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nlohmannjson/include/nlohmann/detail/conversions/to_json.hpp
2022-08-12 15:04:06 +02:00

447 lines
15 KiB
C++

// __ _____ _____ _____
// __| | __| | | | JSON for Modern C++
// | | |__ | | | | | | version 3.11.2
// |_____|_____|_____|_|___| https://github.com/nlohmann/json
//
// SPDX-FileCopyrightText: 2013-2022 Niels Lohmann <https://nlohmann.me>
// SPDX-License-Identifier: MIT
#pragma once
#include <algorithm> // copy
#include <iterator> // begin, end
#include <string> // string
#include <tuple> // tuple, get
#include <type_traits> // is_same, is_constructible, is_floating_point, is_enum, underlying_type
#include <utility> // move, forward, declval, pair
#include <valarray> // valarray
#include <vector> // vector
#include <nlohmann/detail/iterators/iteration_proxy.hpp>
#include <nlohmann/detail/macro_scope.hpp>
#include <nlohmann/detail/meta/cpp_future.hpp>
#include <nlohmann/detail/meta/std_fs.hpp>
#include <nlohmann/detail/meta/type_traits.hpp>
#include <nlohmann/detail/value_t.hpp>
NLOHMANN_JSON_NAMESPACE_BEGIN
namespace detail
{
//////////////////
// constructors //
//////////////////
/*
* Note all external_constructor<>::construct functions need to call
* j.m_value.destroy(j.m_type) to avoid a memory leak in case j contains an
* allocated value (e.g., a string). See bug issue
* https://github.com/nlohmann/json/issues/2865 for more information.
*/
template<value_t> struct external_constructor;
template<>
struct external_constructor<value_t::boolean>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::boolean_t b) noexcept
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::boolean;
j.m_value = b;
j.assert_invariant();
}
};
template<>
struct external_constructor<value_t::string>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::string;
j.m_value = s;
j.assert_invariant();
}
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::string_t&& s)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::string;
j.m_value = std::move(s);
j.assert_invariant();
}
template < typename BasicJsonType, typename CompatibleStringType,
enable_if_t < !std::is_same<CompatibleStringType, typename BasicJsonType::string_t>::value,
int > = 0 >
static void construct(BasicJsonType& j, const CompatibleStringType& str)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::string;
j.m_value.string = j.template create<typename BasicJsonType::string_t>(str);
j.assert_invariant();
}
};
template<>
struct external_constructor<value_t::binary>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, const typename BasicJsonType::binary_t& b)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::binary;
j.m_value = typename BasicJsonType::binary_t(b);
j.assert_invariant();
}
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::binary_t&& b)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::binary;
j.m_value = typename BasicJsonType::binary_t(std::move(b));
j.assert_invariant();
}
};
template<>
struct external_constructor<value_t::number_float>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::number_float_t val) noexcept
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::number_float;
j.m_value = val;
j.assert_invariant();
}
};
template<>
struct external_constructor<value_t::number_unsigned>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::number_unsigned_t val) noexcept
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::number_unsigned;
j.m_value = val;
j.assert_invariant();
}
};
template<>
struct external_constructor<value_t::number_integer>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::number_integer_t val) noexcept
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::number_integer;
j.m_value = val;
j.assert_invariant();
}
};
template<>
struct external_constructor<value_t::array>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::array;
j.m_value = arr;
j.set_parents();
j.assert_invariant();
}
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::array;
j.m_value = std::move(arr);
j.set_parents();
j.assert_invariant();
}
template < typename BasicJsonType, typename CompatibleArrayType,
enable_if_t < !std::is_same<CompatibleArrayType, typename BasicJsonType::array_t>::value,
int > = 0 >
static void construct(BasicJsonType& j, const CompatibleArrayType& arr)
{
using std::begin;
using std::end;
j.m_value.destroy(j.m_type);
j.m_type = value_t::array;
j.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
j.set_parents();
j.assert_invariant();
}
template<typename BasicJsonType>
static void construct(BasicJsonType& j, const std::vector<bool>& arr)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::array;
j.m_value = value_t::array;
j.m_value.array->reserve(arr.size());
for (const bool x : arr)
{
j.m_value.array->push_back(x);
j.set_parent(j.m_value.array->back());
}
j.assert_invariant();
}
template<typename BasicJsonType, typename T,
enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
static void construct(BasicJsonType& j, const std::valarray<T>& arr)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::array;
j.m_value = value_t::array;
j.m_value.array->resize(arr.size());
if (arr.size() > 0)
{
std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
}
j.set_parents();
j.assert_invariant();
}
};
template<>
struct external_constructor<value_t::object>
{
template<typename BasicJsonType>
static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::object;
j.m_value = obj;
j.set_parents();
j.assert_invariant();
}
template<typename BasicJsonType>
static void construct(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
{
j.m_value.destroy(j.m_type);
j.m_type = value_t::object;
j.m_value = std::move(obj);
j.set_parents();
j.assert_invariant();
}
template < typename BasicJsonType, typename CompatibleObjectType,
enable_if_t < !std::is_same<CompatibleObjectType, typename BasicJsonType::object_t>::value, int > = 0 >
static void construct(BasicJsonType& j, const CompatibleObjectType& obj)
{
using std::begin;
using std::end;
j.m_value.destroy(j.m_type);
j.m_type = value_t::object;
j.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
j.set_parents();
j.assert_invariant();
}
};
/////////////
// to_json //
/////////////
template<typename BasicJsonType, typename T,
enable_if_t<std::is_same<T, typename BasicJsonType::boolean_t>::value, int> = 0>
inline void to_json(BasicJsonType& j, T b) noexcept
{
external_constructor<value_t::boolean>::construct(j, b);
}
template < typename BasicJsonType, typename BoolRef,
enable_if_t <
((std::is_same<std::vector<bool>::reference, BoolRef>::value
&& !std::is_same <std::vector<bool>::reference, typename BasicJsonType::boolean_t&>::value)
|| (std::is_same<std::vector<bool>::const_reference, BoolRef>::value
&& !std::is_same <detail::uncvref_t<std::vector<bool>::const_reference>,
typename BasicJsonType::boolean_t >::value))
&& std::is_convertible<const BoolRef&, typename BasicJsonType::boolean_t>::value, int > = 0 >
inline void to_json(BasicJsonType& j, const BoolRef& b) noexcept
{
external_constructor<value_t::boolean>::construct(j, static_cast<typename BasicJsonType::boolean_t>(b));
}
template<typename BasicJsonType, typename CompatibleString,
enable_if_t<std::is_constructible<typename BasicJsonType::string_t, CompatibleString>::value, int> = 0>
inline void to_json(BasicJsonType& j, const CompatibleString& s)
{
external_constructor<value_t::string>::construct(j, s);
}
template<typename BasicJsonType>
inline void to_json(BasicJsonType& j, typename BasicJsonType::string_t&& s)
{
external_constructor<value_t::string>::construct(j, std::move(s));
}
template<typename BasicJsonType, typename FloatType,
enable_if_t<std::is_floating_point<FloatType>::value, int> = 0>
inline void to_json(BasicJsonType& j, FloatType val) noexcept
{
external_constructor<value_t::number_float>::construct(j, static_cast<typename BasicJsonType::number_float_t>(val));
}
template<typename BasicJsonType, typename CompatibleNumberUnsignedType,
enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_unsigned_t, CompatibleNumberUnsignedType>::value, int> = 0>
inline void to_json(BasicJsonType& j, CompatibleNumberUnsignedType val) noexcept
{
external_constructor<value_t::number_unsigned>::construct(j, static_cast<typename BasicJsonType::number_unsigned_t>(val));
}
template<typename BasicJsonType, typename CompatibleNumberIntegerType,
enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_integer_t, CompatibleNumberIntegerType>::value, int> = 0>
inline void to_json(BasicJsonType& j, CompatibleNumberIntegerType val) noexcept
{
external_constructor<value_t::number_integer>::construct(j, static_cast<typename BasicJsonType::number_integer_t>(val));
}
#if !JSON_DISABLE_ENUM_SERIALIZATION
template<typename BasicJsonType, typename EnumType,
enable_if_t<std::is_enum<EnumType>::value, int> = 0>
inline void to_json(BasicJsonType& j, EnumType e) noexcept
{
using underlying_type = typename std::underlying_type<EnumType>::type;
external_constructor<value_t::number_integer>::construct(j, static_cast<underlying_type>(e));
}
#endif // JSON_DISABLE_ENUM_SERIALIZATION
template<typename BasicJsonType>
inline void to_json(BasicJsonType& j, const std::vector<bool>& e)
{
external_constructor<value_t::array>::construct(j, e);
}
template < typename BasicJsonType, typename CompatibleArrayType,
enable_if_t < is_compatible_array_type<BasicJsonType,
CompatibleArrayType>::value&&
!is_compatible_object_type<BasicJsonType, CompatibleArrayType>::value&&
!is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value&&
!std::is_same<typename BasicJsonType::binary_t, CompatibleArrayType>::value&&
!is_basic_json<CompatibleArrayType>::value,
int > = 0 >
inline void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
{
external_constructor<value_t::array>::construct(j, arr);
}
template<typename BasicJsonType>
inline void to_json(BasicJsonType& j, const typename BasicJsonType::binary_t& bin)
{
external_constructor<value_t::binary>::construct(j, bin);
}
template<typename BasicJsonType, typename T,
enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
inline void to_json(BasicJsonType& j, const std::valarray<T>& arr)
{
external_constructor<value_t::array>::construct(j, std::move(arr));
}
template<typename BasicJsonType>
inline void to_json(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
{
external_constructor<value_t::array>::construct(j, std::move(arr));
}
template < typename BasicJsonType, typename CompatibleObjectType,
enable_if_t < is_compatible_object_type<BasicJsonType, CompatibleObjectType>::value&& !is_basic_json<CompatibleObjectType>::value, int > = 0 >
inline void to_json(BasicJsonType& j, const CompatibleObjectType& obj)
{
external_constructor<value_t::object>::construct(j, obj);
}
template<typename BasicJsonType>
inline void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
{
external_constructor<value_t::object>::construct(j, std::move(obj));
}
template <
typename BasicJsonType, typename T, std::size_t N,
enable_if_t < !std::is_constructible<typename BasicJsonType::string_t,
const T(&)[N]>::value, // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
int > = 0 >
inline void to_json(BasicJsonType& j, const T(&arr)[N]) // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
{
external_constructor<value_t::array>::construct(j, arr);
}
template < typename BasicJsonType, typename T1, typename T2, enable_if_t < std::is_constructible<BasicJsonType, T1>::value&& std::is_constructible<BasicJsonType, T2>::value, int > = 0 >
inline void to_json(BasicJsonType& j, const std::pair<T1, T2>& p)
{
j = { p.first, p.second };
}
// for https://github.com/nlohmann/json/pull/1134
template<typename BasicJsonType, typename T,
enable_if_t<std::is_same<T, iteration_proxy_value<typename BasicJsonType::iterator>>::value, int> = 0>
inline void to_json(BasicJsonType& j, const T& b)
{
j = { {b.key(), b.value()} };
}
template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<Idx...> /*unused*/)
{
j = { std::get<Idx>(t)... };
}
template<typename BasicJsonType, typename T, enable_if_t<is_constructible_tuple<BasicJsonType, T>::value, int > = 0>
inline void to_json(BasicJsonType& j, const T& t)
{
to_json_tuple_impl(j, t, make_index_sequence<std::tuple_size<T>::value> {});
}
#if JSON_HAS_FILESYSTEM || JSON_HAS_EXPERIMENTAL_FILESYSTEM
template<typename BasicJsonType>
inline void to_json(BasicJsonType& j, const std_fs::path& p)
{
j = p.string();
}
#endif
struct to_json_fn
{
template<typename BasicJsonType, typename T>
auto operator()(BasicJsonType& j, T&& val) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
-> decltype(to_json(j, std::forward<T>(val)), void())
{
return to_json(j, std::forward<T>(val));
}
};
} // namespace detail
#ifndef JSON_HAS_CPP_17
/// namespace to hold default `to_json` function
/// to see why this is required:
/// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4381.html
namespace // NOLINT(cert-dcl59-cpp,fuchsia-header-anon-namespaces,google-build-namespaces)
{
#endif
JSON_INLINE_VARIABLE constexpr const auto& to_json = // NOLINT(misc-definitions-in-headers)
detail::static_const<detail::to_json_fn>::value;
#ifndef JSON_HAS_CPP_17
} // namespace
#endif
NLOHMANN_JSON_NAMESPACE_END