Vulkan-Hpp/snippets/ArrayProxyNoTemporaries.hpp

  template <typename T>
  class ArrayProxyNoTemporaries
  {
  public:
    VULKAN_HPP_CONSTEXPR ArrayProxyNoTemporaries() VULKAN_HPP_NOEXCEPT
      : m_count( 0 )
      , m_ptr( nullptr )
    {
    }

    VULKAN_HPP_CONSTEXPR ArrayProxyNoTemporaries( std::nullptr_t ) VULKAN_HPP_NOEXCEPT
      : m_count( 0 )
      , m_ptr( nullptr )
    {
    }

    template <typename B = T, typename std::enable_if<std::is_convertible<B, T>::value && std::is_lvalue_reference<B>::value, int>::type = 0>
    ArrayProxyNoTemporaries( B && value ) VULKAN_HPP_NOEXCEPT
      : m_count( 1 )
      , m_ptr( &value )
    {
    }

    ArrayProxyNoTemporaries( uint32_t count, T * ptr ) VULKAN_HPP_NOEXCEPT
      : m_count( count )
      , m_ptr( ptr )
    {
    }

    template <std::size_t C>
    ArrayProxyNoTemporaries( T ( &ptr )[C] ) VULKAN_HPP_NOEXCEPT
      : m_count( C )
      , m_ptr( ptr )
    {
    }

    template <std::size_t C>
    ArrayProxyNoTemporaries( T ( &&ptr )[C] ) = delete;

    // Any l-value reference with a .data() return type implicitly convertible to T*, and a .size() return type implicitly convertible to size_t.
    template <typename V,
              typename std::enable_if<!std::is_convertible<decltype( std::declval<V>().begin() ), T *>::value &&
                                        std::is_convertible<decltype( std::declval<V>().data() ), T *>::value &&
                                        std::is_convertible<decltype( std::declval<V>().size() ), std::size_t>::value && std::is_lvalue_reference<V>::value,
                                      int>::type = 0>
    ArrayProxyNoTemporaries( V && v ) VULKAN_HPP_NOEXCEPT
      : m_count( static_cast<uint32_t>( v.size() ) )
      , m_ptr( v.data() )
    {
    }

    // Any l-value reference with a .begin() return type implicitly convertible to T*, and a .size() return type implicitly convertible to size_t.
    template <typename V,
              typename std::enable_if<std::is_convertible<decltype( std::declval<V>().begin() ), T *>::value &&
                                        std::is_convertible<decltype( std::declval<V>().size() ), std::size_t>::value && std::is_lvalue_reference<V>::value,
                                      int>::type = 0>
    ArrayProxyNoTemporaries( V && v ) VULKAN_HPP_NOEXCEPT
      : m_count( static_cast<uint32_t>( v.size() ) )
      , m_ptr( v.begin() )
    {
    }

    const T * begin() const VULKAN_HPP_NOEXCEPT
    {
      return m_ptr;
    }

    const T * end() const VULKAN_HPP_NOEXCEPT
    {
      return m_ptr + m_count;
    }

    const T & front() const VULKAN_HPP_NOEXCEPT
    {
      VULKAN_HPP_ASSERT( m_count && m_ptr );
      return *m_ptr;
    }

    const T & back() const VULKAN_HPP_NOEXCEPT
    {
      VULKAN_HPP_ASSERT( m_count && m_ptr );
      return *( m_ptr + m_count - 1 );
    }

    bool empty() const VULKAN_HPP_NOEXCEPT
    {
      return ( m_count == 0 );
    }

    uint32_t size() const VULKAN_HPP_NOEXCEPT
    {
      return m_count;
    }

    T * data() const VULKAN_HPP_NOEXCEPT
    {
      return m_ptr;
    }

  private:
    uint32_t m_count;
    T *      m_ptr;
  };