haraldwolff
/
json
mirror of https://github.com/nlohmann/json.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

♻️ do not unconditionally redefine C++14 constructs

pull/2533/head
Niels Lohmann 2020-12-14 14:31:27 +01:00
parent 2fc1f694ad
commit 467986fe98
No known key found for this signature in database
GPG Key ID: 7F3CEA63AE251B69
2 changed files with 41 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
include/nlohmann/detail/meta/cpp_future.hpp
View File

@ -2,19 +2,32 @@
#include <cstddef> // size_t
#include <type_traits> // conditional, enable_if, false_type, integral_constant, is_constructible, is_integral, is_same, remove_cv, remove_reference, true_type
#include <utility> // index_sequence, make_index_sequence, index_sequence_for
#include <nlohmann/detail/macro_scope.hpp>
namespace nlohmann
{
namespace detail
{
// alias templates to reduce boilerplate
template<bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
template<typename T>
using uncvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;
// implementation of C++14 index_sequence and affiliates
#ifdef JSON_HAS_CPP_14
// the following utilities are natively available in C++14
using std::enable_if_t;
using std::index_sequence;
using std::make_index_sequence;
using std::index_sequence_for;
#else
// alias templates to reduce boilerplate
template<bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
// source: https://stackoverflow.com/a/32223343
template<std::size_t... Ints>
struct index_sequence
@ -45,6 +58,8 @@ template<> struct make_index_sequence<1> : index_sequence<0> {};
template<typename... Ts>
using index_sequence_for = make_index_sequence<sizeof...(Ts)>;
#endif
// dispatch utility (taken from ranges-v3)
template<unsigned N> struct priority_tag : priority_tag < N - 1 > {};
template<> struct priority_tag<0> {};
@ -58,5 +73,6 @@ struct static_const
template<typename T>
constexpr T static_const<T>::value;
} // namespace detail
} // namespace nlohmann

25
single_include/nlohmann/json.hpp
View File

@ -2736,19 +2736,33 @@ class other_error : public exception
#include <cstddef> // size_t
#include <type_traits> // conditional, enable_if, false_type, integral_constant, is_constructible, is_integral, is_same, remove_cv, remove_reference, true_type
#include <utility> // index_sequence, make_index_sequence, index_sequence_for
// #include <nlohmann/detail/macro_scope.hpp>
namespace nlohmann
{
namespace detail
{
// alias templates to reduce boilerplate
template<bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
template<typename T>
using uncvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;
// implementation of C++14 index_sequence and affiliates
#ifdef JSON_HAS_CPP_14
// the following utilities are natively available in C++14
using std::enable_if_t;
using std::index_sequence;
using std::make_index_sequence;
using std::index_sequence_for;
#else
// alias templates to reduce boilerplate
template<bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
// source: https://stackoverflow.com/a/32223343
template<std::size_t... Ints>
struct index_sequence
@ -2779,6 +2793,8 @@ template<> struct make_index_sequence<1> : index_sequence<0> {};
template<typename... Ts>
using index_sequence_for = make_index_sequence<sizeof...(Ts)>;
#endif
// dispatch utility (taken from ranges-v3)
template<unsigned N> struct priority_tag : priority_tag < N - 1 > {};
template<> struct priority_tag<0> {};
@ -2792,6 +2808,7 @@ struct static_const
template<typename T>
constexpr T static_const<T>::value;
} // namespace detail
} // namespace nlohmann