1 // <range_access.h> -*- C++ -*- 2 3 // Copyright (C) 2010-2018 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 bits/range_access.h 26 * This is an internal header file, included by other library headers. 27 * Do not attempt to use it directly. @headername{iterator} 28 */ 29 30 #ifndef _GLIBCXX_RANGE_ACCESS_H 31 #define _GLIBCXX_RANGE_ACCESS_H 1 32 33 #pragma GCC system_header 34 35 #if __cplusplus >= 201103L 36 #include <initializer_list> 37 namespace std _GLIBCXX_VISIBILITY(default) 38 { 39 _GLIBCXX_BEGIN_NAMESPACE_VERSION 40 41 /** 42 * @brief Return an iterator pointing to the first element of 43 * the container. 44 * @param __cont Container. 45 */ 46 template<typename _Container> 47 inline _GLIBCXX17_CONSTEXPR auto 48 begin(_Container& __cont) -> decltype(__cont.begin()) 49 { return __cont.begin(); } 50 51 /** 52 * @brief Return an iterator pointing to the first element of 53 * the const container. 54 * @param __cont Container. 55 */ 56 template<typename _Container> 57 inline _GLIBCXX17_CONSTEXPR auto 58 begin(const _Container& __cont) -> decltype(__cont.begin()) 59 { return __cont.begin(); } 60 61 /** 62 * @brief Return an iterator pointing to one past the last element of 63 * the container. 64 * @param __cont Container. 65 */ 66 template<typename _Container> 67 inline _GLIBCXX17_CONSTEXPR auto 68 end(_Container& __cont) -> decltype(__cont.end()) 69 { return __cont.end(); } 70 71 /** 72 * @brief Return an iterator pointing to one past the last element of 73 * the const container. 74 * @param __cont Container. 75 */ 76 template<typename _Container> 77 inline _GLIBCXX17_CONSTEXPR auto 78 end(const _Container& __cont) -> decltype(__cont.end()) 79 { return __cont.end(); } 80 81 /** 82 * @brief Return an iterator pointing to the first element of the array. 83 * @param __arr Array. 84 */ 85 template<typename _Tp, size_t _Nm> 86 inline _GLIBCXX14_CONSTEXPR _Tp* 87 begin(_Tp (&__arr)[_Nm]) 88 { return __arr; } 89 90 /** 91 * @brief Return an iterator pointing to one past the last element 92 * of the array. 93 * @param __arr Array. 94 */ 95 template<typename _Tp, size_t _Nm> 96 inline _GLIBCXX14_CONSTEXPR _Tp* 97 end(_Tp (&__arr)[_Nm]) 98 { return __arr + _Nm; } 99 100 #if __cplusplus >= 201402L 101 102 template<typename _Tp> class valarray; 103 // These overloads must be declared for cbegin and cend to use them. 104 template<typename _Tp> _Tp* begin(valarray<_Tp>&); 105 template<typename _Tp> const _Tp* begin(const valarray<_Tp>&); 106 template<typename _Tp> _Tp* end(valarray<_Tp>&); 107 template<typename _Tp> const _Tp* end(const valarray<_Tp>&); 108 109 /** 110 * @brief Return an iterator pointing to the first element of 111 * the const container. 112 * @param __cont Container. 113 */ 114 template<typename _Container> 115 inline constexpr auto 116 cbegin(const _Container& __cont) noexcept(noexcept(std::begin(__cont))) 117 -> decltype(std::begin(__cont)) 118 { return std::begin(__cont); } 119 120 /** 121 * @brief Return an iterator pointing to one past the last element of 122 * the const container. 123 * @param __cont Container. 124 */ 125 template<typename _Container> 126 inline constexpr auto 127 cend(const _Container& __cont) noexcept(noexcept(std::end(__cont))) 128 -> decltype(std::end(__cont)) 129 { return std::end(__cont); } 130 131 /** 132 * @brief Return a reverse iterator pointing to the last element of 133 * the container. 134 * @param __cont Container. 135 */ 136 template<typename _Container> 137 inline _GLIBCXX17_CONSTEXPR auto 138 rbegin(_Container& __cont) -> decltype(__cont.rbegin()) 139 { return __cont.rbegin(); } 140 141 /** 142 * @brief Return a reverse iterator pointing to the last element of 143 * the const container. 144 * @param __cont Container. 145 */ 146 template<typename _Container> 147 inline _GLIBCXX17_CONSTEXPR auto 148 rbegin(const _Container& __cont) -> decltype(__cont.rbegin()) 149 { return __cont.rbegin(); } 150 151 /** 152 * @brief Return a reverse iterator pointing one past the first element of 153 * the container. 154 * @param __cont Container. 155 */ 156 template<typename _Container> 157 inline _GLIBCXX17_CONSTEXPR auto 158 rend(_Container& __cont) -> decltype(__cont.rend()) 159 { return __cont.rend(); } 160 161 /** 162 * @brief Return a reverse iterator pointing one past the first element of 163 * the const container. 164 * @param __cont Container. 165 */ 166 template<typename _Container> 167 inline _GLIBCXX17_CONSTEXPR auto 168 rend(const _Container& __cont) -> decltype(__cont.rend()) 169 { return __cont.rend(); } 170 171 /** 172 * @brief Return a reverse iterator pointing to the last element of 173 * the array. 174 * @param __arr Array. 175 */ 176 template<typename _Tp, size_t _Nm> 177 inline _GLIBCXX17_CONSTEXPR reverse_iterator<_Tp*> 178 rbegin(_Tp (&__arr)[_Nm]) 179 { return reverse_iterator<_Tp*>(__arr + _Nm); } 180 181 /** 182 * @brief Return a reverse iterator pointing one past the first element of 183 * the array. 184 * @param __arr Array. 185 */ 186 template<typename _Tp, size_t _Nm> 187 inline _GLIBCXX17_CONSTEXPR reverse_iterator<_Tp*> 188 rend(_Tp (&__arr)[_Nm]) 189 { return reverse_iterator<_Tp*>(__arr); } 190 191 /** 192 * @brief Return a reverse iterator pointing to the last element of 193 * the initializer_list. 194 * @param __il initializer_list. 195 */ 196 template<typename _Tp> 197 inline _GLIBCXX17_CONSTEXPR reverse_iterator<const _Tp*> 198 rbegin(initializer_list<_Tp> __il) 199 { return reverse_iterator<const _Tp*>(__il.end()); } 200 201 /** 202 * @brief Return a reverse iterator pointing one past the first element of 203 * the initializer_list. 204 * @param __il initializer_list. 205 */ 206 template<typename _Tp> 207 inline _GLIBCXX17_CONSTEXPR reverse_iterator<const _Tp*> 208 rend(initializer_list<_Tp> __il) 209 { return reverse_iterator<const _Tp*>(__il.begin()); } 210 211 /** 212 * @brief Return a reverse iterator pointing to the last element of 213 * the const container. 214 * @param __cont Container. 215 */ 216 template<typename _Container> 217 inline _GLIBCXX17_CONSTEXPR auto 218 crbegin(const _Container& __cont) -> decltype(std::rbegin(__cont)) 219 { return std::rbegin(__cont); } 220 221 /** 222 * @brief Return a reverse iterator pointing one past the first element of 223 * the const container. 224 * @param __cont Container. 225 */ 226 template<typename _Container> 227 inline _GLIBCXX17_CONSTEXPR auto 228 crend(const _Container& __cont) -> decltype(std::rend(__cont)) 229 { return std::rend(__cont); } 230 231 #endif // C++14 232 233 #if __cplusplus >= 201703L 234 #define __cpp_lib_nonmember_container_access 201411 235 236 /** 237 * @brief Return the size of a container. 238 * @param __cont Container. 239 */ 240 template <typename _Container> 241 constexpr auto 242 size(const _Container& __cont) noexcept(noexcept(__cont.size())) 243 -> decltype(__cont.size()) 244 { return __cont.size(); } 245 246 /** 247 * @brief Return the size of an array. 248 * @param __array Array. 249 */ 250 template <typename _Tp, size_t _Nm> 251 constexpr size_t 252 size(const _Tp (&/*__array*/)[_Nm]) noexcept 253 { return _Nm; } 254 255 /** 256 * @brief Return whether a container is empty. 257 * @param __cont Container. 258 */ 259 template <typename _Container> 260 [[nodiscard]] constexpr auto 261 empty(const _Container& __cont) noexcept(noexcept(__cont.empty())) 262 -> decltype(__cont.empty()) 263 { return __cont.empty(); } 264 265 /** 266 * @brief Return whether an array is empty (always false). 267 * @param __array Container. 268 */ 269 template <typename _Tp, size_t _Nm> 270 [[nodiscard]] constexpr bool 271 empty(const _Tp (&/*__array*/)[_Nm]) noexcept 272 { return false; } 273 274 /** 275 * @brief Return whether an initializer_list is empty. 276 * @param __il Initializer list. 277 */ 278 template <typename _Tp> 279 [[nodiscard]] constexpr bool 280 empty(initializer_list<_Tp> __il) noexcept 281 { return __il.size() == 0;} 282 283 /** 284 * @brief Return the data pointer of a container. 285 * @param __cont Container. 286 */ 287 template <typename _Container> 288 constexpr auto 289 data(_Container& __cont) noexcept(noexcept(__cont.data())) 290 -> decltype(__cont.data()) 291 { return __cont.data(); } 292 293 /** 294 * @brief Return the data pointer of a const container. 295 * @param __cont Container. 296 */ 297 template <typename _Container> 298 constexpr auto 299 data(const _Container& __cont) noexcept(noexcept(__cont.data())) 300 -> decltype(__cont.data()) 301 { return __cont.data(); } 302 303 /** 304 * @brief Return the data pointer of an array. 305 * @param __array Array. 306 */ 307 template <typename _Tp, size_t _Nm> 308 constexpr _Tp* 309 data(_Tp (&__array)[_Nm]) noexcept 310 { return __array; } 311 312 /** 313 * @brief Return the data pointer of an initializer list. 314 * @param __il Initializer list. 315 */ 316 template <typename _Tp> 317 constexpr const _Tp* 318 data(initializer_list<_Tp> __il) noexcept 319 { return __il.begin(); } 320 321 #endif // C++17 322 323 _GLIBCXX_END_NAMESPACE_VERSION 324 } // namespace 325 326 #endif // C++11 327 328 #endif // _GLIBCXX_RANGE_ACCESS_H 329