libstdc++
experimental/type_traits
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1// Variable Templates For Type Traits -*- C++ -*-
2
3// Copyright (C) 2014-2021 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file experimental/type_traits
26 * This is a TS C++ Library header.
27 *
28 * This header defines variable templates for the C++14 type traits.
29 *
30 * Equivalent variable templates are defined in namespace `std` since C++17.
31 * @see variable_templates
32 *
33 * @ingroup libfund-ts
34 * @since C++14
35 */
36
37//
38// N3932 Variable Templates For Type Traits (Revision 1)
39//
40
41#ifndef _GLIBCXX_EXPERIMENTAL_TYPE_TRAITS
42#define _GLIBCXX_EXPERIMENTAL_TYPE_TRAITS 1
43
44#pragma GCC system_header
45
46#if __cplusplus >= 201402L
47
48#include <type_traits>
49#include <experimental/bits/lfts_config.h>
50
51namespace std _GLIBCXX_VISIBILITY(default)
52{
53_GLIBCXX_BEGIN_NAMESPACE_VERSION
54
55namespace experimental
56{
57inline namespace fundamentals_v1
58{
59/** @defgroup lfts_variable_templates Variable template for type traits
60 * @ingroup libfund-ts
61 * @since Library Fundamentals TS v1. C++14.
62 * @see variable_templates
63 */
64/** @ingroup lfts_variable_templates
65 * @{
66 */
67#define __cpp_lib_experimental_type_trait_variable_templates 201402
68
69// See C++14 20.10.4.1, primary type categories
70template <typename _Tp>
71 constexpr bool is_void_v = is_void<_Tp>::value;
72template <typename _Tp>
73 constexpr bool is_null_pointer_v = is_null_pointer<_Tp>::value;
74template <typename _Tp>
75 constexpr bool is_integral_v = is_integral<_Tp>::value;
76template <typename _Tp>
77 constexpr bool is_floating_point_v = is_floating_point<_Tp>::value;
78template <typename _Tp>
79 constexpr bool is_array_v = is_array<_Tp>::value;
80template <typename _Tp>
81 constexpr bool is_pointer_v = is_pointer<_Tp>::value;
82template <typename _Tp>
83 constexpr bool is_lvalue_reference_v = is_lvalue_reference<_Tp>::value;
84template <typename _Tp>
85 constexpr bool is_rvalue_reference_v = is_rvalue_reference<_Tp>::value;
86template <typename _Tp>
87 constexpr bool is_member_object_pointer_v =
88 is_member_object_pointer<_Tp>::value;
89template <typename _Tp>
90 constexpr bool is_member_function_pointer_v =
91 is_member_function_pointer<_Tp>::value;
92template <typename _Tp>
93 constexpr bool is_enum_v = is_enum<_Tp>::value;
94template <typename _Tp>
95 constexpr bool is_union_v = is_union<_Tp>::value;
96template <typename _Tp>
97 constexpr bool is_class_v = is_class<_Tp>::value;
98template <typename _Tp>
99 constexpr bool is_function_v = is_function<_Tp>::value;
100
101// See C++14 20.10.4.2, composite type categories
102template <typename _Tp>
103 constexpr bool is_reference_v = is_reference<_Tp>::value;
104template <typename _Tp>
105 constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value;
106template <typename _Tp>
107 constexpr bool is_fundamental_v = is_fundamental<_Tp>::value;
108template <typename _Tp>
109 constexpr bool is_object_v = is_object<_Tp>::value;
110template <typename _Tp>
111 constexpr bool is_scalar_v = is_scalar<_Tp>::value;
112template <typename _Tp>
113 constexpr bool is_compound_v = is_compound<_Tp>::value;
114template <typename _Tp>
115 constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value;
116
117// See C++14 20.10.4.3, type properties
118template <typename _Tp>
119 constexpr bool is_const_v = is_const<_Tp>::value;
120template <typename _Tp>
121 constexpr bool is_volatile_v = is_volatile<_Tp>::value;
122template <typename _Tp>
123 constexpr bool is_trivial_v = is_trivial<_Tp>::value;
124template <typename _Tp>
125 constexpr bool is_trivially_copyable_v = is_trivially_copyable<_Tp>::value;
126template <typename _Tp>
127 constexpr bool is_standard_layout_v = is_standard_layout<_Tp>::value;
128#pragma GCC diagnostic push
129#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
130template <typename _Tp>
131 constexpr bool is_pod_v = is_pod<_Tp>::value;
132template <typename _Tp>
133 constexpr bool is_literal_type_v = is_literal_type<_Tp>::value;
134#pragma GCC diagnostic pop
135template <typename _Tp>
136 constexpr bool is_empty_v = is_empty<_Tp>::value;
137template <typename _Tp>
138 constexpr bool is_polymorphic_v = is_polymorphic<_Tp>::value;
139template <typename _Tp>
140 constexpr bool is_abstract_v = is_abstract<_Tp>::value;
141template <typename _Tp>
142 constexpr bool is_final_v = is_final<_Tp>::value;
143template <typename _Tp>
144 constexpr bool is_signed_v = is_signed<_Tp>::value;
145template <typename _Tp>
146 constexpr bool is_unsigned_v = is_unsigned<_Tp>::value;
147template <typename _Tp, typename... _Args>
148 constexpr bool is_constructible_v = is_constructible<_Tp, _Args...>::value;
149template <typename _Tp>
150 constexpr bool is_default_constructible_v =
151 is_default_constructible<_Tp>::value;
152template <typename _Tp>
153 constexpr bool is_copy_constructible_v = is_copy_constructible<_Tp>::value;
154template <typename _Tp>
155 constexpr bool is_move_constructible_v = is_move_constructible<_Tp>::value;
156template <typename _Tp, typename _Up>
157 constexpr bool is_assignable_v = is_assignable<_Tp, _Up>::value;
158template <typename _Tp>
159 constexpr bool is_copy_assignable_v = is_copy_assignable<_Tp>::value;
160template <typename _Tp>
161 constexpr bool is_move_assignable_v = is_move_assignable<_Tp>::value;
162template <typename _Tp>
163 constexpr bool is_destructible_v = is_destructible<_Tp>::value;
164template <typename _Tp, typename... _Args>
165 constexpr bool is_trivially_constructible_v =
166 is_trivially_constructible<_Tp, _Args...>::value;
167template <typename _Tp>
168 constexpr bool is_trivially_default_constructible_v =
169 is_trivially_default_constructible<_Tp>::value;
170template <typename _Tp>
171 constexpr bool is_trivially_copy_constructible_v =
172 is_trivially_copy_constructible<_Tp>::value;
173template <typename _Tp>
174 constexpr bool is_trivially_move_constructible_v =
175 is_trivially_move_constructible<_Tp>::value;
176template <typename _Tp, typename _Up>
177 constexpr bool is_trivially_assignable_v =
178 is_trivially_assignable<_Tp, _Up>::value;
179template <typename _Tp>
180 constexpr bool is_trivially_copy_assignable_v =
181 is_trivially_copy_assignable<_Tp>::value;
182template <typename _Tp>
183 constexpr bool is_trivially_move_assignable_v =
184 is_trivially_move_assignable<_Tp>::value;
185template <typename _Tp>
186 constexpr bool is_trivially_destructible_v =
187 is_trivially_destructible<_Tp>::value;
188template <typename _Tp, typename... _Args>
189 constexpr bool is_nothrow_constructible_v =
190 is_nothrow_constructible<_Tp, _Args...>::value;
191template <typename _Tp>
192 constexpr bool is_nothrow_default_constructible_v =
193 is_nothrow_default_constructible<_Tp>::value;
194template <typename _Tp>
195 constexpr bool is_nothrow_copy_constructible_v =
196 is_nothrow_copy_constructible<_Tp>::value;
197template <typename _Tp>
198 constexpr bool is_nothrow_move_constructible_v =
199 is_nothrow_move_constructible<_Tp>::value;
200template <typename _Tp, typename _Up>
201 constexpr bool is_nothrow_assignable_v =
202 is_nothrow_assignable<_Tp, _Up>::value;
203template <typename _Tp>
204 constexpr bool is_nothrow_copy_assignable_v =
205 is_nothrow_copy_assignable<_Tp>::value;
206template <typename _Tp>
207 constexpr bool is_nothrow_move_assignable_v =
208 is_nothrow_move_assignable<_Tp>::value;
209template <typename _Tp>
210 constexpr bool is_nothrow_destructible_v =
211 is_nothrow_destructible<_Tp>::value;
212template <typename _Tp>
213 constexpr bool has_virtual_destructor_v =
214 has_virtual_destructor<_Tp>::value;
215
216// See C++14 20.10.5, type property queries
217template <typename _Tp>
218 constexpr size_t alignment_of_v = alignment_of<_Tp>::value;
219template <typename _Tp>
220 constexpr size_t rank_v = rank<_Tp>::value;
221template <typename _Tp, unsigned _Idx = 0>
222 constexpr size_t extent_v = extent<_Tp, _Idx>::value;
223
224// See C++14 20.10.6, type relations
225template <typename _Tp, typename _Up>
226 constexpr bool is_same_v = is_same<_Tp, _Up>::value;
227template <typename _Base, typename _Derived>
228 constexpr bool is_base_of_v = is_base_of<_Base, _Derived>::value;
229template <typename _From, typename _To>
230 constexpr bool is_convertible_v = is_convertible<_From, _To>::value;
231/// @}
232
233 // 3.3.2, Other type transformations
234 // invocation_type (still unimplemented)
235 // raw_invocation_type (still unimplemented)
236 // invocation_type_t (still unimplemented)
237 // raw_invocation_type_t (still unimplemented)
238} // namespace fundamentals_v1
239
240inline namespace fundamentals_v2
241{
242/**
243 * @defgroup lfts_detect Detection idiom
244 * @ingroup libfund-ts
245 * @since Library Fundamentals TS v2. C++14.
246 */
247/** @ingroup lfts_detect
248 * @{
249 */
250#define __cpp_lib_experimental_detect 201505
251
252// [meta.detect]
253
254/// A metafunction that always yields void, used for detecting valid types.
255template<typename...> using void_t = void;
256
257#pragma GCC diagnostic push
258#pragma GCC diagnostic ignored "-Wctor-dtor-privacy"
259/// @internal
260struct __nonesuchbase {};
261struct nonesuch : private __nonesuchbase
262{
263 ~nonesuch() = delete;
264 nonesuch(nonesuch const&) = delete;
265 void operator=(nonesuch const&) = delete;
266};
267#pragma GCC diagnostic pop
268
269template<template<typename...> class _Op, typename... _Args>
270 using is_detected
271 = typename std::__detector<nonesuch, void, _Op, _Args...>::value_t;
272
273template<template<typename...> class _Op, typename... _Args>
274 constexpr bool is_detected_v = is_detected<_Op, _Args...>::value;
275
276template<template<typename...> class _Op, typename... _Args>
277 using detected_t
278 = typename std::__detector<nonesuch, void, _Op, _Args...>::type;
279
280template<typename _Default, template<typename...> class _Op, typename... _Args>
281 using detected_or = std::__detected_or<_Default, _Op, _Args...>;
282
283template<typename _Default, template<typename...> class _Op, typename... _Args>
284 using detected_or_t = typename detected_or<_Default, _Op, _Args...>::type;
285
286template<typename _Expected, template<typename...> class _Op, typename... _Args>
287 using is_detected_exact = is_same<_Expected, detected_t<_Op, _Args...>>;
288
289template<typename _Expected, template<typename...> class _Op, typename... _Args>
290 constexpr bool is_detected_exact_v
291 = is_detected_exact<_Expected, _Op, _Args...>::value;
292
293template<typename _To, template<typename...> class _Op, typename... _Args>
294 using is_detected_convertible
295 = is_convertible<detected_t<_Op, _Args...>, _To>;
296
297template<typename _To, template<typename...> class _Op, typename... _Args>
298 constexpr bool is_detected_convertible_v
299 = is_detected_convertible<_To, _Op, _Args...>::value;
300/// @}
301
302/**
303 * @defgroup lfts_logical Logical operator traits
304 * @ingroup libfund-ts
305 * @since Library Fundamentals TS v2. C++14.
306 */
307/** @ingroup lfts_logical
308 * @{
309 */
310#define __cpp_lib_experimental_logical_traits 201511
311
312template<typename... _Bn>
313 struct conjunction
314 : __and_<_Bn...>
315 { };
316
317template<typename... _Bn>
318 struct disjunction
319 : __or_<_Bn...>
320 { };
321
322template<typename _Pp>
323 struct negation
324 : __not_<_Pp>
325 { };
326
327template<typename... _Bn>
328 constexpr bool conjunction_v
329 = conjunction<_Bn...>::value;
330
331template<typename... _Bn>
332 constexpr bool disjunction_v
333 = disjunction<_Bn...>::value;
334
335template<typename _Pp>
336 constexpr bool negation_v
337 = negation<_Pp>::value;
338/// @}
339} // namespace fundamentals_v2
340} // namespace experimental
341
342_GLIBCXX_END_NAMESPACE_VERSION
343} // namespace std
344
345#endif // __cplusplus <= 201103L
346
347#endif // _GLIBCXX_EXPERIMENTAL_TYPE_TRAITS