
}

void VulkanHppGenerator::EnumData::addEnumAlias( int line, std::string const & name, std::string const & aliasName )
{
  auto aliasIt = aliases.find( name );
  checkForError(
    ( aliasIt == aliases.end() ) || ( aliasIt->second.name == aliasName ), line, "enum alias <" + name + "> already listed for a different enum value" );
  aliases.insert( std::make_pair( name, EnumAliasData( aliasName, line ) ) );
}

void VulkanHppGenerator::EnumData::addEnumValue(
  int line, std::string const & valueName, std::string const & protect, bool bitpos, std::string const & extension )
{
  auto valueIt = std::find_if( values.begin(), values.end(), [&valueName]( EnumValueData const & evd ) { return evd.name == valueName; } );
  if ( valueIt == values.end() )
  {
    values.emplace_back( line, valueName, protect, extension, bitpos );
  }
}

std::string VulkanHppGenerator::TypeInfo::compose( std::string const & nameSpace ) const
{
  return prefix + ( prefix.empty() ? "" : " " ) +
         ( nameSpace.empty() ? type : ( ( ( type.substr( 0, 2 ) == "Vk" ) ? ( nameSpace + "::" ) : "" ) + stripPrefix( type, "Vk" ) ) ) +
         ( postfix.empty() ? "" : " " ) + postfix;
}

VulkanHppGenerator::RequireData::RequireData( int line, std::string const & titles_ ) : titles( tokenize( titles_, "," ) ), xmlLine( line ) {}

//
// VulkanHppGenerator local functions
//

// check the validity of an attributes map
// line       : the line in the xml file where the attributes are listed
// attributes : the map of name/value pairs of the encountered attributes
// required   : the required attributes, with a set of allowed values per attribute
// optional   : the optional attributes, with a set of allowed values per attribute
void checkAttributes( int                                                  line,
                      std::map<std::string, std::string> const &           attributes,
                      std::map<std::string, std::set<std::string>> const & required,
                      std::map<std::string, std::set<std::string>> const & optional )
{
  // check if all required attributes are included and if there is a set of allowed values, check if the actual
  // value is part of that set
  for ( auto const & r : required )
  {
    auto attributesIt = attributes.find( r.first );
    checkForError( attributesIt != attributes.end(), line, "missing attribute <" + r.first + ">" );
    checkForError( r.second.empty() || ( r.second.find( attributesIt->second ) != r.second.end() ),
                   line,
                   "unexpected attribute value <" + attributesIt->second + "> in attribute <" + r.first + ">" );
  }
  // check if all not required attributes or optional, and if there is a set of allowed values, check if the
  // actual value is part of that set
  for ( auto const & a : attributes )
  {
    if ( required.find( a.first ) == required.end() )
    {
      auto optionalIt = optional.find( a.first );
      if ( optionalIt == optional.end() )
      {
        checkForWarning( false, line, "unknown attribute <" + a.first + ">" );
        continue;
      }
      if ( !optionalIt->second.empty() )
      {
        std::vector<std::string> values = tokenize( a.second, "," );
        for ( auto const & v : values )
        {
          checkForWarning(
            optionalIt->second.find( v ) != optionalIt->second.end(), line, "unexpected attribute value <" + v + "> in attribute <" + a.first + ">" );
        }
      }
    }
  }
}

void checkElements( int                                               line,
                    std::vector<tinyxml2::XMLElement const *> const & elements,
                    std::map<std::string, bool> const &               required,
                    std::set<std::string> const &                     optional )
{
  std::map<std::string, size_t> encountered;
  for ( auto const & e : elements )
  {
    std::string value = e->Value();
    encountered[value]++;
    checkForWarning(
      ( required.find( value ) != required.end() ) || ( optional.find( value ) != optional.end() ), e->GetLineNum(), "unknown element <" + value + ">" );
  }
  for ( auto const & r : required )
  {
    auto encounteredIt = encountered.find( r.first );
    checkForError( encounteredIt != encountered.end(), line, "missing required element <" + r.first + ">" );
    // check: r.second (means: required excactly once) => (encouteredIt->second == 1)
    checkForError( !r.second || ( encounteredIt->second == 1 ),
                   line,
                   "required element <" + r.first + "> is supposed to be listed exactly once, but is listed " + std::to_string( encounteredIt->second ) );
  }
}

void checkForError( bool condition, int line, std::string const & message )
{
  if ( !condition )
  {
    throw std::runtime_error( "VulkanHppGenerator: Spec error on line " + std::to_string( line ) + ": " + message );
  }
}

void checkForWarning( bool condition, int line, std::string const & message )
{
  if ( !condition )
  {
    std::cerr << "VulkanHppGenerator: Spec warning on line " << std::to_string( line ) << ": " << message << "!" << std::endl;
  }
}

template <class InputIt, class UnaryPredicate>
std::vector<InputIt> findAll( InputIt first, InputIt last, UnaryPredicate p )
{
  std::vector<InputIt> result;
  while ( first != last )
  {
    if ( p( *first ) )
    {
      result.push_back( first );
    }
    ++first;
  }
  return result;
}

std::string findTag( std::set<std::string> const & tags, std::string const & name, std::string const & postfix )
{
  auto tagIt = std::find_if( tags.begin(), tags.end(), [&name, &postfix]( std::string const & t ) { return name.ends_with( t + postfix ); } );
  return ( tagIt != tags.end() ) ? *tagIt : "";
}

std::string generateCArraySizes( std::vector<std::string> const & sizes )
{
  std::string arraySizes;
  for ( auto const & s : sizes )
  {
    arraySizes += "[" + s + "]";
  }
  return arraySizes;
}

std::pair<std::string, std::string> generateEnumSuffixes( std::string const & name, bool bitmask, std::set<std::string> const & tags )
{
  std::string prefix, postfix;
  if ( name == "VkResult" )
  {
    prefix = "VK_";
  }
  else
  {
    if ( bitmask )
    {
      // for a bitmask enum, start with "VK", cut off the trailing "FlagBits", and convert that name to upper case
      // end that with "Bit"
      size_t pos = name.find( "FlagBits" );
      assert( pos != std::string::npos );
      std::string shortenedName = name;
      shortenedName.erase( pos, strlen( "FlagBits" ) );
      std::string tag = findTag( tags, shortenedName );
      prefix          = toUpperCase( stripPostfix( shortenedName, tag ) ) + "_";
    }
    else
    {
      // for a non-bitmask enum, convert the name to upper case
      prefix = toUpperCase( name ) + "_";
    }

    // if the enum name contains a tag move it from the prefix to the postfix to generate correct enum value
    // names.
    for ( auto const & tag : tags )
    {
      if ( prefix.ends_with( tag + "_" ) )
      {
        prefix.erase( prefix.length() - tag.length() - 1 );
        postfix = "_" + tag;
        break;
      }
      else if ( name.ends_with( tag ) )
      {
        postfix = "_" + tag;
        break;
      }
    }
  }

  return std::make_pair( prefix, postfix );
}

std::string generateEnumValueName( std::string const & enumName, std::string const & valueName, bool bitmask, std::set<std::string> const & tags )
{
  std::string prefix, postfix;
  std::tie( prefix, postfix ) = generateEnumSuffixes( enumName, bitmask, tags );
  std::string tag             = findTag( tags, valueName, "" );
  if ( postfix == "_" + tag )
  {
    tag = findTag( tags, valueName, postfix );
  }

  std::string result = "e" + toCamelCase( stripPostfix( stripPrefix( valueName, prefix ), postfix ) );
  if ( bitmask )
  {
    size_t pos = result.find( "Bit" );
    if ( pos != std::string::npos )
    {
      result.erase( pos, 3 );
    }
  }
  if ( !tag.empty() && ( result.substr( result.length() - tag.length() ) == toCamelCase( tag ) ) )
  {
    result = result.substr( 0, result.length() - tag.length() ) + tag;
  }
  return result;
}

std::string generateNamespacedType( std::string const & type )
{
  return type.starts_with( "Vk" ) ? ( "VULKAN_HPP_NAMESPACE::" + stripPrefix( type, "Vk" ) ) : type;
}

std::string generateNoDiscard( bool returnsSomething, bool multiSuccessCodes, bool multiErrorCodes )
{
  return ( returnsSomething || multiSuccessCodes ) ? "VULKAN_HPP_NODISCARD " : ( multiErrorCodes ? "VULKAN_HPP_NODISCARD_WHEN_NO_EXCEPTIONS " : "" );
}

std::string generateStandardArray( std::string const & type, std::vector<std::string> const & sizes )
{
  std::string arrayString = "std::array<" + type + "," + sizes.back() + ">";
  for ( size_t i = sizes.size() - 2; i < sizes.size(); i-- )
  {
    arrayString = "std::array<" + arrayString + "," + sizes[i] + ">";
  }
  return arrayString;
}

std::string generateStandardArrayWrapper( std::string const & type, std::vector<std::string> const & sizes )
{
  std::string arrayString = "VULKAN_HPP_NAMESPACE::ArrayWrapper" + std::to_string( sizes.size() ) + "D<" + type;
  for ( auto const & size : sizes )
  {
    arrayString += ", " + size;
  }
  arrayString += ">";
  return arrayString;
}

std::string generateSuccessCode( std::string const & code, std::set<std::string> const & tags )
{
  std::string tag = findTag( tags, code );
  // on each success code: prepend 'VULKAN_HPP_NAMESPACE::Result::e', strip "VK_" and a tag, convert it to camel
  // case, and add the tag again
  return "VULKAN_HPP_NAMESPACE::Result::e" + toCamelCase( stripPostfix( stripPrefix( code, "VK_" ), tag ) ) + tag;
}

std::map<std::string, std::string> getAttributes( tinyxml2::XMLElement const * element )
{
  std::map<std::string, std::string> attributes;
  for ( auto attribute = element->FirstAttribute(); attribute; attribute = attribute->Next() )
  {
    assert( attributes.find( attribute->Name() ) == attributes.end() );
    attributes[attribute->Name()] = attribute->Value();
  }
  return attributes;
}

template <typename ElementContainer>
std::vector<tinyxml2::XMLElement const *> getChildElements( ElementContainer const * element )
{
  std::vector<tinyxml2::XMLElement const *> childElements;
  for ( tinyxml2::XMLElement const * childElement = element->FirstChildElement(); childElement; childElement = childElement->NextSiblingElement() )
  {
    childElements.push_back( childElement );
  }
  return childElements;
}

std::pair<std::vector<std::string>, std::string> readModifiers( tinyxml2::XMLNode const * node )
{
  std::vector<std::string> arraySizes;
  std::string              bitCount;
  if ( node && node->ToText() )
  {
    // following the name there might be some array size
    std::string value = node->Value();
    assert( !value.empty() );
    if ( value[0] == '[' )
    {
      std::string::size_type endPos = 0;
      while ( endPos + 1 != value.length() )
      {
        std::string::size_type startPos = value.find( '[', endPos );
        checkForError( startPos != std::string::npos, node->GetLineNum(), "could not find '[' in <" + value + ">" );
        endPos = value.find( ']', startPos );
        checkForError( endPos != std::string::npos, node->GetLineNum(), "could not find ']' in <" + value + ">" );
        checkForError( startPos + 2 <= endPos, node->GetLineNum(), "missing content between '[' and ']' in <" + value + ">" );
        arraySizes.push_back( value.substr( startPos + 1, endPos - startPos - 1 ) );
      }
    }
    else if ( value[0] == ':' )
    {
      bitCount = value.substr( 1 );
    }
    else
    {
      checkForError( ( value[0] == ';' ) || ( value[0] == ')' ), node->GetLineNum(), "unknown modifier <" + value + ">" );
    }
  }
  return std::make_pair( arraySizes, bitCount );
}

std::string readSnippet( std::string const & snippetFile )
{
  std::ifstream ifs( std::string( BASE_PATH ) + "/snippets/" + snippetFile );
  assert( !ifs.fail() );
  std::ostringstream oss;
  oss << ifs.rdbuf();
  return oss.str();
}

std::string replaceWithMap( std::string const & input, std::map<std::string, std::string> replacements )
{
  // This will match ${someVariable} and contain someVariable in match group 1
  std::regex re( R"(\$\{([^\}]+)\})" );
  auto       it  = std::sregex_iterator( input.begin(), input.end(), re );
  auto       end = std::sregex_iterator();

  // No match, just return the original string
  if ( it == end )
  {
    assert( replacements.empty() );
    return input;
  }

#if !defined( NDEBUG )
  std::set<std::string> matchedReplacements;
#endif

  std::string result = "";
  while ( it != end )
  {
    std::smatch match         = *it;
    auto        itReplacement = replacements.find( match[1].str() );
    assert( itReplacement != replacements.end() );
#if !defined( NDEBUG )
    matchedReplacements.insert( match[1].str() );
#endif

    result += match.prefix().str() + ( ( itReplacement != replacements.end() ) ? itReplacement->second : match[0].str() );
    ++it;

    // we've passed the last match. Append the rest of the orignal string
    if ( it == end )
    {
      result += match.suffix().str();
    }
  }
#if !defined( NDEBUG )
  std::set<std::string> missedReplacements;
  for ( auto r : replacements )
  {
    if ( matchedReplacements.find( r.first ) == matchedReplacements.end() )
    {
      missedReplacements.insert( r.first );
    }
  }
  assert( missedReplacements.empty() );
#endif
  return result;
}

std::string startLowerCase( std::string const & input )
{
  assert( !input.empty() );
  return static_cast<char>( tolower( input[0] ) ) + input.substr( 1 );
}

std::string startUpperCase( std::string const & input )
{
  assert( !input.empty() );
  return static_cast<char>( toupper( input[0] ) ) + input.substr( 1 );
}

std::string stripPostfix( std::string const & value, std::string const & postfix )
{
  std::string strippedValue = value;
  if ( strippedValue.ends_with( postfix ) )
  {
    strippedValue.erase( strippedValue.length() - postfix.length() );
  }
  return strippedValue;
}

std::string stripPluralS( std::string const & name )
{
  std::string strippedName( name );
  size_t      pos = strippedName.rfind( 's' );
  if ( pos != std::string::npos )
  {
    if ( ( 2 <= pos ) && ( strippedName.substr( pos - 2, 3 ) == "ies" ) )
    {
      strippedName.replace( pos - 2, 3, "y" );
    }
    else
    {
      strippedName.erase( pos, 1 );
    }
  }
  return strippedName;
}

std::string stripPrefix( std::string const & value, std::string const & prefix )
{
  std::string strippedValue = value;
  if ( strippedValue.starts_with( prefix ) )
  {
    strippedValue.erase( 0, prefix.length() );
  }
  return strippedValue;
}

std::string toCamelCase( std::string const & value )
{
  assert( !value.empty() && ( isupper( value[0] ) || isdigit( value[0] ) ) );
  std::string result;
  result.reserve( value.size() );
  bool keepUpper = true;
  for ( auto c : value )
  {
    if ( c == '_' )
    {
      keepUpper = true;
    }
    else if ( isdigit( c ) )
    {
      keepUpper = true;
      result.push_back( c );
    }
    else if ( keepUpper )
    {
      result.push_back( c );
      keepUpper = false;
    }
    else
    {
      result.push_back( static_cast<char>( tolower( c ) ) );
    }
  }
  return result;
}

std::string toUpperCase( std::string const & name )
{
  std::string convertedName;
  bool        previousIsLowerCase = false;
  bool        previousIsDigit     = false;
  for ( auto c : name )
  {
    if ( ( isupper( c ) && ( previousIsLowerCase || previousIsDigit ) ) || ( isdigit( c ) && previousIsLowerCase ) )
    {
      convertedName.push_back( '_' );
    }
    convertedName.push_back( static_cast<char>( toupper( c ) ) );
    previousIsLowerCase = !!islower( c );
    previousIsDigit     = !!isdigit( c );
  }
  return convertedName;
}

std::vector<std::string> tokenize( std::string const & tokenString, std::string const & separator )
{
  std::vector<std::string> tokens;
  if ( !tokenString.empty() )
  {
    size_t start = 0, end;
    do
    {
      end = tokenString.find( separator, start );
      if ( start != end )
      {
        tokens.push_back( trim( tokenString.substr( start, end - start ) ) );
      }
      start = end + separator.length();
    } while ( end != std::string::npos );
  }
  return tokens;
}

std::string trim( std::string const & input )
{
  std::string result = input;
  result.erase( result.begin(), std::find_if( result.begin(), result.end(), []( char c ) { return !std::isspace( c ); } ) );
  result.erase( std::find_if( result.rbegin(), result.rend(), []( char c ) { return !std::isspace( c ); } ).base(), result.end() );
  return result;
}

std::string trimEnd( std::string const & input )
{
  std::string result = input;
  result.erase( std::find_if( result.rbegin(), result.rend(), []( char c ) { return !std::isspace( c ); } ).base(), result.end() );
  return result;
}

std::string trimStars( std::string const & input )
{
  std::string result = input;
  size_t      pos    = result.find( '*' );
  while ( pos != std::string::npos )
  {
    if ( ( 0 < pos ) && ( result[pos - 1] != ' ' ) && ( result[pos - 1] != '*' ) )
    {
      result.insert( pos, 1, ' ' );
      ++pos;
    }
    else if ( ( pos < result.length() - 1 ) && ( result[pos + 1] != ' ' ) && ( result[pos + 1] != '*' ) )
    {
      result.insert( pos + 1, 1, ' ' );
    }
    pos = result.find( '*', pos + 1 );
  }
  return result;
}

void writeToFile( std::string const & str, std::string const & fileName )
{
  std::ofstream ofs( fileName );
  assert( !ofs.fail() );
  ofs << str;
  ofs.close();

#if defined( CLANG_FORMAT_EXECUTABLE )
  std::cout << "VulkanHppGenerator: Formatting " << fileName << " ..." << std::endl;
  std::string commandString = "\"" CLANG_FORMAT_EXECUTABLE "\" -i --style=file " + fileName;
  int         ret           = std::system( commandString.c_str() );
  if ( ret != 0 )
  {
    std::cout << "VulkanHppGenerator: failed to format file " << fileName << " with error <" << ret << ">\n";
  }
#endif
}

std::string toString( tinyxml2::XMLError error )
{
  switch ( error )
  {
    case tinyxml2::XML_SUCCESS: return "XML_SUCCESS";
    case tinyxml2::XML_NO_ATTRIBUTE: return "XML_NO_ATTRIBUTE";
    case tinyxml2::XML_WRONG_ATTRIBUTE_TYPE: return "XML_WRONG_ATTRIBUTE_TYPE";
    case tinyxml2::XML_ERROR_FILE_NOT_FOUND: return "XML_ERROR_FILE_NOT_FOUND";
    case tinyxml2::XML_ERROR_FILE_COULD_NOT_BE_OPENED: return "XML_ERROR_FILE_COULD_NOT_BE_OPENED";
    case tinyxml2::XML_ERROR_FILE_READ_ERROR: return "XML_ERROR_FILE_READ_ERROR";
    case tinyxml2::XML_ERROR_PARSING_ELEMENT: return "XML_ERROR_PARSING_ELEMENT";
    case tinyxml2::XML_ERROR_PARSING_ATTRIBUTE: return "XML_ERROR_PARSING_ATTRIBUTE";
    case tinyxml2::XML_ERROR_PARSING_TEXT: return "XML_ERROR_PARSING_TEXT";
    case tinyxml2::XML_ERROR_PARSING_CDATA: return "XML_ERROR_PARSING_CDATA";
    case tinyxml2::XML_ERROR_PARSING_COMMENT: return "XML_ERROR_PARSING_COMMENT";
    case tinyxml2::XML_ERROR_PARSING_DECLARATION: return "XML_ERROR_PARSING_DECLARATION";
    case tinyxml2::XML_ERROR_PARSING_UNKNOWN: return "XML_ERROR_PARSING_UNKNOWN";
    case tinyxml2::XML_ERROR_EMPTY_DOCUMENT: return "XML_ERROR_EMPTY_DOCUMENT";
    case tinyxml2::XML_ERROR_MISMATCHED_ELEMENT: return "XML_ERROR_MISMATCHED_ELEMENT";
    case tinyxml2::XML_ERROR_PARSING: return "XML_ERROR_PARSING";
    case tinyxml2::XML_CAN_NOT_CONVERT_TEXT: return "XML_CAN_NOT_CONVERT_TEXT";
    case tinyxml2::XML_NO_TEXT_NODE: return "XML_NO_TEXT_NODE";
    default: return "unknown error code <" + std::to_string( error ) + ">";
  }
}

int main( int argc, char ** argv )
{
  try
  {
    tinyxml2::XMLDocument doc;

    std::string filename = ( argc == 1 ) ? VK_SPEC : argv[1];

#if defined( CLANG_FORMAT_EXECUTABLE )
    std::cout << "VulkanHppGenerator: Found ";
    std::string commandString = "\"" CLANG_FORMAT_EXECUTABLE "\" --version ";
    int         ret           = std::system( commandString.c_str() );
    if ( ret != 0 )
    {
      std::cout << "VulkanHppGenerator: failed to determine clang_format version with error <" << ret << ">\n";
    }
#endif

    std::cout << "VulkanHppGenerator: Loading " << filename << std::endl;
    tinyxml2::XMLError error = doc.LoadFile( filename.c_str() );
    if ( error != tinyxml2::XML_SUCCESS )
    {
      std::cout << "VulkanHppGenerator: failed to load file " << filename << " with error <" << toString( error ) << ">" << std::endl;
      return -1;
    }

    std::cout << "VulkanHppGenerator: Parsing " << filename << std::endl;
    VulkanHppGenerator generator( doc );

    generator.generateVulkanHppFile();
    generator.generateVulkanEnumsHppFile();
    generator.generateVulkanFormatTraitsHppFile();
    generator.generateVulkanFuncsHppFile();
    generator.generateVulkanHandlesHppFile();
    generator.generateVulkanHashHppFile();
    generator.prepareRAIIHandles();
    generator.generateVulkanRAIIHppFile();
    generator.generateVulkanStaticAssertionsHppFile();
    generator.generateVulkanStructsHppFile();
    generator.generateVulkanToStringHppFile();

#if !defined( CLANG_FORMAT_EXECUTABLE )
    std::cout << "VulkanHppGenerator: could not find clang-format. The generated files will not be formatted accordingly.\n";
#endif
  }
  catch ( std::exception const & e )
  {
    std::cout << "caught exception: " << e.what() << std::endl;
    return -1;
  }
  catch ( ... )
  {
    std::cout << "caught unknown exception" << std::endl;
    return -1;
  }
}