libstdc++
range_access.h
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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*>
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*>
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
initializer_list
ISO C++ entities toplevel namespace is std.
constexpr const _Tp * end(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to one past the last element of the initializer_list.
_GLIBCXX17_CONSTEXPR auto crend(const _Container &__cont) -> decltype(std::rend(__cont))
Return a reverse iterator pointing one past the first element of the const container.
Definition: range_access.h:228
constexpr auto cbegin(const _Container &__cont) noexcept(noexcept(std::begin(__cont))) -> decltype(std::begin(__cont))
Return an iterator pointing to the first element of the const container.
Definition: range_access.h:116
constexpr auto cend(const _Container &__cont) noexcept(noexcept(std::end(__cont))) -> decltype(std::end(__cont))
Return an iterator pointing to one past the last element of the const container.
Definition: range_access.h:127
_GLIBCXX17_CONSTEXPR auto rbegin(_Container &__cont) -> decltype(__cont.rbegin())
Return a reverse iterator pointing to the last element of the container.
Definition: range_access.h:138
constexpr const _Tp * begin(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to the first element of the initializer_list.
_GLIBCXX17_CONSTEXPR auto crbegin(const _Container &__cont) -> decltype(std::rbegin(__cont))
Return a reverse iterator pointing to the last element of the const container.
Definition: range_access.h:218
_GLIBCXX17_CONSTEXPR auto rend(_Container &__cont) -> decltype(__cont.rend())
Return a reverse iterator pointing one past the first element of the container.
Definition: range_access.h:158