Files
json/src/modules/json.cppm
T
Niels Lohmann 1419aeff60 Move the user-defined string literals to <nlohmann/json_literals.hpp>
Following the review in #5294, the literals now live in their own header
instead of being removed entirely: <nlohmann/json.hpp> includes it at the
end unless JSON_NO_AUTOMATIC_UDLS (renamed from JSON_NO_UDLS) is defined,
so a project can opt out globally and include the header only where the
literals are used.

The header only uses public and standard macros, because the library's
internal macros are undefined at the end of json.hpp and the amalgamation
inlines macro_scope.hpp only once. For the same reason, the library no
longer defines and undefines JSON_USE_GLOBAL_UDLS, so a user's definition
is still visible to the header. The single-header copy is identical to
the multi-header one, as it only includes <nlohmann/json.hpp>. The module
always exports the literals.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-09-28 21:49:37 +02:00

54 lines
1.9 KiB
C++

// __ _____ _____ _____
// __| | __| | | | JSON for Modern C++
// | | |__ | | | | | | version 3.12.0
// |_____|_____|_____|_|___| https://github.com/nlohmann/json
//
// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>
// SPDX-License-Identifier: MIT
module;
// GCC workaround for C++ modules support.
// When using C++20 modules, some compilers (particularly GCC) may have issues
// with template instantiations in the module preamble. If you encounter
// "redefinition" errors when including nlohmann/json.hpp, try one of:
// 1. Include nlohmann/json.hpp in your module preamble BEFORE other #includes
// 2. Or use: import nlohmann.json; instead of #include <nlohmann/json.hpp>
// 3. Or upgrade to a newer GCC version with better modules support.
// See: https://github.com/nlohmann/json/issues/5103
#include <nlohmann/json.hpp>
#include <nlohmann/json_literals.hpp>
export module nlohmann.json;
export
NLOHMANN_JSON_NAMESPACE_BEGIN
using NLOHMANN_JSON_NAMESPACE::adl_serializer;
using NLOHMANN_JSON_NAMESPACE::basic_json;
using NLOHMANN_JSON_NAMESPACE::json;
using NLOHMANN_JSON_NAMESPACE::json_pointer;
using NLOHMANN_JSON_NAMESPACE::ordered_json;
using NLOHMANN_JSON_NAMESPACE::ordered_map;
using NLOHMANN_JSON_NAMESPACE::to_string;
inline namespace literals
{
inline namespace json_literals
{
using NLOHMANN_JSON_NAMESPACE::literals::json_literals::operator""_json;
using NLOHMANN_JSON_NAMESPACE::literals::json_literals::operator""_json_pointer;
} // namespace json_literals
} // namespace literals
// Note: the following nlohmann::detail symbols must be exported due to
// an MSVC bug failing to compile without these symbols visible (ticket #3970)
namespace detail
{
using NLOHMANN_JSON_NAMESPACE::detail::json_sax_dom_callback_parser;
using NLOHMANN_JSON_NAMESPACE::detail::unknown_size;
} // namespace detail
NLOHMANN_JSON_NAMESPACE_END