libstdc++
ranges_util.h
Go to the documentation of this file.
1 // Utilities for representing and manipulating ranges -*- C++ -*-
2 
3 // Copyright (C) 2019-2021 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 bits/ranges_util.h
26  * This is an internal header file, included by other library headers.
27  * Do not attempt to use it directly. @headername{ranges}
28  */
29 
30 #ifndef _RANGES_UTIL_H
31 #define _RANGES_UTIL_H 1
32 
33 #if __cplusplus > 201703L
34 # include <bits/ranges_base.h>
35 
36 #ifdef __cpp_lib_ranges
37 namespace std _GLIBCXX_VISIBILITY(default)
38 {
39 _GLIBCXX_BEGIN_NAMESPACE_VERSION
40 namespace ranges
41 {
42  // C++20 24.5 [range.utility] Range utilities
43 
44  namespace __detail
45  {
46  template<typename _Range>
47  concept __simple_view = view<_Range> && range<const _Range>
48  && same_as<iterator_t<_Range>, iterator_t<const _Range>>
49  && same_as<sentinel_t<_Range>, sentinel_t<const _Range>>;
50 
51  template<typename _It>
52  concept __has_arrow = input_iterator<_It>
53  && (is_pointer_v<_It> || requires(_It __it) { __it.operator->(); });
54 
55  template<typename _Tp, typename _Up>
56  concept __not_same_as
57  = !same_as<remove_cvref_t<_Tp>, remove_cvref_t<_Up>>;
58  } // namespace __detail
59 
60  /// The ranges::view_interface class template
61  template<typename _Derived>
62  requires is_class_v<_Derived> && same_as<_Derived, remove_cv_t<_Derived>>
63  class view_interface : public view_base
64  {
65  private:
66  constexpr _Derived& _M_derived() noexcept
67  {
68  static_assert(derived_from<_Derived, view_interface<_Derived>>);
69  static_assert(view<_Derived>);
70  return static_cast<_Derived&>(*this);
71  }
72 
73  constexpr const _Derived& _M_derived() const noexcept
74  {
75  static_assert(derived_from<_Derived, view_interface<_Derived>>);
76  static_assert(view<_Derived>);
77  return static_cast<const _Derived&>(*this);
78  }
79 
80  public:
81  constexpr bool
82  empty() requires forward_range<_Derived>
83  { return ranges::begin(_M_derived()) == ranges::end(_M_derived()); }
84 
85  constexpr bool
86  empty() const requires forward_range<const _Derived>
87  { return ranges::begin(_M_derived()) == ranges::end(_M_derived()); }
88 
89  constexpr explicit
90  operator bool() requires requires { ranges::empty(_M_derived()); }
91  { return !ranges::empty(_M_derived()); }
92 
93  constexpr explicit
94  operator bool() const requires requires { ranges::empty(_M_derived()); }
95  { return !ranges::empty(_M_derived()); }
96 
97  constexpr auto
98  data() requires contiguous_iterator<iterator_t<_Derived>>
99  { return to_address(ranges::begin(_M_derived())); }
100 
101  constexpr auto
102  data() const
103  requires range<const _Derived>
104  && contiguous_iterator<iterator_t<const _Derived>>
105  { return to_address(ranges::begin(_M_derived())); }
106 
107  constexpr auto
108  size()
109  requires forward_range<_Derived>
110  && sized_sentinel_for<sentinel_t<_Derived>, iterator_t<_Derived>>
111  { return ranges::end(_M_derived()) - ranges::begin(_M_derived()); }
112 
113  constexpr auto
114  size() const
115  requires forward_range<const _Derived>
116  && sized_sentinel_for<sentinel_t<const _Derived>,
117  iterator_t<const _Derived>>
118  { return ranges::end(_M_derived()) - ranges::begin(_M_derived()); }
119 
120  constexpr decltype(auto)
121  front() requires forward_range<_Derived>
122  {
123  __glibcxx_assert(!empty());
124  return *ranges::begin(_M_derived());
125  }
126 
127  constexpr decltype(auto)
128  front() const requires forward_range<const _Derived>
129  {
130  __glibcxx_assert(!empty());
131  return *ranges::begin(_M_derived());
132  }
133 
134  constexpr decltype(auto)
135  back()
136  requires bidirectional_range<_Derived> && common_range<_Derived>
137  {
138  __glibcxx_assert(!empty());
139  return *ranges::prev(ranges::end(_M_derived()));
140  }
141 
142  constexpr decltype(auto)
143  back() const
144  requires bidirectional_range<const _Derived>
145  && common_range<const _Derived>
146  {
147  __glibcxx_assert(!empty());
148  return *ranges::prev(ranges::end(_M_derived()));
149  }
150 
151  template<random_access_range _Range = _Derived>
152  constexpr decltype(auto)
153  operator[](range_difference_t<_Range> __n)
154  { return ranges::begin(_M_derived())[__n]; }
155 
156  template<random_access_range _Range = const _Derived>
157  constexpr decltype(auto)
158  operator[](range_difference_t<_Range> __n) const
159  { return ranges::begin(_M_derived())[__n]; }
160  };
161 
162  namespace __detail
163  {
164  template<class _From, class _To>
165  concept __convertible_to_non_slicing = convertible_to<_From, _To>
166  && !(is_pointer_v<decay_t<_From>> && is_pointer_v<decay_t<_To>>
167  && __not_same_as<remove_pointer_t<decay_t<_From>>,
168  remove_pointer_t<decay_t<_To>>>);
169 
170  template<typename _Tp>
171  concept __pair_like
172  = !is_reference_v<_Tp> && requires(_Tp __t)
173  {
174  typename tuple_size<_Tp>::type;
175  requires derived_from<tuple_size<_Tp>, integral_constant<size_t, 2>>;
176  typename tuple_element_t<0, remove_const_t<_Tp>>;
177  typename tuple_element_t<1, remove_const_t<_Tp>>;
178  { get<0>(__t) } -> convertible_to<const tuple_element_t<0, _Tp>&>;
179  { get<1>(__t) } -> convertible_to<const tuple_element_t<1, _Tp>&>;
180  };
181 
182  template<typename _Tp, typename _Up, typename _Vp>
183  concept __pair_like_convertible_from
184  = !range<_Tp> && __pair_like<_Tp>
185  && constructible_from<_Tp, _Up, _Vp>
186  && __convertible_to_non_slicing<_Up, tuple_element_t<0, _Tp>>
187  && convertible_to<_Vp, tuple_element_t<1, _Tp>>;
188 
189  } // namespace __detail
190 
191  enum class subrange_kind : bool { unsized, sized };
192 
193  /// The ranges::subrange class template
194  template<input_or_output_iterator _It, sentinel_for<_It> _Sent = _It,
195  subrange_kind _Kind = sized_sentinel_for<_Sent, _It>
196  ? subrange_kind::sized : subrange_kind::unsized>
197  requires (_Kind == subrange_kind::sized || !sized_sentinel_for<_Sent, _It>)
198  class subrange : public view_interface<subrange<_It, _Sent, _Kind>>
199  {
200  private:
201  // XXX: gcc complains when using constexpr here
202  static const bool _S_store_size
203  = _Kind == subrange_kind::sized && !sized_sentinel_for<_Sent, _It>;
204 
205  _It _M_begin = _It();
206  [[no_unique_address]] _Sent _M_end = _Sent();
207 
208  using __size_type
209  = __detail::__make_unsigned_like_t<iter_difference_t<_It>>;
210 
211  template<typename, bool = _S_store_size>
212  struct _Size
213  { };
214 
215  template<typename _Tp>
216  struct _Size<_Tp, true>
217  { _Tp _M_size; };
218 
219  [[no_unique_address]] _Size<__size_type> _M_size = {};
220 
221  public:
222  subrange() = default;
223 
224  constexpr
225  subrange(__detail::__convertible_to_non_slicing<_It> auto __i, _Sent __s)
226  requires (!_S_store_size)
227  : _M_begin(std::move(__i)), _M_end(__s)
228  { }
229 
230  constexpr
231  subrange(__detail::__convertible_to_non_slicing<_It> auto __i, _Sent __s,
232  __size_type __n)
233  requires (_Kind == subrange_kind::sized)
234  : _M_begin(std::move(__i)), _M_end(__s)
235  {
236  if constexpr (_S_store_size)
237  _M_size._M_size = __n;
238  }
239 
240  template<__detail::__not_same_as<subrange> _Rng>
241  requires borrowed_range<_Rng>
242  && __detail::__convertible_to_non_slicing<iterator_t<_Rng>, _It>
243  && convertible_to<sentinel_t<_Rng>, _Sent>
244  constexpr
245  subrange(_Rng&& __r) requires _S_store_size && sized_range<_Rng>
246  : subrange(__r, ranges::size(__r))
247  { }
248 
249  template<__detail::__not_same_as<subrange> _Rng>
250  requires borrowed_range<_Rng>
251  && __detail::__convertible_to_non_slicing<iterator_t<_Rng>, _It>
252  && convertible_to<sentinel_t<_Rng>, _Sent>
253  constexpr
254  subrange(_Rng&& __r) requires (!_S_store_size)
255  : subrange(ranges::begin(__r), ranges::end(__r))
256  { }
257 
258  template<borrowed_range _Rng>
259  requires __detail::__convertible_to_non_slicing<iterator_t<_Rng>, _It>
260  && convertible_to<sentinel_t<_Rng>, _Sent>
261  constexpr
262  subrange(_Rng&& __r, __size_type __n)
263  requires (_Kind == subrange_kind::sized)
264  : subrange{ranges::begin(__r), ranges::end(__r), __n}
265  { }
266 
267  template<__detail::__not_same_as<subrange> _PairLike>
268  requires __detail::__pair_like_convertible_from<_PairLike, const _It&,
269  const _Sent&>
270  constexpr
271  operator _PairLike() const
272  { return _PairLike(_M_begin, _M_end); }
273 
274  constexpr _It
275  begin() const requires copyable<_It>
276  { return _M_begin; }
277 
278  [[nodiscard]] constexpr _It
279  begin() requires (!copyable<_It>)
280  { return std::move(_M_begin); }
281 
282  constexpr _Sent end() const { return _M_end; }
283 
284  constexpr bool empty() const { return _M_begin == _M_end; }
285 
286  constexpr __size_type
287  size() const requires (_Kind == subrange_kind::sized)
288  {
289  if constexpr (_S_store_size)
290  return _M_size._M_size;
291  else
292  return __detail::__to_unsigned_like(_M_end - _M_begin);
293  }
294 
295  [[nodiscard]] constexpr subrange
296  next(iter_difference_t<_It> __n = 1) const &
297  requires forward_iterator<_It>
298  {
299  auto __tmp = *this;
300  __tmp.advance(__n);
301  return __tmp;
302  }
303 
304  [[nodiscard]] constexpr subrange
305  next(iter_difference_t<_It> __n = 1) &&
306  {
307  advance(__n);
308  return std::move(*this);
309  }
310 
311  [[nodiscard]] constexpr subrange
312  prev(iter_difference_t<_It> __n = 1) const
313  requires bidirectional_iterator<_It>
314  {
315  auto __tmp = *this;
316  __tmp.advance(-__n);
317  return __tmp;
318  }
319 
320  constexpr subrange&
321  advance(iter_difference_t<_It> __n)
322  {
323  // _GLIBCXX_RESOLVE_LIB_DEFECTS
324  // 3433. subrange::advance(n) has UB when n < 0
325  if constexpr (bidirectional_iterator<_It>)
326  if (__n < 0)
327  {
328  ranges::advance(_M_begin, __n);
329  if constexpr (_S_store_size)
330  _M_size._M_size += __detail::__to_unsigned_like(-__n);
331  return *this;
332  }
333 
334  __glibcxx_assert(__n >= 0);
335  auto __d = __n - ranges::advance(_M_begin, __n, _M_end);
336  if constexpr (_S_store_size)
337  _M_size._M_size -= __detail::__to_unsigned_like(__d);
338  return *this;
339  }
340  };
341 
342  template<input_or_output_iterator _It, sentinel_for<_It> _Sent>
343  subrange(_It, _Sent) -> subrange<_It, _Sent>;
344 
345  template<input_or_output_iterator _It, sentinel_for<_It> _Sent>
346  subrange(_It, _Sent,
347  __detail::__make_unsigned_like_t<iter_difference_t<_It>>)
348  -> subrange<_It, _Sent, subrange_kind::sized>;
349 
350  template<borrowed_range _Rng>
351  subrange(_Rng&&)
352  -> subrange<iterator_t<_Rng>, sentinel_t<_Rng>,
353  (sized_range<_Rng>
354  || sized_sentinel_for<sentinel_t<_Rng>, iterator_t<_Rng>>)
355  ? subrange_kind::sized : subrange_kind::unsized>;
356 
357  template<borrowed_range _Rng>
358  subrange(_Rng&&,
359  __detail::__make_unsigned_like_t<range_difference_t<_Rng>>)
360  -> subrange<iterator_t<_Rng>, sentinel_t<_Rng>, subrange_kind::sized>;
361 
362  template<size_t _Num, class _It, class _Sent, subrange_kind _Kind>
363  requires (_Num < 2)
364  constexpr auto
365  get(const subrange<_It, _Sent, _Kind>& __r)
366  {
367  if constexpr (_Num == 0)
368  return __r.begin();
369  else
370  return __r.end();
371  }
372 
373  template<size_t _Num, class _It, class _Sent, subrange_kind _Kind>
374  requires (_Num < 2)
375  constexpr auto
376  get(subrange<_It, _Sent, _Kind>&& __r)
377  {
378  if constexpr (_Num == 0)
379  return __r.begin();
380  else
381  return __r.end();
382  }
383 
384  template<input_or_output_iterator _It, sentinel_for<_It> _Sent,
385  subrange_kind _Kind>
386  inline constexpr bool
387  enable_borrowed_range<subrange<_It, _Sent, _Kind>> = true;
388 
389  template<range _Range>
390  using borrowed_subrange_t = conditional_t<borrowed_range<_Range>,
391  subrange<iterator_t<_Range>>,
392  dangling>;
393 } // namespace ranges
394 
395 // The following ranges algorithms are used by <ranges>, and are defined here
396 // so that <ranges> can avoid including all of <bits/ranges_algo.h>.
397 namespace ranges
398 {
399  struct __find_fn
400  {
401  template<input_iterator _Iter, sentinel_for<_Iter> _Sent, typename _Tp,
402  typename _Proj = identity>
403  requires indirect_binary_predicate<ranges::equal_to,
404  projected<_Iter, _Proj>, const _Tp*>
405  constexpr _Iter
406  operator()(_Iter __first, _Sent __last,
407  const _Tp& __value, _Proj __proj = {}) const
408  {
409  while (__first != __last
410  && !(std::__invoke(__proj, *__first) == __value))
411  ++__first;
412  return __first;
413  }
414 
415  template<input_range _Range, typename _Tp, typename _Proj = identity>
416  requires indirect_binary_predicate<ranges::equal_to,
417  projected<iterator_t<_Range>, _Proj>,
418  const _Tp*>
419  constexpr borrowed_iterator_t<_Range>
420  operator()(_Range&& __r, const _Tp& __value, _Proj __proj = {}) const
421  {
422  return (*this)(ranges::begin(__r), ranges::end(__r),
423  __value, std::move(__proj));
424  }
425  };
426 
427  inline constexpr __find_fn find{};
428 
429  struct __find_if_fn
430  {
431  template<input_iterator _Iter, sentinel_for<_Iter> _Sent,
432  typename _Proj = identity,
433  indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
434  constexpr _Iter
435  operator()(_Iter __first, _Sent __last,
436  _Pred __pred, _Proj __proj = {}) const
437  {
438  while (__first != __last
439  && !(bool)std::__invoke(__pred, std::__invoke(__proj, *__first)))
440  ++__first;
441  return __first;
442  }
443 
444  template<input_range _Range, typename _Proj = identity,
445  indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>>
446  _Pred>
447  constexpr borrowed_iterator_t<_Range>
448  operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
449  {
450  return (*this)(ranges::begin(__r), ranges::end(__r),
451  std::move(__pred), std::move(__proj));
452  }
453  };
454 
455  inline constexpr __find_if_fn find_if{};
456 
457  struct __find_if_not_fn
458  {
459  template<input_iterator _Iter, sentinel_for<_Iter> _Sent,
460  typename _Proj = identity,
461  indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
462  constexpr _Iter
463  operator()(_Iter __first, _Sent __last,
464  _Pred __pred, _Proj __proj = {}) const
465  {
466  while (__first != __last
467  && (bool)std::__invoke(__pred, std::__invoke(__proj, *__first)))
468  ++__first;
469  return __first;
470  }
471 
472  template<input_range _Range, typename _Proj = identity,
473  indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>>
474  _Pred>
475  constexpr borrowed_iterator_t<_Range>
476  operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
477  {
478  return (*this)(ranges::begin(__r), ranges::end(__r),
479  std::move(__pred), std::move(__proj));
480  }
481  };
482 
483  inline constexpr __find_if_not_fn find_if_not{};
484 
485  template<typename _Iter1, typename _Iter2>
486  struct in_in_result
487  {
488  [[no_unique_address]] _Iter1 in1;
489  [[no_unique_address]] _Iter2 in2;
490 
491  template<typename _IIter1, typename _IIter2>
492  requires convertible_to<const _Iter1&, _IIter1>
493  && convertible_to<const _Iter2&, _IIter2>
494  constexpr
495  operator in_in_result<_IIter1, _IIter2>() const &
496  { return {in1, in2}; }
497 
498  template<typename _IIter1, typename _IIter2>
499  requires convertible_to<_Iter1, _IIter1>
500  && convertible_to<_Iter2, _IIter2>
501  constexpr
502  operator in_in_result<_IIter1, _IIter2>() &&
503  { return {std::move(in1), std::move(in2)}; }
504  };
505 
506  template<typename _Iter1, typename _Iter2>
507  using mismatch_result = in_in_result<_Iter1, _Iter2>;
508 
509  struct __mismatch_fn
510  {
511  template<input_iterator _Iter1, sentinel_for<_Iter1> _Sent1,
512  input_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
513  typename _Pred = ranges::equal_to,
514  typename _Proj1 = identity, typename _Proj2 = identity>
515  requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
516  constexpr mismatch_result<_Iter1, _Iter2>
517  operator()(_Iter1 __first1, _Sent1 __last1,
518  _Iter2 __first2, _Sent2 __last2, _Pred __pred = {},
519  _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
520  {
521  while (__first1 != __last1 && __first2 != __last2
522  && (bool)std::__invoke(__pred,
523  std::__invoke(__proj1, *__first1),
524  std::__invoke(__proj2, *__first2)))
525  {
526  ++__first1;
527  ++__first2;
528  }
529  return { std::move(__first1), std::move(__first2) };
530  }
531 
532  template<input_range _Range1, input_range _Range2,
533  typename _Pred = ranges::equal_to,
534  typename _Proj1 = identity, typename _Proj2 = identity>
535  requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>,
536  _Pred, _Proj1, _Proj2>
537  constexpr mismatch_result<iterator_t<_Range1>, iterator_t<_Range2>>
538  operator()(_Range1&& __r1, _Range2&& __r2, _Pred __pred = {},
539  _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
540  {
541  return (*this)(ranges::begin(__r1), ranges::end(__r1),
542  ranges::begin(__r2), ranges::end(__r2),
543  std::move(__pred),
544  std::move(__proj1), std::move(__proj2));
545  }
546  };
547 
548  inline constexpr __mismatch_fn mismatch{};
549 
550  struct __search_fn
551  {
552  template<forward_iterator _Iter1, sentinel_for<_Iter1> _Sent1,
553  forward_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
554  typename _Pred = ranges::equal_to,
555  typename _Proj1 = identity, typename _Proj2 = identity>
556  requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
557  constexpr subrange<_Iter1>
558  operator()(_Iter1 __first1, _Sent1 __last1,
559  _Iter2 __first2, _Sent2 __last2, _Pred __pred = {},
560  _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
561  {
562  if (__first1 == __last1 || __first2 == __last2)
563  return {__first1, __first1};
564 
565  for (;;)
566  {
567  for (;;)
568  {
569  if (__first1 == __last1)
570  return {__first1, __first1};
571  if (std::__invoke(__pred,
572  std::__invoke(__proj1, *__first1),
573  std::__invoke(__proj2, *__first2)))
574  break;
575  ++__first1;
576  }
577  auto __cur1 = __first1;
578  auto __cur2 = __first2;
579  for (;;)
580  {
581  if (++__cur2 == __last2)
582  return {__first1, ++__cur1};
583  if (++__cur1 == __last1)
584  return {__cur1, __cur1};
585  if (!(bool)std::__invoke(__pred,
586  std::__invoke(__proj1, *__cur1),
587  std::__invoke(__proj2, *__cur2)))
588  {
589  ++__first1;
590  break;
591  }
592  }
593  }
594  }
595 
596  template<forward_range _Range1, forward_range _Range2,
597  typename _Pred = ranges::equal_to,
598  typename _Proj1 = identity, typename _Proj2 = identity>
599  requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>,
600  _Pred, _Proj1, _Proj2>
601  constexpr borrowed_subrange_t<_Range1>
602  operator()(_Range1&& __r1, _Range2&& __r2, _Pred __pred = {},
603  _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
604  {
605  return (*this)(ranges::begin(__r1), ranges::end(__r1),
606  ranges::begin(__r2), ranges::end(__r2),
607  std::move(__pred),
608  std::move(__proj1), std::move(__proj2));
609  }
610  };
611 
612  inline constexpr __search_fn search{};
613 } // namespace ranges
614 
615  using ranges::get;
616 
617  template<typename _Iter, typename _Sent, ranges::subrange_kind _Kind>
618  struct tuple_size<ranges::subrange<_Iter, _Sent, _Kind>>
619  : integral_constant<size_t, 2>
620  { };
621 
622  template<typename _Iter, typename _Sent, ranges::subrange_kind _Kind>
623  struct tuple_element<0, ranges::subrange<_Iter, _Sent, _Kind>>
624  { using type = _Iter; };
625 
626  template<typename _Iter, typename _Sent, ranges::subrange_kind _Kind>
627  struct tuple_element<1, ranges::subrange<_Iter, _Sent, _Kind>>
628  { using type = _Sent; };
629 
630  template<typename _Iter, typename _Sent, ranges::subrange_kind _Kind>
631  struct tuple_element<0, const ranges::subrange<_Iter, _Sent, _Kind>>
632  { using type = _Iter; };
633 
634  template<typename _Iter, typename _Sent, ranges::subrange_kind _Kind>
635  struct tuple_element<1, const ranges::subrange<_Iter, _Sent, _Kind>>
636  { using type = _Sent; };
637 
638 _GLIBCXX_END_NAMESPACE_VERSION
639 } // namespace std
640 #endif // library concepts
641 #endif // C++20
642 #endif // _RANGES_UTIL_H
constexpr void advance(_InputIterator &__i, _Distance __n)
A generalization of pointer arithmetic.
Definition: simd.h:210
constexpr auto data(_Container &__cont) noexcept(noexcept(__cont.data())) -> decltype(__cont.data())
Return the data pointer of a container.
Definition: range_access.h:290
constexpr __invoke_result< _Callable, _Args... >::type __invoke(_Callable &&__fn, _Args &&... __args) noexcept(__is_nothrow_invocable< _Callable, _Args... >::value)
Invoke a callable object.
Definition: invoke.h:90
_Tp * end(valarray< _Tp > &__va) noexcept
Return an iterator pointing to one past the last element of the valarray.
Definition: valarray:1237
constexpr auto empty(const _Container &__cont) noexcept(noexcept(__cont.empty())) -> decltype(__cont.empty())
Return whether a container is empty.
Definition: range_access.h:263
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition: move.h:104
constexpr auto size(const _Container &__cont) noexcept(noexcept(__cont.size())) -> decltype(__cont.size())
Return the size of a container.
Definition: range_access.h:245
_Tp * begin(valarray< _Tp > &__va) noexcept
Return an iterator pointing to the first element of the valarray.
Definition: valarray:1215
typename conditional< _Cond, _Iftrue, _Iffalse >::type conditional_t
Alias template for conditional.
Definition: type_traits:2589
ISO C++ entities toplevel namespace is std.