1// <range_access.h> -*- C++ -*-
2
3// Copyright (C) 2010-2019 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>
37namespace 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]) noexcept
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]) noexcept
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]) noexcept
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]) noexcept
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) noexcept
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) noexcept
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