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The C and C++ Include Header Files
cat -n /usr/include/c++/15/experimental/type_traits
1 // Variable Templates For Type Traits -*- C++ -*- 2 3 // Copyright (C) 2014-2025 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 #ifdef _GLIBCXX_SYSHDR 45 #pragma GCC system_header 46 #endif 47 48 #if __cplusplus >= 201402L 49 50 #include <type_traits> 51 #include <experimental/bits/lfts_config.h> 52 53 namespace std _GLIBCXX_VISIBILITY(default) 54 { 55 _GLIBCXX_BEGIN_NAMESPACE_VERSION 56 57 namespace experimental 58 { 59 inline namespace fundamentals_v1 60 { 61 /** @defgroup lfts_variable_templates Variable template for type traits 62 * @ingroup libfund-ts 63 * @since Library Fundamentals TS v1. C++14. 64 * @see variable_templates 65 */ 66 /** @ingroup lfts_variable_templates 67 * @{ 68 */ 69 #define __cpp_lib_experimental_type_trait_variable_templates 201402 70 71 // See C++14 20.10.4.1, primary type categories 72 template <typename _Tp> 73 constexpr bool is_void_v = is_void<_Tp>::value; 74 template <typename _Tp> 75 constexpr bool is_null_pointer_v = is_null_pointer<_Tp>::value; 76 template <typename _Tp> 77 constexpr bool is_integral_v = is_integral<_Tp>::value; 78 template <typename _Tp> 79 constexpr bool is_floating_point_v = is_floating_point<_Tp>::value; 80 template <typename _Tp> 81 constexpr bool is_array_v = is_array<_Tp>::value; 82 template <typename _Tp> 83 constexpr bool is_pointer_v = is_pointer<_Tp>::value; 84 template <typename _Tp> 85 constexpr bool is_lvalue_reference_v = is_lvalue_reference<_Tp>::value; 86 template <typename _Tp> 87 constexpr bool is_rvalue_reference_v = is_rvalue_reference<_Tp>::value; 88 template <typename _Tp> 89 constexpr bool is_member_object_pointer_v = 90 is_member_object_pointer<_Tp>::value; 91 template <typename _Tp> 92 constexpr bool is_member_function_pointer_v = 93 is_member_function_pointer<_Tp>::value; 94 template <typename _Tp> 95 constexpr bool is_enum_v = is_enum<_Tp>::value; 96 template <typename _Tp> 97 constexpr bool is_union_v = is_union<_Tp>::value; 98 template <typename _Tp> 99 constexpr bool is_class_v = is_class<_Tp>::value; 100 template <typename _Tp> 101 constexpr bool is_function_v = is_function<_Tp>::value; 102 103 // See C++14 20.10.4.2, composite type categories 104 template <typename _Tp> 105 constexpr bool is_reference_v = is_reference<_Tp>::value; 106 template <typename _Tp> 107 constexpr bool is_arithmetic_v = is_arithmetic<_Tp>::value; 108 template <typename _Tp> 109 constexpr bool is_fundamental_v = is_fundamental<_Tp>::value; 110 template <typename _Tp> 111 constexpr bool is_object_v = is_object<_Tp>::value; 112 template <typename _Tp> 113 constexpr bool is_scalar_v = is_scalar<_Tp>::value; 114 template <typename _Tp> 115 constexpr bool is_compound_v = is_compound<_Tp>::value; 116 template <typename _Tp> 117 constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value; 118 119 // See C++14 20.10.4.3, type properties 120 template <typename _Tp> 121 constexpr bool is_const_v = is_const<_Tp>::value; 122 template <typename _Tp> 123 constexpr bool is_volatile_v = is_volatile<_Tp>::value; 124 #pragma GCC diagnostic push 125 #pragma GCC diagnostic ignored "-Wdeprecated-declarations" 126 template <typename _Tp> 127 constexpr bool is_trivial_v = is_trivial<_Tp>::value; 128 #pragma GCC diagnostic pop 129 template <typename _Tp> 130 constexpr bool is_trivially_copyable_v = is_trivially_copyable<_Tp>::value; 131 template <typename _Tp> 132 constexpr bool is_standard_layout_v = is_standard_layout<_Tp>::value; 133 #pragma GCC diagnostic push 134 #pragma GCC diagnostic ignored "-Wdeprecated-declarations" 135 template <typename _Tp> 136 constexpr bool is_pod_v = is_pod<_Tp>::value; 137 template <typename _Tp> 138 constexpr bool is_literal_type_v = is_literal_type<_Tp>::value; 139 #pragma GCC diagnostic pop 140 template <typename _Tp> 141 constexpr bool is_empty_v = is_empty<_Tp>::value; 142 template <typename _Tp> 143 constexpr bool is_polymorphic_v = is_polymorphic<_Tp>::value; 144 template <typename _Tp> 145 constexpr bool is_abstract_v = is_abstract<_Tp>::value; 146 template <typename _Tp> 147 constexpr bool is_final_v = is_final<_Tp>::value; 148 template <typename _Tp> 149 constexpr bool is_signed_v = is_signed<_Tp>::value; 150 template <typename _Tp> 151 constexpr bool is_unsigned_v = is_unsigned<_Tp>::value; 152 template <typename _Tp, typename... _Args> 153 constexpr bool is_constructible_v = is_constructible<_Tp, _Args...>::value; 154 template <typename _Tp> 155 constexpr bool is_default_constructible_v = 156 is_default_constructible<_Tp>::value; 157 template <typename _Tp> 158 constexpr bool is_copy_constructible_v = is_copy_constructible<_Tp>::value; 159 template <typename _Tp> 160 constexpr bool is_move_constructible_v = is_move_constructible<_Tp>::value; 161 template <typename _Tp, typename _Up> 162 constexpr bool is_assignable_v = is_assignable<_Tp, _Up>::value; 163 template <typename _Tp> 164 constexpr bool is_copy_assignable_v = is_copy_assignable<_Tp>::value; 165 template <typename _Tp> 166 constexpr bool is_move_assignable_v = is_move_assignable<_Tp>::value; 167 template <typename _Tp> 168 constexpr bool is_destructible_v = is_destructible<_Tp>::value; 169 template <typename _Tp, typename... _Args> 170 constexpr bool is_trivially_constructible_v = 171 is_trivially_constructible<_Tp, _Args...>::value; 172 template <typename _Tp> 173 constexpr bool is_trivially_default_constructible_v = 174 is_trivially_default_constructible<_Tp>::value; 175 template <typename _Tp> 176 constexpr bool is_trivially_copy_constructible_v = 177 is_trivially_copy_constructible<_Tp>::value; 178 template <typename _Tp> 179 constexpr bool is_trivially_move_constructible_v = 180 is_trivially_move_constructible<_Tp>::value; 181 template <typename _Tp, typename _Up> 182 constexpr bool is_trivially_assignable_v = 183 is_trivially_assignable<_Tp, _Up>::value; 184 template <typename _Tp> 185 constexpr bool is_trivially_copy_assignable_v = 186 is_trivially_copy_assignable<_Tp>::value; 187 template <typename _Tp> 188 constexpr bool is_trivially_move_assignable_v = 189 is_trivially_move_assignable<_Tp>::value; 190 template <typename _Tp> 191 constexpr bool is_trivially_destructible_v = 192 is_trivially_destructible<_Tp>::value; 193 template <typename _Tp, typename... _Args> 194 constexpr bool is_nothrow_constructible_v = 195 is_nothrow_constructible<_Tp, _Args...>::value; 196 template <typename _Tp> 197 constexpr bool is_nothrow_default_constructible_v = 198 is_nothrow_default_constructible<_Tp>::value; 199 template <typename _Tp> 200 constexpr bool is_nothrow_copy_constructible_v = 201 is_nothrow_copy_constructible<_Tp>::value; 202 template <typename _Tp> 203 constexpr bool is_nothrow_move_constructible_v = 204 is_nothrow_move_constructible<_Tp>::value; 205 template <typename _Tp, typename _Up> 206 constexpr bool is_nothrow_assignable_v = 207 is_nothrow_assignable<_Tp, _Up>::value; 208 template <typename _Tp> 209 constexpr bool is_nothrow_copy_assignable_v = 210 is_nothrow_copy_assignable<_Tp>::value; 211 template <typename _Tp> 212 constexpr bool is_nothrow_move_assignable_v = 213 is_nothrow_move_assignable<_Tp>::value; 214 template <typename _Tp> 215 constexpr bool is_nothrow_destructible_v = 216 is_nothrow_destructible<_Tp>::value; 217 template <typename _Tp> 218 constexpr bool has_virtual_destructor_v = 219 has_virtual_destructor<_Tp>::value; 220 221 // See C++14 20.10.5, type property queries 222 template <typename _Tp> 223 constexpr size_t alignment_of_v = alignment_of<_Tp>::value; 224 template <typename _Tp> 225 constexpr size_t rank_v = rank<_Tp>::value; 226 template <typename _Tp, unsigned _Idx = 0> 227 constexpr size_t extent_v = extent<_Tp, _Idx>::value; 228 229 // See C++14 20.10.6, type relations 230 template <typename _Tp, typename _Up> 231 constexpr bool is_same_v = false; 232 template <typename _Tp> 233 constexpr bool is_same_v<_Tp, _Tp> = true; 234 template <typename _Base, typename _Derived> 235 constexpr bool is_base_of_v = is_base_of<_Base, _Derived>::value; 236 template <typename _From, typename _To> 237 constexpr bool is_convertible_v = is_convertible<_From, _To>::value; 238 /// @} 239 240 // 3.3.2, Other type transformations 241 // invocation_type (still unimplemented) 242 // raw_invocation_type (still unimplemented) 243 // invocation_type_t (still unimplemented) 244 // raw_invocation_type_t (still unimplemented) 245 } // namespace fundamentals_v1 246 247 inline namespace fundamentals_v2 248 { 249 /** 250 * @defgroup lfts_detect Detection idiom 251 * @ingroup libfund-ts 252 * @since Library Fundamentals TS v2. C++14. 253 */ 254 /** @ingroup lfts_detect 255 * @{ 256 */ 257 #define __cpp_lib_experimental_detect 201505 258 259 // [meta.detect] 260 261 /// A metafunction that always yields void, used for detecting valid types. 262 template<typename...> using void_t = void; 263 264 #pragma GCC diagnostic push 265 #pragma GCC diagnostic ignored "-Wctor-dtor-privacy" 266 /// @internal 267 struct __nonesuchbase {}; 268 struct nonesuch : private __nonesuchbase 269 { 270 ~nonesuch() = delete; 271 nonesuch(nonesuch const&) = delete; 272 void operator=(nonesuch const&) = delete; 273 }; 274 #pragma GCC diagnostic pop 275 276 template<typename _Default, template<typename...> class _Op, typename... _Args> 277 using detected_or = std::__detected_or<_Default, _Op, _Args...>; 278 279 template<typename _Default, template<typename...> class _Op, typename... _Args> 280 using detected_or_t = typename detected_or<_Default, _Op, _Args...>::type; 281 282 template<template<typename...> class _Op, typename... _Args> 283 using detected_t = detected_or_t<nonesuch, _Op, _Args...>; 284 285 template<template<typename...> class _Op, typename... _Args> 286 using is_detected = typename detected_or<void, _Op, _Args...>::__is_detected; 287 288 template<template<typename...> class _Op, typename... _Args> 289 constexpr bool is_detected_v = is_detected<_Op, _Args...>::value; 290 291 template<typename _Expected, template<typename...> class _Op, typename... _Args> 292 using is_detected_exact = is_same<_Expected, detected_t<_Op, _Args...>>; 293 294 template<typename _Expected, template<typename...> class _Op, typename... _Args> 295 constexpr bool is_detected_exact_v 296 = is_detected_exact<_Expected, _Op, _Args...>::value; 297 298 template<typename _To, template<typename...> class _Op, typename... _Args> 299 using is_detected_convertible 300 = is_convertible<detected_t<_Op, _Args...>, _To>; 301 302 template<typename _To, template<typename...> class _Op, typename... _Args> 303 constexpr bool is_detected_convertible_v 304 = is_detected_convertible<_To, _Op, _Args...>::value; 305 /// @} 306 307 /** 308 * @defgroup lfts_logical Logical operator traits 309 * @ingroup libfund-ts 310 * @since Library Fundamentals TS v2. C++14. 311 */ 312 /** @ingroup lfts_logical 313 * @{ 314 */ 315 #define __cpp_lib_experimental_logical_traits 201511 316 317 template<typename... _Bn> 318 struct conjunction 319 : __and_<_Bn...> 320 { }; 321 322 template<typename... _Bn> 323 struct disjunction 324 : __or_<_Bn...> 325 { }; 326 327 template<typename _Pp> 328 struct negation 329 : __not_<_Pp> 330 { }; 331 332 template<typename... _Bn> 333 constexpr bool conjunction_v 334 = conjunction<_Bn...>::value; 335 336 template<typename... _Bn> 337 constexpr bool disjunction_v 338 = disjunction<_Bn...>::value; 339 340 template<typename _Pp> 341 constexpr bool negation_v 342 = negation<_Pp>::value; 343 /// @} 344 } // namespace fundamentals_v2 345 } // namespace experimental 346 347 _GLIBCXX_END_NAMESPACE_VERSION 348 } // namespace std 349 350 #endif // __cplusplus <= 201103L 351 352 #endif // _GLIBCXX_EXPERIMENTAL_TYPE_TRAITS
