Horizon
Loading...
Searching...
No Matches
detected.hpp
1#pragma once
2
3#include <type_traits>
4
5#include <nlohmann/detail/meta/void_t.hpp>
6
7// https://en.cppreference.com/w/cpp/experimental/is_detected
8namespace nlohmann
9{
10namespace detail
11{
13{
14 nonesuch() = delete;
15 ~nonesuch() = delete;
16 nonesuch(nonesuch const&) = delete;
17 nonesuch(nonesuch const&&) = delete;
18 void operator=(nonesuch const&) = delete;
19 void operator=(nonesuch&&) = delete;
20};
21
22template<class Default,
23 class AlwaysVoid,
24 template<class...> class Op,
25 class... Args>
27{
28 using value_t = std::false_type;
29 using type = Default;
30};
31
32template<class Default, template<class...> class Op, class... Args>
33struct detector<Default, void_t<Op<Args...>>, Op, Args...>
34{
35 using value_t = std::true_type;
36 using type = Op<Args...>;
37};
38
39template<template<class...> class Op, class... Args>
40using is_detected = typename detector<nonesuch, void, Op, Args...>::value_t;
41
42template<template<class...> class Op, class... Args>
43struct is_detected_lazy : is_detected<Op, Args...> { };
44
45template<template<class...> class Op, class... Args>
46using detected_t = typename detector<nonesuch, void, Op, Args...>::type;
47
48template<class Default, template<class...> class Op, class... Args>
49using detected_or = detector<Default, void, Op, Args...>;
50
51template<class Default, template<class...> class Op, class... Args>
52using detected_or_t = typename detected_or<Default, Op, Args...>::type;
53
54template<class Expected, template<class...> class Op, class... Args>
55using is_detected_exact = std::is_same<Expected, detected_t<Op, Args...>>;
56
57template<class To, template<class...> class Op, class... Args>
58using is_detected_convertible =
59 std::is_convertible<detected_t<Op, Args...>, To>;
60} // namespace detail
61} // namespace nlohmann
value_t
the JSON type enumeration
Definition value_t.hpp:41
namespace for Niels Lohmann
Definition adl_serializer.hpp:12
Definition detected.hpp:27
Definition detected.hpp:43
Definition detected.hpp:13