json/include/nlohmann/detail/json_custom_base_class.hpp
Raphael Grimm bed648ca55
Allow custom base class as node customization point (#3110)
Co-authored-by: Niels Lohmann <niels.lohmann@gmail.com>
Co-authored-by: Florian Albrechtskirchinger <falbrechtskirchinger@gmail.com>
Co-authored-by: barcode <barcode@example.com>
2022-08-28 13:59:07 +02:00

32 lines
883 B
C++

#pragma once
#include <type_traits> // conditional, is_same
#include <nlohmann/detail/abi_macros.hpp>
NLOHMANN_JSON_NAMESPACE_BEGIN
namespace detail
{
/*!
@brief Default base class of the @ref basic_json class.
So that the correct implementations of the copy / move ctors / assign operators
of @ref basic_json do not require complex case distinctions
(no base class / custom base class used as customization point),
@ref basic_json always has a base class.
By default, this class is used because it is empty and thus has no effect
on the behavior of @ref basic_json.
*/
struct json_default_base {};
template<class T>
using json_base_class = typename std::conditional <
std::is_same<T, void>::value,
json_default_base,
T
>::type;
} // namespace detail
NLOHMANN_JSON_NAMESPACE_END