1 | // <ranges> -*- C++ -*- |
2 | |
3 | // Copyright (C) 2019-2024 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 include/ranges |
26 | * This is a Standard C++ Library header. |
27 | * @ingroup concepts |
28 | */ |
29 | |
30 | #ifndef _GLIBCXX_RANGES |
31 | #define _GLIBCXX_RANGES 1 |
32 | |
33 | #if __cplusplus > 201703L |
34 | |
35 | #pragma GCC system_header |
36 | |
37 | #include <concepts> |
38 | |
39 | #if __cpp_lib_concepts |
40 | |
41 | #include <compare> |
42 | #include <initializer_list> |
43 | #include <iterator> |
44 | #include <optional> |
45 | #include <span> |
46 | #include <string_view> |
47 | #include <tuple> |
48 | #if __cplusplus > 202002L |
49 | #include <variant> |
50 | #endif |
51 | #include <bits/ranges_util.h> |
52 | #include <bits/refwrap.h> |
53 | |
54 | #define __glibcxx_want_ranges |
55 | #define __glibcxx_want_ranges_as_const |
56 | #define __glibcxx_want_ranges_as_rvalue |
57 | #define __glibcxx_want_ranges_cartesian_product |
58 | #define __glibcxx_want_ranges_chunk |
59 | #define __glibcxx_want_ranges_chunk_by |
60 | #define __glibcxx_want_ranges_enumerate |
61 | #define __glibcxx_want_ranges_iota |
62 | #define __glibcxx_want_ranges_join_with |
63 | #define __glibcxx_want_ranges_repeat |
64 | #define __glibcxx_want_ranges_slide |
65 | #define __glibcxx_want_ranges_stride |
66 | #define __glibcxx_want_ranges_to_container |
67 | #define __glibcxx_want_ranges_zip |
68 | #include <bits/version.h> |
69 | |
70 | #ifdef __glibcxx_generator // C++ >= 23 && __glibcxx_coroutine |
71 | # include <bits/elements_of.h> |
72 | #endif |
73 | |
74 | /** |
75 | * @defgroup ranges Ranges |
76 | * |
77 | * Components for dealing with ranges of elements. |
78 | */ |
79 | |
80 | namespace std _GLIBCXX_VISIBILITY(default) |
81 | { |
82 | _GLIBCXX_BEGIN_NAMESPACE_VERSION |
83 | namespace ranges |
84 | { |
85 | // [range.access] customization point objects |
86 | // [range.req] range and view concepts |
87 | // [range.dangling] dangling iterator handling |
88 | // Defined in <bits/ranges_base.h> |
89 | |
90 | // [view.interface] View interface |
91 | // [range.subrange] Sub-ranges |
92 | // Defined in <bits/ranges_util.h> |
93 | |
94 | // C++20 24.6 [range.factories] Range factories |
95 | |
96 | /// A view that contains no elements. |
97 | template<typename _Tp> requires is_object_v<_Tp> |
98 | class empty_view |
99 | : public view_interface<empty_view<_Tp>> |
100 | { |
101 | public: |
102 | static constexpr _Tp* begin() noexcept { return nullptr; } |
103 | static constexpr _Tp* end() noexcept { return nullptr; } |
104 | static constexpr _Tp* data() noexcept { return nullptr; } |
105 | static constexpr size_t size() noexcept { return 0; } |
106 | static constexpr bool empty() noexcept { return true; } |
107 | }; |
108 | |
109 | template<typename _Tp> |
110 | inline constexpr bool enable_borrowed_range<empty_view<_Tp>> = true; |
111 | |
112 | namespace __detail |
113 | { |
114 | #if __cpp_lib_ranges >= 202207L // C++ >= 23 |
115 | // P2494R2 Relaxing range adaptors to allow for move only types |
116 | template<typename _Tp> |
117 | concept __boxable = move_constructible<_Tp> && is_object_v<_Tp>; |
118 | #else |
119 | template<typename _Tp> |
120 | concept __boxable = copy_constructible<_Tp> && is_object_v<_Tp>; |
121 | #endif |
122 | |
123 | template<__boxable _Tp> |
124 | struct __box : std::optional<_Tp> |
125 | { |
126 | using std::optional<_Tp>::optional; |
127 | |
128 | constexpr |
129 | __box() |
130 | noexcept(is_nothrow_default_constructible_v<_Tp>) |
131 | requires default_initializable<_Tp> |
132 | : std::optional<_Tp>{std::in_place} |
133 | { } |
134 | |
135 | __box(const __box&) = default; |
136 | __box(__box&&) = default; |
137 | |
138 | using std::optional<_Tp>::operator=; |
139 | |
140 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
141 | // 3477. Simplify constraints for semiregular-box |
142 | // 3572. copyable-box should be fully constexpr |
143 | constexpr __box& |
144 | operator=(const __box& __that) |
145 | noexcept(is_nothrow_copy_constructible_v<_Tp>) |
146 | requires (!copyable<_Tp>) && copy_constructible<_Tp> |
147 | { |
148 | if (this != std::__addressof(__that)) |
149 | { |
150 | if ((bool)__that) |
151 | this->emplace(*__that); |
152 | else |
153 | this->reset(); |
154 | } |
155 | return *this; |
156 | } |
157 | |
158 | constexpr __box& |
159 | operator=(__box&& __that) |
160 | noexcept(is_nothrow_move_constructible_v<_Tp>) |
161 | requires (!movable<_Tp>) |
162 | { |
163 | if (this != std::__addressof(__that)) |
164 | { |
165 | if ((bool)__that) |
166 | this->emplace(std::move(*__that)); |
167 | else |
168 | this->reset(); |
169 | } |
170 | return *this; |
171 | } |
172 | }; |
173 | |
174 | template<typename _Tp> |
175 | concept __boxable_copyable |
176 | = copy_constructible<_Tp> |
177 | && (copyable<_Tp> || (is_nothrow_move_constructible_v<_Tp> |
178 | && is_nothrow_copy_constructible_v<_Tp>)); |
179 | template<typename _Tp> |
180 | concept __boxable_movable |
181 | = (!copy_constructible<_Tp>) |
182 | && (movable<_Tp> || is_nothrow_move_constructible_v<_Tp>); |
183 | |
184 | // For types which are already copyable (or since C++23, movable) |
185 | // this specialization of the box wrapper stores the object directly |
186 | // without going through std::optional. It provides just the subset of |
187 | // the primary template's API that we currently use. |
188 | template<__boxable _Tp> |
189 | requires __boxable_copyable<_Tp> || __boxable_movable<_Tp> |
190 | struct __box<_Tp> |
191 | { |
192 | private: |
193 | [[no_unique_address]] _Tp _M_value = _Tp(); |
194 | |
195 | public: |
196 | __box() requires default_initializable<_Tp> = default; |
197 | |
198 | constexpr explicit |
199 | __box(const _Tp& __t) |
200 | noexcept(is_nothrow_copy_constructible_v<_Tp>) |
201 | requires copy_constructible<_Tp> |
202 | : _M_value(__t) |
203 | { } |
204 | |
205 | constexpr explicit |
206 | __box(_Tp&& __t) |
207 | noexcept(is_nothrow_move_constructible_v<_Tp>) |
208 | : _M_value(std::move(__t)) |
209 | { } |
210 | |
211 | template<typename... _Args> |
212 | requires constructible_from<_Tp, _Args...> |
213 | constexpr explicit |
214 | __box(in_place_t, _Args&&... __args) |
215 | noexcept(is_nothrow_constructible_v<_Tp, _Args...>) |
216 | : _M_value(std::forward<_Args>(__args)...) |
217 | { } |
218 | |
219 | __box(const __box&) = default; |
220 | __box(__box&&) = default; |
221 | __box& operator=(const __box&) requires copyable<_Tp> = default; |
222 | __box& operator=(__box&&) requires movable<_Tp> = default; |
223 | |
224 | // When _Tp is nothrow_copy_constructible but not copy_assignable, |
225 | // copy assignment is implemented via destroy-then-copy-construct. |
226 | constexpr __box& |
227 | operator=(const __box& __that) noexcept |
228 | requires (!copyable<_Tp>) && copy_constructible<_Tp> |
229 | { |
230 | static_assert(is_nothrow_copy_constructible_v<_Tp>); |
231 | if (this != std::__addressof(__that)) |
232 | { |
233 | _M_value.~_Tp(); |
234 | std::construct_at(std::__addressof(_M_value), *__that); |
235 | } |
236 | return *this; |
237 | } |
238 | |
239 | // Likewise for move assignment. |
240 | constexpr __box& |
241 | operator=(__box&& __that) noexcept |
242 | requires (!movable<_Tp>) |
243 | { |
244 | static_assert(is_nothrow_move_constructible_v<_Tp>); |
245 | if (this != std::__addressof(__that)) |
246 | { |
247 | _M_value.~_Tp(); |
248 | std::construct_at(std::__addressof(_M_value), std::move(*__that)); |
249 | } |
250 | return *this; |
251 | } |
252 | |
253 | constexpr bool |
254 | has_value() const noexcept |
255 | { return true; }; |
256 | |
257 | constexpr _Tp& |
258 | operator*() & noexcept |
259 | { return _M_value; } |
260 | |
261 | constexpr const _Tp& |
262 | operator*() const & noexcept |
263 | { return _M_value; } |
264 | |
265 | constexpr _Tp&& |
266 | operator*() && noexcept |
267 | { return std::move(_M_value); } |
268 | |
269 | constexpr const _Tp&& |
270 | operator*() const && noexcept |
271 | { return std::move(_M_value); } |
272 | |
273 | constexpr _Tp* |
274 | operator->() noexcept |
275 | { return std::__addressof(_M_value); } |
276 | |
277 | constexpr const _Tp* |
278 | operator->() const noexcept |
279 | { return std::__addressof(_M_value); } |
280 | }; |
281 | } // namespace __detail |
282 | |
283 | /// A view that contains exactly one element. |
284 | #if __cpp_lib_ranges >= 202207L // C++ >= 23 |
285 | template<move_constructible _Tp> |
286 | #else |
287 | template<copy_constructible _Tp> |
288 | #endif |
289 | requires is_object_v<_Tp> |
290 | class single_view : public view_interface<single_view<_Tp>> |
291 | { |
292 | public: |
293 | single_view() requires default_initializable<_Tp> = default; |
294 | |
295 | constexpr explicit |
296 | single_view(const _Tp& __t) |
297 | noexcept(is_nothrow_copy_constructible_v<_Tp>) |
298 | requires copy_constructible<_Tp> |
299 | : _M_value(__t) |
300 | { } |
301 | |
302 | constexpr explicit |
303 | single_view(_Tp&& __t) |
304 | noexcept(is_nothrow_move_constructible_v<_Tp>) |
305 | : _M_value(std::move(__t)) |
306 | { } |
307 | |
308 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
309 | // 3428. single_view's in place constructor should be explicit |
310 | template<typename... _Args> |
311 | requires constructible_from<_Tp, _Args...> |
312 | constexpr explicit |
313 | single_view(in_place_t, _Args&&... __args) |
314 | noexcept(is_nothrow_constructible_v<_Tp, _Args...>) |
315 | : _M_value{in_place, std::forward<_Args>(__args)...} |
316 | { } |
317 | |
318 | constexpr _Tp* |
319 | begin() noexcept |
320 | { return data(); } |
321 | |
322 | constexpr const _Tp* |
323 | begin() const noexcept |
324 | { return data(); } |
325 | |
326 | constexpr _Tp* |
327 | end() noexcept |
328 | { return data() + 1; } |
329 | |
330 | constexpr const _Tp* |
331 | end() const noexcept |
332 | { return data() + 1; } |
333 | |
334 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
335 | // 4035. single_view should provide empty |
336 | static constexpr bool |
337 | empty() noexcept |
338 | { return false; } |
339 | |
340 | static constexpr size_t |
341 | size() noexcept |
342 | { return 1; } |
343 | |
344 | constexpr _Tp* |
345 | data() noexcept |
346 | { return _M_value.operator->(); } |
347 | |
348 | constexpr const _Tp* |
349 | data() const noexcept |
350 | { return _M_value.operator->(); } |
351 | |
352 | private: |
353 | [[no_unique_address]] __detail::__box<_Tp> _M_value; |
354 | }; |
355 | |
356 | template<typename _Tp> |
357 | single_view(_Tp) -> single_view<_Tp>; |
358 | |
359 | namespace __detail |
360 | { |
361 | template<typename _Wp> |
362 | constexpr auto __to_signed_like(_Wp __w) noexcept |
363 | { |
364 | if constexpr (!integral<_Wp>) |
365 | return iter_difference_t<_Wp>(); |
366 | else if constexpr (sizeof(iter_difference_t<_Wp>) > sizeof(_Wp)) |
367 | return iter_difference_t<_Wp>(__w); |
368 | else if constexpr (sizeof(ptrdiff_t) > sizeof(_Wp)) |
369 | return ptrdiff_t(__w); |
370 | else if constexpr (sizeof(long long) > sizeof(_Wp)) |
371 | return (long long)(__w); |
372 | #ifdef __SIZEOF_INT128__ |
373 | else if constexpr (__SIZEOF_INT128__ > sizeof(_Wp)) |
374 | return __int128(__w); |
375 | #endif |
376 | else |
377 | return __max_diff_type(__w); |
378 | } |
379 | |
380 | template<typename _Wp> |
381 | using __iota_diff_t = decltype(__to_signed_like(std::declval<_Wp>())); |
382 | |
383 | template<typename _It> |
384 | concept __decrementable = incrementable<_It> |
385 | && requires(_It __i) |
386 | { |
387 | { --__i } -> same_as<_It&>; |
388 | { __i-- } -> same_as<_It>; |
389 | }; |
390 | |
391 | template<typename _It> |
392 | concept __advanceable = __decrementable<_It> && totally_ordered<_It> |
393 | && requires( _It __i, const _It __j, const __iota_diff_t<_It> __n) |
394 | { |
395 | { __i += __n } -> same_as<_It&>; |
396 | { __i -= __n } -> same_as<_It&>; |
397 | _It(__j + __n); |
398 | _It(__n + __j); |
399 | _It(__j - __n); |
400 | { __j - __j } -> convertible_to<__iota_diff_t<_It>>; |
401 | }; |
402 | |
403 | template<typename _Winc> |
404 | struct __iota_view_iter_cat |
405 | { }; |
406 | |
407 | template<incrementable _Winc> |
408 | struct __iota_view_iter_cat<_Winc> |
409 | { using iterator_category = input_iterator_tag; }; |
410 | } // namespace __detail |
411 | |
412 | template<weakly_incrementable _Winc, |
413 | semiregular _Bound = unreachable_sentinel_t> |
414 | requires std::__detail::__weakly_eq_cmp_with<_Winc, _Bound> |
415 | && copyable<_Winc> |
416 | class iota_view : public view_interface<iota_view<_Winc, _Bound>> |
417 | { |
418 | private: |
419 | struct _Sentinel; |
420 | |
421 | struct _Iterator : __detail::__iota_view_iter_cat<_Winc> |
422 | { |
423 | private: |
424 | static auto |
425 | _S_iter_concept() |
426 | { |
427 | using namespace __detail; |
428 | if constexpr (__advanceable<_Winc>) |
429 | return random_access_iterator_tag{}; |
430 | else if constexpr (__decrementable<_Winc>) |
431 | return bidirectional_iterator_tag{}; |
432 | else if constexpr (incrementable<_Winc>) |
433 | return forward_iterator_tag{}; |
434 | else |
435 | return input_iterator_tag{}; |
436 | } |
437 | |
438 | public: |
439 | using iterator_concept = decltype(_S_iter_concept()); |
440 | // iterator_category defined in __iota_view_iter_cat |
441 | using value_type = _Winc; |
442 | using difference_type = __detail::__iota_diff_t<_Winc>; |
443 | |
444 | _Iterator() requires default_initializable<_Winc> = default; |
445 | |
446 | constexpr explicit |
447 | _Iterator(_Winc __value) |
448 | : _M_value(__value) { } |
449 | |
450 | constexpr _Winc |
451 | operator*() const noexcept(is_nothrow_copy_constructible_v<_Winc>) |
452 | { return _M_value; } |
453 | |
454 | constexpr _Iterator& |
455 | operator++() |
456 | { |
457 | ++_M_value; |
458 | return *this; |
459 | } |
460 | |
461 | constexpr void |
462 | operator++(int) |
463 | { ++*this; } |
464 | |
465 | constexpr _Iterator |
466 | operator++(int) requires incrementable<_Winc> |
467 | { |
468 | auto __tmp = *this; |
469 | ++*this; |
470 | return __tmp; |
471 | } |
472 | |
473 | constexpr _Iterator& |
474 | operator--() requires __detail::__decrementable<_Winc> |
475 | { |
476 | --_M_value; |
477 | return *this; |
478 | } |
479 | |
480 | constexpr _Iterator |
481 | operator--(int) requires __detail::__decrementable<_Winc> |
482 | { |
483 | auto __tmp = *this; |
484 | --*this; |
485 | return __tmp; |
486 | } |
487 | |
488 | constexpr _Iterator& |
489 | operator+=(difference_type __n) requires __detail::__advanceable<_Winc> |
490 | { |
491 | using __detail::__is_integer_like; |
492 | using __detail::__is_signed_integer_like; |
493 | if constexpr (__is_integer_like<_Winc> |
494 | && !__is_signed_integer_like<_Winc>) |
495 | { |
496 | if (__n >= difference_type(0)) |
497 | _M_value += static_cast<_Winc>(__n); |
498 | else |
499 | _M_value -= static_cast<_Winc>(-__n); |
500 | } |
501 | else |
502 | _M_value += __n; |
503 | return *this; |
504 | } |
505 | |
506 | constexpr _Iterator& |
507 | operator-=(difference_type __n) requires __detail::__advanceable<_Winc> |
508 | { |
509 | using __detail::__is_integer_like; |
510 | using __detail::__is_signed_integer_like; |
511 | if constexpr (__is_integer_like<_Winc> |
512 | && !__is_signed_integer_like<_Winc>) |
513 | { |
514 | if (__n >= difference_type(0)) |
515 | _M_value -= static_cast<_Winc>(__n); |
516 | else |
517 | _M_value += static_cast<_Winc>(-__n); |
518 | } |
519 | else |
520 | _M_value -= __n; |
521 | return *this; |
522 | } |
523 | |
524 | constexpr _Winc |
525 | operator[](difference_type __n) const |
526 | requires __detail::__advanceable<_Winc> |
527 | { return _Winc(_M_value + __n); } |
528 | |
529 | friend constexpr bool |
530 | operator==(const _Iterator& __x, const _Iterator& __y) |
531 | requires equality_comparable<_Winc> |
532 | { return __x._M_value == __y._M_value; } |
533 | |
534 | friend constexpr bool |
535 | operator<(const _Iterator& __x, const _Iterator& __y) |
536 | requires totally_ordered<_Winc> |
537 | { return __x._M_value < __y._M_value; } |
538 | |
539 | friend constexpr bool |
540 | operator>(const _Iterator& __x, const _Iterator& __y) |
541 | requires totally_ordered<_Winc> |
542 | { return __y < __x; } |
543 | |
544 | friend constexpr bool |
545 | operator<=(const _Iterator& __x, const _Iterator& __y) |
546 | requires totally_ordered<_Winc> |
547 | { return !(__y < __x); } |
548 | |
549 | friend constexpr bool |
550 | operator>=(const _Iterator& __x, const _Iterator& __y) |
551 | requires totally_ordered<_Winc> |
552 | { return !(__x < __y); } |
553 | |
554 | #ifdef __cpp_lib_three_way_comparison |
555 | friend constexpr auto |
556 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
557 | requires totally_ordered<_Winc> && three_way_comparable<_Winc> |
558 | { return __x._M_value <=> __y._M_value; } |
559 | #endif |
560 | |
561 | friend constexpr _Iterator |
562 | operator+(_Iterator __i, difference_type __n) |
563 | requires __detail::__advanceable<_Winc> |
564 | { |
565 | __i += __n; |
566 | return __i; |
567 | } |
568 | |
569 | friend constexpr _Iterator |
570 | operator+(difference_type __n, _Iterator __i) |
571 | requires __detail::__advanceable<_Winc> |
572 | { return __i += __n; } |
573 | |
574 | friend constexpr _Iterator |
575 | operator-(_Iterator __i, difference_type __n) |
576 | requires __detail::__advanceable<_Winc> |
577 | { |
578 | __i -= __n; |
579 | return __i; |
580 | } |
581 | |
582 | friend constexpr difference_type |
583 | operator-(const _Iterator& __x, const _Iterator& __y) |
584 | requires __detail::__advanceable<_Winc> |
585 | { |
586 | using __detail::__is_integer_like; |
587 | using __detail::__is_signed_integer_like; |
588 | using _Dt = difference_type; |
589 | if constexpr (__is_integer_like<_Winc>) |
590 | { |
591 | if constexpr (__is_signed_integer_like<_Winc>) |
592 | return _Dt(_Dt(__x._M_value) - _Dt(__y._M_value)); |
593 | else |
594 | return (__y._M_value > __x._M_value) |
595 | ? _Dt(-_Dt(__y._M_value - __x._M_value)) |
596 | : _Dt(__x._M_value - __y._M_value); |
597 | } |
598 | else |
599 | return __x._M_value - __y._M_value; |
600 | } |
601 | |
602 | private: |
603 | _Winc _M_value = _Winc(); |
604 | |
605 | friend iota_view; |
606 | friend _Sentinel; |
607 | }; |
608 | |
609 | struct _Sentinel |
610 | { |
611 | private: |
612 | constexpr bool |
613 | _M_equal(const _Iterator& __x) const |
614 | { return __x._M_value == _M_bound; } |
615 | |
616 | constexpr auto |
617 | _M_distance_from(const _Iterator& __x) const |
618 | { return _M_bound - __x._M_value; } |
619 | |
620 | _Bound _M_bound = _Bound(); |
621 | |
622 | public: |
623 | _Sentinel() = default; |
624 | |
625 | constexpr explicit |
626 | _Sentinel(_Bound __bound) |
627 | : _M_bound(__bound) { } |
628 | |
629 | friend constexpr bool |
630 | operator==(const _Iterator& __x, const _Sentinel& __y) |
631 | { return __y._M_equal(__x); } |
632 | |
633 | friend constexpr iter_difference_t<_Winc> |
634 | operator-(const _Iterator& __x, const _Sentinel& __y) |
635 | requires sized_sentinel_for<_Bound, _Winc> |
636 | { return -__y._M_distance_from(__x); } |
637 | |
638 | friend constexpr iter_difference_t<_Winc> |
639 | operator-(const _Sentinel& __x, const _Iterator& __y) |
640 | requires sized_sentinel_for<_Bound, _Winc> |
641 | { return __x._M_distance_from(__y); } |
642 | |
643 | friend iota_view; |
644 | }; |
645 | |
646 | _Winc _M_value = _Winc(); |
647 | [[no_unique_address]] _Bound _M_bound = _Bound(); |
648 | |
649 | public: |
650 | iota_view() requires default_initializable<_Winc> = default; |
651 | |
652 | constexpr explicit |
653 | iota_view(_Winc __value) |
654 | : _M_value(__value) |
655 | { } |
656 | |
657 | constexpr |
658 | iota_view(type_identity_t<_Winc> __value, |
659 | type_identity_t<_Bound> __bound) |
660 | : _M_value(__value), _M_bound(__bound) |
661 | { |
662 | if constexpr (totally_ordered_with<_Winc, _Bound>) |
663 | __glibcxx_assert( bool(__value <= __bound) ); |
664 | } |
665 | |
666 | constexpr |
667 | iota_view(_Iterator __first, _Iterator __last) |
668 | requires same_as<_Winc, _Bound> |
669 | : iota_view(__first._M_value, __last._M_value) |
670 | { } |
671 | |
672 | constexpr |
673 | iota_view(_Iterator __first, unreachable_sentinel_t __last) |
674 | requires same_as<_Bound, unreachable_sentinel_t> |
675 | : iota_view(__first._M_value, __last) |
676 | { } |
677 | |
678 | constexpr |
679 | iota_view(_Iterator __first, _Sentinel __last) |
680 | requires (!same_as<_Winc, _Bound>) && (!same_as<_Bound, unreachable_sentinel_t>) |
681 | : iota_view(__first._M_value, __last._M_bound) |
682 | { } |
683 | |
684 | constexpr _Iterator |
685 | begin() const { return _Iterator{_M_value}; } |
686 | |
687 | constexpr auto |
688 | end() const |
689 | { |
690 | if constexpr (same_as<_Bound, unreachable_sentinel_t>) |
691 | return unreachable_sentinel; |
692 | else |
693 | return _Sentinel{_M_bound}; |
694 | } |
695 | |
696 | constexpr _Iterator |
697 | end() const requires same_as<_Winc, _Bound> |
698 | { return _Iterator{_M_bound}; } |
699 | |
700 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
701 | // 4001. iota_view should provide empty |
702 | constexpr bool |
703 | empty() const |
704 | { return _M_value == _M_bound; } |
705 | |
706 | constexpr auto |
707 | size() const |
708 | requires (same_as<_Winc, _Bound> && __detail::__advanceable<_Winc>) |
709 | || (integral<_Winc> && integral<_Bound>) |
710 | || sized_sentinel_for<_Bound, _Winc> |
711 | { |
712 | using __detail::__is_integer_like; |
713 | using __detail::__to_unsigned_like; |
714 | if constexpr (integral<_Winc> && integral<_Bound>) |
715 | { |
716 | using _Up = make_unsigned_t<decltype(_M_bound - _M_value)>; |
717 | return _Up(_M_bound) - _Up(_M_value); |
718 | } |
719 | else if constexpr (__is_integer_like<_Winc>) |
720 | return __to_unsigned_like(_M_bound) - __to_unsigned_like(_M_value); |
721 | else |
722 | return __to_unsigned_like(_M_bound - _M_value); |
723 | } |
724 | }; |
725 | |
726 | template<typename _Winc, typename _Bound> |
727 | requires (!__detail::__is_integer_like<_Winc> |
728 | || !__detail::__is_integer_like<_Bound> |
729 | || (__detail::__is_signed_integer_like<_Winc> |
730 | == __detail::__is_signed_integer_like<_Bound>)) |
731 | iota_view(_Winc, _Bound) -> iota_view<_Winc, _Bound>; |
732 | |
733 | template<typename _Winc, typename _Bound> |
734 | inline constexpr bool |
735 | enable_borrowed_range<iota_view<_Winc, _Bound>> = true; |
736 | |
737 | namespace views |
738 | { |
739 | template<typename _Tp> |
740 | inline constexpr empty_view<_Tp> empty{}; |
741 | |
742 | namespace __detail |
743 | { |
744 | template<typename _Tp> |
745 | concept __can_single_view |
746 | = requires { single_view<decay_t<_Tp>>(std::declval<_Tp>()); }; |
747 | } // namespace __detail |
748 | |
749 | struct _Single |
750 | { |
751 | template<__detail::__can_single_view _Tp> |
752 | constexpr auto |
753 | operator() [[nodiscard]] (_Tp&& __e) const |
754 | noexcept(noexcept(single_view<decay_t<_Tp>>(std::forward<_Tp>(__e)))) |
755 | { return single_view<decay_t<_Tp>>(std::forward<_Tp>(__e)); } |
756 | }; |
757 | |
758 | inline constexpr _Single single{}; |
759 | |
760 | namespace __detail |
761 | { |
762 | template<typename... _Args> |
763 | concept __can_iota_view = requires { iota_view(std::declval<_Args>()...); }; |
764 | } // namespace __detail |
765 | |
766 | struct _Iota |
767 | { |
768 | template<__detail::__can_iota_view _Tp> |
769 | constexpr auto |
770 | operator() [[nodiscard]] (_Tp&& __e) const |
771 | { return iota_view(std::forward<_Tp>(__e)); } |
772 | |
773 | template<typename _Tp, typename _Up> |
774 | requires __detail::__can_iota_view<_Tp, _Up> |
775 | constexpr auto |
776 | operator() [[nodiscard]] (_Tp&& __e, _Up&& __f) const |
777 | { return iota_view(std::forward<_Tp>(__e), std::forward<_Up>(__f)); } |
778 | }; |
779 | |
780 | inline constexpr _Iota iota{}; |
781 | } // namespace views |
782 | |
783 | #if _GLIBCXX_HOSTED |
784 | namespace __detail |
785 | { |
786 | template<typename _Val, typename _CharT, typename _Traits> |
787 | concept __stream_extractable |
788 | = requires(basic_istream<_CharT, _Traits>& is, _Val& t) { is >> t; }; |
789 | } // namespace __detail |
790 | |
791 | template<movable _Val, typename _CharT, |
792 | typename _Traits = char_traits<_CharT>> |
793 | requires default_initializable<_Val> |
794 | && __detail::__stream_extractable<_Val, _CharT, _Traits> |
795 | class basic_istream_view |
796 | : public view_interface<basic_istream_view<_Val, _CharT, _Traits>> |
797 | { |
798 | public: |
799 | constexpr explicit |
800 | basic_istream_view(basic_istream<_CharT, _Traits>& __stream) |
801 | : _M_stream(std::__addressof(__stream)) |
802 | { } |
803 | |
804 | constexpr auto |
805 | begin() |
806 | { |
807 | *_M_stream >> _M_object; |
808 | return _Iterator{this}; |
809 | } |
810 | |
811 | constexpr default_sentinel_t |
812 | end() const noexcept |
813 | { return default_sentinel; } |
814 | |
815 | private: |
816 | basic_istream<_CharT, _Traits>* _M_stream; |
817 | _Val _M_object = _Val(); |
818 | |
819 | struct _Iterator |
820 | { |
821 | public: |
822 | using iterator_concept = input_iterator_tag; |
823 | using difference_type = ptrdiff_t; |
824 | using value_type = _Val; |
825 | |
826 | constexpr explicit |
827 | _Iterator(basic_istream_view* __parent) noexcept |
828 | : _M_parent(__parent) |
829 | { } |
830 | |
831 | _Iterator(const _Iterator&) = delete; |
832 | _Iterator(_Iterator&&) = default; |
833 | _Iterator& operator=(const _Iterator&) = delete; |
834 | _Iterator& operator=(_Iterator&&) = default; |
835 | |
836 | _Iterator& |
837 | operator++() |
838 | { |
839 | *_M_parent->_M_stream >> _M_parent->_M_object; |
840 | return *this; |
841 | } |
842 | |
843 | void |
844 | operator++(int) |
845 | { ++*this; } |
846 | |
847 | _Val& |
848 | operator*() const |
849 | { return _M_parent->_M_object; } |
850 | |
851 | friend bool |
852 | operator==(const _Iterator& __x, default_sentinel_t) |
853 | { return __x._M_at_end(); } |
854 | |
855 | private: |
856 | basic_istream_view* _M_parent; |
857 | |
858 | bool |
859 | _M_at_end() const |
860 | { return !*_M_parent->_M_stream; } |
861 | }; |
862 | |
863 | friend _Iterator; |
864 | }; |
865 | |
866 | template<typename _Val> |
867 | using istream_view = basic_istream_view<_Val, char>; |
868 | |
869 | template<typename _Val> |
870 | using wistream_view = basic_istream_view<_Val, wchar_t>; |
871 | |
872 | namespace views |
873 | { |
874 | namespace __detail |
875 | { |
876 | template<typename _Tp, typename _Up> |
877 | concept __can_istream_view = requires (_Up __e) { |
878 | basic_istream_view<_Tp, typename _Up::char_type, typename _Up::traits_type>(__e); |
879 | }; |
880 | } // namespace __detail |
881 | |
882 | template<typename _Tp> |
883 | struct _Istream |
884 | { |
885 | template<typename _CharT, typename _Traits> |
886 | constexpr auto |
887 | operator() [[nodiscard]] (basic_istream<_CharT, _Traits>& __e) const |
888 | requires __detail::__can_istream_view<_Tp, remove_reference_t<decltype(__e)>> |
889 | { return basic_istream_view<_Tp, _CharT, _Traits>(__e); } |
890 | }; |
891 | |
892 | template<typename _Tp> |
893 | inline constexpr _Istream<_Tp> istream; |
894 | } |
895 | #endif // HOSTED |
896 | |
897 | // C++20 24.7 [range.adaptors] Range adaptors |
898 | |
899 | namespace __detail |
900 | { |
901 | template<typename _Tp, int _Disc> |
902 | struct _Absent { }; |
903 | |
904 | // Alias for a type that is conditionally present |
905 | // (and is an empty type otherwise). |
906 | // Data members using this alias should use [[no_unique_address]] so that |
907 | // they take no space when not needed. |
908 | // The optional template parameter _Disc is for discriminating two otherwise |
909 | // equivalent absent types so that even they can overlap. |
910 | template<bool _Present, typename _Tp, int _Disc = 0> |
911 | using __maybe_present_t = __conditional_t<_Present, _Tp, _Absent<_Tp, _Disc>>; |
912 | |
913 | // Alias for a type that is conditionally const. |
914 | template<bool _Const, typename _Tp> |
915 | using __maybe_const_t = __conditional_t<_Const, const _Tp, _Tp>; |
916 | |
917 | } // namespace __detail |
918 | |
919 | // Shorthand for __detail::__maybe_const_t. |
920 | using __detail::__maybe_const_t; |
921 | |
922 | namespace views::__adaptor |
923 | { |
924 | // True if the range adaptor _Adaptor can be applied with _Args. |
925 | template<typename _Adaptor, typename... _Args> |
926 | concept __adaptor_invocable |
927 | = requires { std::declval<_Adaptor>()(declval<_Args>()...); }; |
928 | |
929 | // True if the range adaptor non-closure _Adaptor can be partially applied |
930 | // with _Args. |
931 | template<typename _Adaptor, typename... _Args> |
932 | concept __adaptor_partial_app_viable = (_Adaptor::_S_arity > 1) |
933 | && (sizeof...(_Args) == _Adaptor::_S_arity - 1) |
934 | && (constructible_from<decay_t<_Args>, _Args> && ...); |
935 | |
936 | template<typename _Adaptor, typename... _Args> |
937 | struct _Partial; |
938 | |
939 | template<typename _Lhs, typename _Rhs> |
940 | struct _Pipe; |
941 | |
942 | // The base class of every range adaptor closure. |
943 | // |
944 | // The derived class should define the optional static data member |
945 | // _S_has_simple_call_op to true if the behavior of this adaptor is |
946 | // independent of the constness/value category of the adaptor object. |
947 | template<typename _Derived> |
948 | struct _RangeAdaptorClosure |
949 | { }; |
950 | |
951 | template<typename _Tp, typename _Up> |
952 | requires (!same_as<_Tp, _RangeAdaptorClosure<_Up>>) |
953 | void __is_range_adaptor_closure_fn |
954 | (const _Tp&, const _RangeAdaptorClosure<_Up>&); // not defined |
955 | |
956 | template<typename _Tp> |
957 | concept __is_range_adaptor_closure |
958 | = requires (_Tp __t) { __adaptor::__is_range_adaptor_closure_fn(__t, __t); }; |
959 | |
960 | #pragma GCC diagnostic push |
961 | #pragma GCC diagnostic ignored "-Wdangling-reference" |
962 | // range | adaptor is equivalent to adaptor(range). |
963 | template<typename _Self, typename _Range> |
964 | requires __is_range_adaptor_closure<_Self> |
965 | && __adaptor_invocable<_Self, _Range> |
966 | constexpr auto |
967 | operator|(_Range&& __r, _Self&& __self) |
968 | { return std::forward<_Self>(__self)(std::forward<_Range>(__r)); } |
969 | |
970 | // Compose the adaptors __lhs and __rhs into a pipeline, returning |
971 | // another range adaptor closure object. |
972 | template<typename _Lhs, typename _Rhs> |
973 | requires __is_range_adaptor_closure<_Lhs> |
974 | && __is_range_adaptor_closure<_Rhs> |
975 | constexpr auto |
976 | operator|(_Lhs&& __lhs, _Rhs&& __rhs) |
977 | { |
978 | return _Pipe<decay_t<_Lhs>, decay_t<_Rhs>>{std::forward<_Lhs>(__lhs), |
979 | std::forward<_Rhs>(__rhs)}; |
980 | } |
981 | #pragma GCC diagnostic pop |
982 | |
983 | // The base class of every range adaptor non-closure. |
984 | // |
985 | // The static data member _Derived::_S_arity must contain the total number of |
986 | // arguments that the adaptor takes, and the class _Derived must introduce |
987 | // _RangeAdaptor::operator() into the class scope via a using-declaration. |
988 | // |
989 | // The optional static data member _Derived::_S_has_simple_extra_args should |
990 | // be defined to true if the behavior of this adaptor is independent of the |
991 | // constness/value category of the extra arguments. This data member could |
992 | // also be defined as a variable template parameterized by the types of the |
993 | // extra arguments. |
994 | template<typename _Derived> |
995 | struct _RangeAdaptor |
996 | { |
997 | // Partially apply the arguments __args to the range adaptor _Derived, |
998 | // returning a range adaptor closure object. |
999 | template<typename... _Args> |
1000 | requires __adaptor_partial_app_viable<_Derived, _Args...> |
1001 | constexpr auto |
1002 | operator()(_Args&&... __args) const |
1003 | { |
1004 | return _Partial<_Derived, decay_t<_Args>...>{0, std::forward<_Args>(__args)...}; |
1005 | } |
1006 | }; |
1007 | |
1008 | // True if the range adaptor closure _Adaptor has a simple operator(), i.e. |
1009 | // one that's not overloaded according to constness or value category of the |
1010 | // _Adaptor object. |
1011 | template<typename _Adaptor> |
1012 | concept __closure_has_simple_call_op = _Adaptor::_S_has_simple_call_op; |
1013 | |
1014 | // True if the behavior of the range adaptor non-closure _Adaptor is |
1015 | // independent of the value category of its extra arguments _Args. |
1016 | template<typename _Adaptor, typename... _Args> |
1017 | concept __adaptor_has_simple_extra_args = _Adaptor::_S_has_simple_extra_args |
1018 | || _Adaptor::template _S_has_simple_extra_args<_Args...>; |
1019 | |
1020 | // A range adaptor closure that represents partial application of |
1021 | // the range adaptor _Adaptor with arguments _Args. |
1022 | template<typename _Adaptor, typename... _Args> |
1023 | struct _Partial : _RangeAdaptorClosure<_Partial<_Adaptor, _Args...>> |
1024 | { |
1025 | tuple<_Args...> _M_args; |
1026 | |
1027 | // First parameter is to ensure this constructor is never used |
1028 | // instead of the copy/move constructor. |
1029 | template<typename... _Ts> |
1030 | constexpr |
1031 | _Partial(int, _Ts&&... __args) |
1032 | : _M_args(std::forward<_Ts>(__args)...) |
1033 | { } |
1034 | |
1035 | // Invoke _Adaptor with arguments __r, _M_args... according to the |
1036 | // value category of this _Partial object. |
1037 | #if __cpp_explicit_this_parameter |
1038 | template<typename _Self, typename _Range> |
1039 | requires __adaptor_invocable<_Adaptor, _Range, __like_t<_Self, _Args>...> |
1040 | constexpr auto |
1041 | operator()(this _Self&& __self, _Range&& __r) |
1042 | { |
1043 | auto __forwarder = [&__r] (auto&&... __args) { |
1044 | return _Adaptor{}(std::forward<_Range>(__r), |
1045 | std::forward<decltype(__args)>(__args)...); |
1046 | }; |
1047 | return std::apply(__forwarder, __like_t<_Self, _Partial>(__self)._M_args); |
1048 | } |
1049 | #else |
1050 | template<typename _Range> |
1051 | requires __adaptor_invocable<_Adaptor, _Range, const _Args&...> |
1052 | constexpr auto |
1053 | operator()(_Range&& __r) const & |
1054 | { |
1055 | auto __forwarder = [&__r] (const auto&... __args) { |
1056 | return _Adaptor{}(std::forward<_Range>(__r), __args...); |
1057 | }; |
1058 | return std::apply(__forwarder, _M_args); |
1059 | } |
1060 | |
1061 | template<typename _Range> |
1062 | requires __adaptor_invocable<_Adaptor, _Range, _Args...> |
1063 | constexpr auto |
1064 | operator()(_Range&& __r) && |
1065 | { |
1066 | auto __forwarder = [&__r] (auto&... __args) { |
1067 | return _Adaptor{}(std::forward<_Range>(__r), std::move(__args)...); |
1068 | }; |
1069 | return std::apply(__forwarder, _M_args); |
1070 | } |
1071 | |
1072 | template<typename _Range> |
1073 | constexpr auto |
1074 | operator()(_Range&& __r) const && = delete; |
1075 | #endif |
1076 | }; |
1077 | |
1078 | // A lightweight specialization of the above primary template for |
1079 | // the common case where _Adaptor accepts a single extra argument. |
1080 | template<typename _Adaptor, typename _Arg> |
1081 | struct _Partial<_Adaptor, _Arg> : _RangeAdaptorClosure<_Partial<_Adaptor, _Arg>> |
1082 | { |
1083 | _Arg _M_arg; |
1084 | |
1085 | template<typename _Tp> |
1086 | constexpr |
1087 | _Partial(int, _Tp&& __arg) |
1088 | : _M_arg(std::forward<_Tp>(__arg)) |
1089 | { } |
1090 | |
1091 | #if __cpp_explicit_this_parameter |
1092 | template<typename _Self, typename _Range> |
1093 | requires __adaptor_invocable<_Adaptor, _Range, __like_t<_Self, _Arg>> |
1094 | constexpr auto |
1095 | operator()(this _Self&& __self, _Range&& __r) |
1096 | { |
1097 | return _Adaptor{}(std::forward<_Range>(__r), |
1098 | __like_t<_Self, _Partial>(__self)._M_arg); |
1099 | } |
1100 | #else |
1101 | template<typename _Range> |
1102 | requires __adaptor_invocable<_Adaptor, _Range, const _Arg&> |
1103 | constexpr auto |
1104 | operator()(_Range&& __r) const & |
1105 | { return _Adaptor{}(std::forward<_Range>(__r), _M_arg); } |
1106 | |
1107 | template<typename _Range> |
1108 | requires __adaptor_invocable<_Adaptor, _Range, _Arg> |
1109 | constexpr auto |
1110 | operator()(_Range&& __r) && |
1111 | { return _Adaptor{}(std::forward<_Range>(__r), std::move(_M_arg)); } |
1112 | |
1113 | template<typename _Range> |
1114 | constexpr auto |
1115 | operator()(_Range&& __r) const && = delete; |
1116 | #endif |
1117 | }; |
1118 | |
1119 | // Partial specialization of the primary template for the case where the extra |
1120 | // arguments of the adaptor can always be safely and efficiently forwarded by |
1121 | // const reference. This lets us get away with a single operator() overload, |
1122 | // which makes overload resolution failure diagnostics more concise. |
1123 | template<typename _Adaptor, typename... _Args> |
1124 | requires __adaptor_has_simple_extra_args<_Adaptor, _Args...> |
1125 | && (is_trivially_copy_constructible_v<_Args> && ...) |
1126 | struct _Partial<_Adaptor, _Args...> : _RangeAdaptorClosure<_Partial<_Adaptor, _Args...>> |
1127 | { |
1128 | tuple<_Args...> _M_args; |
1129 | |
1130 | template<typename... _Ts> |
1131 | constexpr |
1132 | _Partial(int, _Ts&&... __args) |
1133 | : _M_args(std::forward<_Ts>(__args)...) |
1134 | { } |
1135 | |
1136 | // Invoke _Adaptor with arguments __r, const _M_args&... regardless |
1137 | // of the value category of this _Partial object. |
1138 | template<typename _Range> |
1139 | requires __adaptor_invocable<_Adaptor, _Range, const _Args&...> |
1140 | constexpr auto |
1141 | operator()(_Range&& __r) const |
1142 | { |
1143 | auto __forwarder = [&__r] (const auto&... __args) { |
1144 | return _Adaptor{}(std::forward<_Range>(__r), __args...); |
1145 | }; |
1146 | return std::apply(__forwarder, _M_args); |
1147 | } |
1148 | |
1149 | static constexpr bool _S_has_simple_call_op = true; |
1150 | }; |
1151 | |
1152 | // A lightweight specialization of the above template for the common case |
1153 | // where _Adaptor accepts a single extra argument. |
1154 | template<typename _Adaptor, typename _Arg> |
1155 | requires __adaptor_has_simple_extra_args<_Adaptor, _Arg> |
1156 | && is_trivially_copy_constructible_v<_Arg> |
1157 | struct _Partial<_Adaptor, _Arg> : _RangeAdaptorClosure<_Partial<_Adaptor, _Arg>> |
1158 | { |
1159 | _Arg _M_arg; |
1160 | |
1161 | template<typename _Tp> |
1162 | constexpr |
1163 | _Partial(int, _Tp&& __arg) |
1164 | : _M_arg(std::forward<_Tp>(__arg)) |
1165 | { } |
1166 | |
1167 | template<typename _Range> |
1168 | requires __adaptor_invocable<_Adaptor, _Range, const _Arg&> |
1169 | constexpr auto |
1170 | operator()(_Range&& __r) const |
1171 | { return _Adaptor{}(std::forward<_Range>(__r), _M_arg); } |
1172 | |
1173 | static constexpr bool _S_has_simple_call_op = true; |
1174 | }; |
1175 | |
1176 | template<typename _Lhs, typename _Rhs, typename _Range> |
1177 | concept __pipe_invocable |
1178 | = requires { std::declval<_Rhs>()(std::declval<_Lhs>()(std::declval<_Range>())); }; |
1179 | |
1180 | // A range adaptor closure that represents composition of the range |
1181 | // adaptor closures _Lhs and _Rhs. |
1182 | template<typename _Lhs, typename _Rhs> |
1183 | struct _Pipe : _RangeAdaptorClosure<_Pipe<_Lhs, _Rhs>> |
1184 | { |
1185 | [[no_unique_address]] _Lhs _M_lhs; |
1186 | [[no_unique_address]] _Rhs _M_rhs; |
1187 | |
1188 | template<typename _Tp, typename _Up> |
1189 | constexpr |
1190 | _Pipe(_Tp&& __lhs, _Up&& __rhs) |
1191 | : _M_lhs(std::forward<_Tp>(__lhs)), _M_rhs(std::forward<_Up>(__rhs)) |
1192 | { } |
1193 | |
1194 | // Invoke _M_rhs(_M_lhs(__r)) according to the value category of this |
1195 | // range adaptor closure object. |
1196 | #if __cpp_explicit_this_parameter |
1197 | template<typename _Self, typename _Range> |
1198 | requires __pipe_invocable<__like_t<_Self, _Lhs>, __like_t<_Self, _Rhs>, _Range> |
1199 | constexpr auto |
1200 | operator()(this _Self&& __self, _Range&& __r) |
1201 | { |
1202 | return (__like_t<_Self, _Pipe>(__self)._M_rhs |
1203 | (__like_t<_Self, _Pipe>(__self)._M_lhs |
1204 | (std::forward<_Range>(__r)))); |
1205 | } |
1206 | #else |
1207 | template<typename _Range> |
1208 | requires __pipe_invocable<const _Lhs&, const _Rhs&, _Range> |
1209 | constexpr auto |
1210 | operator()(_Range&& __r) const & |
1211 | { return _M_rhs(_M_lhs(std::forward<_Range>(__r))); } |
1212 | |
1213 | template<typename _Range> |
1214 | requires __pipe_invocable<_Lhs, _Rhs, _Range> |
1215 | constexpr auto |
1216 | operator()(_Range&& __r) && |
1217 | { return std::move(_M_rhs)(std::move(_M_lhs)(std::forward<_Range>(__r))); } |
1218 | |
1219 | template<typename _Range> |
1220 | constexpr auto |
1221 | operator()(_Range&& __r) const && = delete; |
1222 | #endif |
1223 | }; |
1224 | |
1225 | // A partial specialization of the above primary template for the case where |
1226 | // both adaptor operands have a simple operator(). This in turn lets us |
1227 | // implement composition using a single simple operator(), which makes |
1228 | // overload resolution failure diagnostics more concise. |
1229 | template<typename _Lhs, typename _Rhs> |
1230 | requires __closure_has_simple_call_op<_Lhs> |
1231 | && __closure_has_simple_call_op<_Rhs> |
1232 | struct _Pipe<_Lhs, _Rhs> : _RangeAdaptorClosure<_Pipe<_Lhs, _Rhs>> |
1233 | { |
1234 | [[no_unique_address]] _Lhs _M_lhs; |
1235 | [[no_unique_address]] _Rhs _M_rhs; |
1236 | |
1237 | template<typename _Tp, typename _Up> |
1238 | constexpr |
1239 | _Pipe(_Tp&& __lhs, _Up&& __rhs) |
1240 | : _M_lhs(std::forward<_Tp>(__lhs)), _M_rhs(std::forward<_Up>(__rhs)) |
1241 | { } |
1242 | |
1243 | template<typename _Range> |
1244 | requires __pipe_invocable<const _Lhs&, const _Rhs&, _Range> |
1245 | constexpr auto |
1246 | operator()(_Range&& __r) const |
1247 | { return _M_rhs(_M_lhs(std::forward<_Range>(__r))); } |
1248 | |
1249 | static constexpr bool _S_has_simple_call_op = true; |
1250 | }; |
1251 | } // namespace views::__adaptor |
1252 | |
1253 | #if __cpp_lib_ranges >= 202202L |
1254 | // P2387R3 Pipe support for user-defined range adaptors |
1255 | template<typename _Derived> |
1256 | requires is_class_v<_Derived> && same_as<_Derived, remove_cv_t<_Derived>> |
1257 | class range_adaptor_closure |
1258 | : public views::__adaptor::_RangeAdaptorClosure<_Derived> |
1259 | { }; |
1260 | #endif |
1261 | |
1262 | template<range _Range> requires is_object_v<_Range> |
1263 | class ref_view : public view_interface<ref_view<_Range>> |
1264 | { |
1265 | private: |
1266 | _Range* _M_r; |
1267 | |
1268 | static void _S_fun(_Range&); // not defined |
1269 | static void _S_fun(_Range&&) = delete; |
1270 | |
1271 | public: |
1272 | template<__detail::__different_from<ref_view> _Tp> |
1273 | requires convertible_to<_Tp, _Range&> |
1274 | && requires { _S_fun(declval<_Tp>()); } |
1275 | constexpr |
1276 | ref_view(_Tp&& __t) |
1277 | noexcept(noexcept(static_cast<_Range&>(std::declval<_Tp>()))) |
1278 | : _M_r(std::__addressof(static_cast<_Range&>(std::forward<_Tp>(__t)))) |
1279 | { } |
1280 | |
1281 | constexpr _Range& |
1282 | base() const |
1283 | { return *_M_r; } |
1284 | |
1285 | constexpr iterator_t<_Range> |
1286 | begin() const |
1287 | { return ranges::begin(*_M_r); } |
1288 | |
1289 | constexpr sentinel_t<_Range> |
1290 | end() const |
1291 | { return ranges::end(*_M_r); } |
1292 | |
1293 | constexpr bool |
1294 | empty() const requires requires { ranges::empty(*_M_r); } |
1295 | { return ranges::empty(*_M_r); } |
1296 | |
1297 | constexpr auto |
1298 | size() const requires sized_range<_Range> |
1299 | { return ranges::size(*_M_r); } |
1300 | |
1301 | constexpr auto |
1302 | data() const requires contiguous_range<_Range> |
1303 | { return ranges::data(*_M_r); } |
1304 | }; |
1305 | |
1306 | template<typename _Range> |
1307 | ref_view(_Range&) -> ref_view<_Range>; |
1308 | |
1309 | template<typename _Tp> |
1310 | inline constexpr bool enable_borrowed_range<ref_view<_Tp>> = true; |
1311 | |
1312 | template<range _Range> |
1313 | requires movable<_Range> |
1314 | && (!__detail::__is_initializer_list<remove_cv_t<_Range>>) |
1315 | class owning_view : public view_interface<owning_view<_Range>> |
1316 | { |
1317 | private: |
1318 | _Range _M_r = _Range(); |
1319 | |
1320 | public: |
1321 | owning_view() requires default_initializable<_Range> = default; |
1322 | |
1323 | constexpr |
1324 | owning_view(_Range&& __t) |
1325 | noexcept(is_nothrow_move_constructible_v<_Range>) |
1326 | : _M_r(std::move(__t)) |
1327 | { } |
1328 | |
1329 | owning_view(owning_view&&) = default; |
1330 | owning_view& operator=(owning_view&&) = default; |
1331 | |
1332 | constexpr _Range& |
1333 | base() & noexcept |
1334 | { return _M_r; } |
1335 | |
1336 | constexpr const _Range& |
1337 | base() const& noexcept |
1338 | { return _M_r; } |
1339 | |
1340 | constexpr _Range&& |
1341 | base() && noexcept |
1342 | { return std::move(_M_r); } |
1343 | |
1344 | constexpr const _Range&& |
1345 | base() const&& noexcept |
1346 | { return std::move(_M_r); } |
1347 | |
1348 | constexpr iterator_t<_Range> |
1349 | begin() |
1350 | { return ranges::begin(_M_r); } |
1351 | |
1352 | constexpr sentinel_t<_Range> |
1353 | end() |
1354 | { return ranges::end(_M_r); } |
1355 | |
1356 | constexpr auto |
1357 | begin() const requires range<const _Range> |
1358 | { return ranges::begin(_M_r); } |
1359 | |
1360 | constexpr auto |
1361 | end() const requires range<const _Range> |
1362 | { return ranges::end(_M_r); } |
1363 | |
1364 | constexpr bool |
1365 | empty() requires requires { ranges::empty(_M_r); } |
1366 | { return ranges::empty(_M_r); } |
1367 | |
1368 | constexpr bool |
1369 | empty() const requires requires { ranges::empty(_M_r); } |
1370 | { return ranges::empty(_M_r); } |
1371 | |
1372 | constexpr auto |
1373 | size() requires sized_range<_Range> |
1374 | { return ranges::size(_M_r); } |
1375 | |
1376 | constexpr auto |
1377 | size() const requires sized_range<const _Range> |
1378 | { return ranges::size(_M_r); } |
1379 | |
1380 | constexpr auto |
1381 | data() requires contiguous_range<_Range> |
1382 | { return ranges::data(_M_r); } |
1383 | |
1384 | constexpr auto |
1385 | data() const requires contiguous_range<const _Range> |
1386 | { return ranges::data(_M_r); } |
1387 | }; |
1388 | |
1389 | template<typename _Tp> |
1390 | inline constexpr bool enable_borrowed_range<owning_view<_Tp>> |
1391 | = enable_borrowed_range<_Tp>; |
1392 | |
1393 | namespace views |
1394 | { |
1395 | namespace __detail |
1396 | { |
1397 | template<typename _Range> |
1398 | concept __can_ref_view = requires { ref_view{std::declval<_Range>()}; }; |
1399 | |
1400 | template<typename _Range> |
1401 | concept __can_owning_view = requires { owning_view{std::declval<_Range>()}; }; |
1402 | } // namespace __detail |
1403 | |
1404 | struct _All : __adaptor::_RangeAdaptorClosure<_All> |
1405 | { |
1406 | template<typename _Range> |
1407 | static constexpr bool |
1408 | _S_noexcept() |
1409 | { |
1410 | if constexpr (view<decay_t<_Range>>) |
1411 | return is_nothrow_constructible_v<decay_t<_Range>, _Range>; |
1412 | else if constexpr (__detail::__can_ref_view<_Range>) |
1413 | return true; |
1414 | else |
1415 | return noexcept(owning_view{std::declval<_Range>()}); |
1416 | } |
1417 | |
1418 | template<viewable_range _Range> |
1419 | requires view<decay_t<_Range>> |
1420 | || __detail::__can_ref_view<_Range> |
1421 | || __detail::__can_owning_view<_Range> |
1422 | constexpr auto |
1423 | operator() [[nodiscard]] (_Range&& __r) const |
1424 | noexcept(_S_noexcept<_Range>()) |
1425 | { |
1426 | if constexpr (view<decay_t<_Range>>) |
1427 | return std::forward<_Range>(__r); |
1428 | else if constexpr (__detail::__can_ref_view<_Range>) |
1429 | return ref_view{std::forward<_Range>(__r)}; |
1430 | else |
1431 | return owning_view{std::forward<_Range>(__r)}; |
1432 | } |
1433 | |
1434 | static constexpr bool _S_has_simple_call_op = true; |
1435 | }; |
1436 | |
1437 | inline constexpr _All all; |
1438 | |
1439 | template<viewable_range _Range> |
1440 | using all_t = decltype(all(std::declval<_Range>())); |
1441 | } // namespace views |
1442 | |
1443 | namespace __detail |
1444 | { |
1445 | template<typename _Tp> |
1446 | struct __non_propagating_cache |
1447 | { |
1448 | // When _Tp is not an object type (e.g. is a reference type), we make |
1449 | // __non_propagating_cache<_Tp> empty rather than ill-formed so that |
1450 | // users can easily conditionally declare data members with this type |
1451 | // (such as join_view::_M_inner). |
1452 | }; |
1453 | |
1454 | template<typename _Tp> |
1455 | requires is_object_v<_Tp> |
1456 | struct __non_propagating_cache<_Tp> |
1457 | : protected _Optional_base<_Tp> |
1458 | { |
1459 | __non_propagating_cache() = default; |
1460 | |
1461 | constexpr |
1462 | __non_propagating_cache(const __non_propagating_cache&) noexcept |
1463 | { } |
1464 | |
1465 | constexpr |
1466 | __non_propagating_cache(__non_propagating_cache&& __other) noexcept |
1467 | { __other._M_reset(); } |
1468 | |
1469 | constexpr __non_propagating_cache& |
1470 | operator=(const __non_propagating_cache& __other) noexcept |
1471 | { |
1472 | if (std::__addressof(__other) != this) |
1473 | this->_M_reset(); |
1474 | return *this; |
1475 | } |
1476 | |
1477 | constexpr __non_propagating_cache& |
1478 | operator=(__non_propagating_cache&& __other) noexcept |
1479 | { |
1480 | this->_M_reset(); |
1481 | __other._M_reset(); |
1482 | return *this; |
1483 | } |
1484 | |
1485 | constexpr __non_propagating_cache& |
1486 | operator=(_Tp __val) |
1487 | { |
1488 | this->_M_reset(); |
1489 | this->_M_payload._M_construct(std::move(__val)); |
1490 | return *this; |
1491 | } |
1492 | |
1493 | constexpr explicit |
1494 | operator bool() const noexcept |
1495 | { return this->_M_is_engaged(); } |
1496 | |
1497 | constexpr _Tp& |
1498 | operator*() noexcept |
1499 | { return this->_M_get(); } |
1500 | |
1501 | constexpr const _Tp& |
1502 | operator*() const noexcept |
1503 | { return this->_M_get(); } |
1504 | |
1505 | template<typename _Iter> |
1506 | constexpr _Tp& |
1507 | _M_emplace_deref(const _Iter& __i) |
1508 | { |
1509 | this->_M_reset(); |
1510 | auto __f = [] (auto& __x) { return *__x; }; |
1511 | this->_M_payload._M_apply(_Optional_func{__f}, __i); |
1512 | return this->_M_get(); |
1513 | } |
1514 | }; |
1515 | |
1516 | template<range _Range> |
1517 | struct _CachedPosition |
1518 | { |
1519 | constexpr bool |
1520 | _M_has_value() const |
1521 | { return false; } |
1522 | |
1523 | constexpr iterator_t<_Range> |
1524 | _M_get(const _Range&) const |
1525 | { |
1526 | __glibcxx_assert(false); |
1527 | __builtin_unreachable(); |
1528 | } |
1529 | |
1530 | constexpr void |
1531 | _M_set(const _Range&, const iterator_t<_Range>&) const |
1532 | { } |
1533 | }; |
1534 | |
1535 | template<forward_range _Range> |
1536 | struct _CachedPosition<_Range> |
1537 | : protected __non_propagating_cache<iterator_t<_Range>> |
1538 | { |
1539 | constexpr bool |
1540 | _M_has_value() const |
1541 | { return this->_M_is_engaged(); } |
1542 | |
1543 | constexpr iterator_t<_Range> |
1544 | _M_get(const _Range&) const |
1545 | { |
1546 | __glibcxx_assert(_M_has_value()); |
1547 | return **this; |
1548 | } |
1549 | |
1550 | constexpr void |
1551 | _M_set(const _Range&, const iterator_t<_Range>& __it) |
1552 | { |
1553 | __glibcxx_assert(!_M_has_value()); |
1554 | std::construct_at(std::__addressof(this->_M_payload._M_payload), |
1555 | in_place, __it); |
1556 | this->_M_payload._M_engaged = true; |
1557 | } |
1558 | }; |
1559 | |
1560 | template<random_access_range _Range> |
1561 | requires (sizeof(range_difference_t<_Range>) |
1562 | <= sizeof(iterator_t<_Range>)) |
1563 | struct _CachedPosition<_Range> |
1564 | { |
1565 | private: |
1566 | range_difference_t<_Range> _M_offset = -1; |
1567 | |
1568 | public: |
1569 | _CachedPosition() = default; |
1570 | |
1571 | constexpr |
1572 | _CachedPosition(const _CachedPosition&) = default; |
1573 | |
1574 | constexpr |
1575 | _CachedPosition(_CachedPosition&& __other) noexcept |
1576 | { *this = std::move(__other); } |
1577 | |
1578 | constexpr _CachedPosition& |
1579 | operator=(const _CachedPosition&) = default; |
1580 | |
1581 | constexpr _CachedPosition& |
1582 | operator=(_CachedPosition&& __other) noexcept |
1583 | { |
1584 | // Propagate the cached offset, but invalidate the source. |
1585 | _M_offset = __other._M_offset; |
1586 | __other._M_offset = -1; |
1587 | return *this; |
1588 | } |
1589 | |
1590 | constexpr bool |
1591 | _M_has_value() const |
1592 | { return _M_offset >= 0; } |
1593 | |
1594 | constexpr iterator_t<_Range> |
1595 | _M_get(_Range& __r) const |
1596 | { |
1597 | __glibcxx_assert(_M_has_value()); |
1598 | return ranges::begin(__r) + _M_offset; |
1599 | } |
1600 | |
1601 | constexpr void |
1602 | _M_set(_Range& __r, const iterator_t<_Range>& __it) |
1603 | { |
1604 | __glibcxx_assert(!_M_has_value()); |
1605 | _M_offset = __it - ranges::begin(__r); |
1606 | } |
1607 | }; |
1608 | } // namespace __detail |
1609 | |
1610 | namespace __detail |
1611 | { |
1612 | template<typename _Base> |
1613 | struct __filter_view_iter_cat |
1614 | { }; |
1615 | |
1616 | template<forward_range _Base> |
1617 | struct __filter_view_iter_cat<_Base> |
1618 | { |
1619 | private: |
1620 | static auto |
1621 | _S_iter_cat() |
1622 | { |
1623 | using _Cat = typename iterator_traits<iterator_t<_Base>>::iterator_category; |
1624 | if constexpr (derived_from<_Cat, bidirectional_iterator_tag>) |
1625 | return bidirectional_iterator_tag{}; |
1626 | else if constexpr (derived_from<_Cat, forward_iterator_tag>) |
1627 | return forward_iterator_tag{}; |
1628 | else |
1629 | return _Cat{}; |
1630 | } |
1631 | public: |
1632 | using iterator_category = decltype(_S_iter_cat()); |
1633 | }; |
1634 | } // namespace __detail |
1635 | |
1636 | template<input_range _Vp, |
1637 | indirect_unary_predicate<iterator_t<_Vp>> _Pred> |
1638 | requires view<_Vp> && is_object_v<_Pred> |
1639 | class filter_view : public view_interface<filter_view<_Vp, _Pred>> |
1640 | { |
1641 | private: |
1642 | struct _Sentinel; |
1643 | |
1644 | struct _Iterator : __detail::__filter_view_iter_cat<_Vp> |
1645 | { |
1646 | private: |
1647 | static constexpr auto |
1648 | _S_iter_concept() |
1649 | { |
1650 | if constexpr (bidirectional_range<_Vp>) |
1651 | return bidirectional_iterator_tag{}; |
1652 | else if constexpr (forward_range<_Vp>) |
1653 | return forward_iterator_tag{}; |
1654 | else |
1655 | return input_iterator_tag{}; |
1656 | } |
1657 | |
1658 | friend filter_view; |
1659 | |
1660 | using _Vp_iter = iterator_t<_Vp>; |
1661 | |
1662 | _Vp_iter _M_current = _Vp_iter(); |
1663 | filter_view* _M_parent = nullptr; |
1664 | |
1665 | public: |
1666 | using iterator_concept = decltype(_S_iter_concept()); |
1667 | // iterator_category defined in __filter_view_iter_cat |
1668 | using value_type = range_value_t<_Vp>; |
1669 | using difference_type = range_difference_t<_Vp>; |
1670 | |
1671 | _Iterator() requires default_initializable<_Vp_iter> = default; |
1672 | |
1673 | constexpr |
1674 | _Iterator(filter_view* __parent, _Vp_iter __current) |
1675 | : _M_current(std::move(__current)), |
1676 | _M_parent(__parent) |
1677 | { } |
1678 | |
1679 | constexpr const _Vp_iter& |
1680 | base() const & noexcept |
1681 | { return _M_current; } |
1682 | |
1683 | constexpr _Vp_iter |
1684 | base() && |
1685 | { return std::move(_M_current); } |
1686 | |
1687 | constexpr range_reference_t<_Vp> |
1688 | operator*() const |
1689 | { return *_M_current; } |
1690 | |
1691 | constexpr _Vp_iter |
1692 | operator->() const |
1693 | requires __detail::__has_arrow<_Vp_iter> |
1694 | && copyable<_Vp_iter> |
1695 | { return _M_current; } |
1696 | |
1697 | constexpr _Iterator& |
1698 | operator++() |
1699 | { |
1700 | _M_current = ranges::find_if(std::move(++_M_current), |
1701 | ranges::end(_M_parent->_M_base), |
1702 | std::ref(*_M_parent->_M_pred)); |
1703 | return *this; |
1704 | } |
1705 | |
1706 | constexpr void |
1707 | operator++(int) |
1708 | { ++*this; } |
1709 | |
1710 | constexpr _Iterator |
1711 | operator++(int) requires forward_range<_Vp> |
1712 | { |
1713 | auto __tmp = *this; |
1714 | ++*this; |
1715 | return __tmp; |
1716 | } |
1717 | |
1718 | constexpr _Iterator& |
1719 | operator--() requires bidirectional_range<_Vp> |
1720 | { |
1721 | do |
1722 | --_M_current; |
1723 | while (!std::__invoke(*_M_parent->_M_pred, *_M_current)); |
1724 | return *this; |
1725 | } |
1726 | |
1727 | constexpr _Iterator |
1728 | operator--(int) requires bidirectional_range<_Vp> |
1729 | { |
1730 | auto __tmp = *this; |
1731 | --*this; |
1732 | return __tmp; |
1733 | } |
1734 | |
1735 | friend constexpr bool |
1736 | operator==(const _Iterator& __x, const _Iterator& __y) |
1737 | requires equality_comparable<_Vp_iter> |
1738 | { return __x._M_current == __y._M_current; } |
1739 | |
1740 | friend constexpr range_rvalue_reference_t<_Vp> |
1741 | iter_move(const _Iterator& __i) |
1742 | noexcept(noexcept(ranges::iter_move(__i._M_current))) |
1743 | { return ranges::iter_move(__i._M_current); } |
1744 | |
1745 | friend constexpr void |
1746 | iter_swap(const _Iterator& __x, const _Iterator& __y) |
1747 | noexcept(noexcept(ranges::iter_swap(__x._M_current, __y._M_current))) |
1748 | requires indirectly_swappable<_Vp_iter> |
1749 | { ranges::iter_swap(__x._M_current, __y._M_current); } |
1750 | }; |
1751 | |
1752 | struct _Sentinel |
1753 | { |
1754 | private: |
1755 | sentinel_t<_Vp> _M_end = sentinel_t<_Vp>(); |
1756 | |
1757 | constexpr bool |
1758 | __equal(const _Iterator& __i) const |
1759 | { return __i._M_current == _M_end; } |
1760 | |
1761 | public: |
1762 | _Sentinel() = default; |
1763 | |
1764 | constexpr explicit |
1765 | _Sentinel(filter_view* __parent) |
1766 | : _M_end(ranges::end(__parent->_M_base)) |
1767 | { } |
1768 | |
1769 | constexpr sentinel_t<_Vp> |
1770 | base() const |
1771 | { return _M_end; } |
1772 | |
1773 | friend constexpr bool |
1774 | operator==(const _Iterator& __x, const _Sentinel& __y) |
1775 | { return __y.__equal(__x); } |
1776 | }; |
1777 | |
1778 | _Vp _M_base = _Vp(); |
1779 | [[no_unique_address]] __detail::__box<_Pred> _M_pred; |
1780 | [[no_unique_address]] __detail::_CachedPosition<_Vp> _M_cached_begin; |
1781 | |
1782 | public: |
1783 | filter_view() requires (default_initializable<_Vp> |
1784 | && default_initializable<_Pred>) |
1785 | = default; |
1786 | |
1787 | constexpr |
1788 | filter_view(_Vp __base, _Pred __pred) |
1789 | : _M_base(std::move(__base)), _M_pred(std::move(__pred)) |
1790 | { } |
1791 | |
1792 | constexpr _Vp |
1793 | base() const& requires copy_constructible<_Vp> |
1794 | { return _M_base; } |
1795 | |
1796 | constexpr _Vp |
1797 | base() && |
1798 | { return std::move(_M_base); } |
1799 | |
1800 | constexpr const _Pred& |
1801 | pred() const |
1802 | { return *_M_pred; } |
1803 | |
1804 | constexpr _Iterator |
1805 | begin() |
1806 | { |
1807 | if (_M_cached_begin._M_has_value()) |
1808 | return {this, _M_cached_begin._M_get(_M_base)}; |
1809 | |
1810 | __glibcxx_assert(_M_pred.has_value()); |
1811 | auto __it = ranges::find_if(ranges::begin(_M_base), |
1812 | ranges::end(_M_base), |
1813 | std::ref(*_M_pred)); |
1814 | _M_cached_begin._M_set(_M_base, __it); |
1815 | return {this, std::move(__it)}; |
1816 | } |
1817 | |
1818 | constexpr auto |
1819 | end() |
1820 | { |
1821 | if constexpr (common_range<_Vp>) |
1822 | return _Iterator{this, ranges::end(_M_base)}; |
1823 | else |
1824 | return _Sentinel{this}; |
1825 | } |
1826 | }; |
1827 | |
1828 | template<typename _Range, typename _Pred> |
1829 | filter_view(_Range&&, _Pred) -> filter_view<views::all_t<_Range>, _Pred>; |
1830 | |
1831 | namespace views |
1832 | { |
1833 | namespace __detail |
1834 | { |
1835 | template<typename _Range, typename _Pred> |
1836 | concept __can_filter_view |
1837 | = requires { filter_view(std::declval<_Range>(), std::declval<_Pred>()); }; |
1838 | } // namespace __detail |
1839 | |
1840 | struct _Filter : __adaptor::_RangeAdaptor<_Filter> |
1841 | { |
1842 | template<viewable_range _Range, typename _Pred> |
1843 | requires __detail::__can_filter_view<_Range, _Pred> |
1844 | constexpr auto |
1845 | operator() [[nodiscard]] (_Range&& __r, _Pred&& __p) const |
1846 | { |
1847 | return filter_view(std::forward<_Range>(__r), std::forward<_Pred>(__p)); |
1848 | } |
1849 | |
1850 | using _RangeAdaptor<_Filter>::operator(); |
1851 | static constexpr int _S_arity = 2; |
1852 | static constexpr bool = true; |
1853 | }; |
1854 | |
1855 | inline constexpr _Filter filter; |
1856 | } // namespace views |
1857 | |
1858 | #if __cpp_lib_ranges >= 202207L // C++ >= 23 |
1859 | template<input_range _Vp, move_constructible _Fp> |
1860 | #else |
1861 | template<input_range _Vp, copy_constructible _Fp> |
1862 | #endif |
1863 | requires view<_Vp> && is_object_v<_Fp> |
1864 | && regular_invocable<_Fp&, range_reference_t<_Vp>> |
1865 | && std::__detail::__can_reference<invoke_result_t<_Fp&, |
1866 | range_reference_t<_Vp>>> |
1867 | class transform_view : public view_interface<transform_view<_Vp, _Fp>> |
1868 | { |
1869 | private: |
1870 | template<bool _Const> |
1871 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
1872 | |
1873 | template<bool _Const> |
1874 | struct __iter_cat |
1875 | { }; |
1876 | |
1877 | template<bool _Const> |
1878 | requires forward_range<_Base<_Const>> |
1879 | struct __iter_cat<_Const> |
1880 | { |
1881 | private: |
1882 | static auto |
1883 | _S_iter_cat() |
1884 | { |
1885 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
1886 | // 3564. transform_view::iterator<true>::value_type and |
1887 | // iterator_category should use const F& |
1888 | using _Base = transform_view::_Base<_Const>; |
1889 | using _Res = invoke_result_t<__maybe_const_t<_Const, _Fp>&, |
1890 | range_reference_t<_Base>>; |
1891 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
1892 | // 3798. Rvalue reference and iterator_category |
1893 | if constexpr (is_reference_v<_Res>) |
1894 | { |
1895 | using _Cat |
1896 | = typename iterator_traits<iterator_t<_Base>>::iterator_category; |
1897 | if constexpr (derived_from<_Cat, contiguous_iterator_tag>) |
1898 | return random_access_iterator_tag{}; |
1899 | else |
1900 | return _Cat{}; |
1901 | } |
1902 | else |
1903 | return input_iterator_tag{}; |
1904 | } |
1905 | public: |
1906 | using iterator_category = decltype(_S_iter_cat()); |
1907 | }; |
1908 | |
1909 | template<bool _Const> |
1910 | struct _Sentinel; |
1911 | |
1912 | template<bool _Const> |
1913 | struct _Iterator : __iter_cat<_Const> |
1914 | { |
1915 | private: |
1916 | using _Parent = __detail::__maybe_const_t<_Const, transform_view>; |
1917 | using _Base = transform_view::_Base<_Const>; |
1918 | |
1919 | static auto |
1920 | _S_iter_concept() |
1921 | { |
1922 | if constexpr (random_access_range<_Base>) |
1923 | return random_access_iterator_tag{}; |
1924 | else if constexpr (bidirectional_range<_Base>) |
1925 | return bidirectional_iterator_tag{}; |
1926 | else if constexpr (forward_range<_Base>) |
1927 | return forward_iterator_tag{}; |
1928 | else |
1929 | return input_iterator_tag{}; |
1930 | } |
1931 | |
1932 | using _Base_iter = iterator_t<_Base>; |
1933 | |
1934 | _Base_iter _M_current = _Base_iter(); |
1935 | _Parent* _M_parent = nullptr; |
1936 | |
1937 | public: |
1938 | using iterator_concept = decltype(_S_iter_concept()); |
1939 | // iterator_category defined in __transform_view_iter_cat |
1940 | using value_type |
1941 | = remove_cvref_t<invoke_result_t<__maybe_const_t<_Const, _Fp>&, |
1942 | range_reference_t<_Base>>>; |
1943 | using difference_type = range_difference_t<_Base>; |
1944 | |
1945 | _Iterator() requires default_initializable<_Base_iter> = default; |
1946 | |
1947 | constexpr |
1948 | _Iterator(_Parent* __parent, _Base_iter __current) |
1949 | : _M_current(std::move(__current)), |
1950 | _M_parent(__parent) |
1951 | { } |
1952 | |
1953 | constexpr |
1954 | _Iterator(_Iterator<!_Const> __i) |
1955 | requires _Const |
1956 | && convertible_to<iterator_t<_Vp>, _Base_iter> |
1957 | : _M_current(std::move(__i._M_current)), _M_parent(__i._M_parent) |
1958 | { } |
1959 | |
1960 | constexpr const _Base_iter& |
1961 | base() const & noexcept |
1962 | { return _M_current; } |
1963 | |
1964 | constexpr _Base_iter |
1965 | base() && |
1966 | { return std::move(_M_current); } |
1967 | |
1968 | constexpr decltype(auto) |
1969 | operator*() const |
1970 | noexcept(noexcept(std::__invoke(*_M_parent->_M_fun, *_M_current))) |
1971 | { return std::__invoke(*_M_parent->_M_fun, *_M_current); } |
1972 | |
1973 | constexpr _Iterator& |
1974 | operator++() |
1975 | { |
1976 | ++_M_current; |
1977 | return *this; |
1978 | } |
1979 | |
1980 | constexpr void |
1981 | operator++(int) |
1982 | { ++_M_current; } |
1983 | |
1984 | constexpr _Iterator |
1985 | operator++(int) requires forward_range<_Base> |
1986 | { |
1987 | auto __tmp = *this; |
1988 | ++*this; |
1989 | return __tmp; |
1990 | } |
1991 | |
1992 | constexpr _Iterator& |
1993 | operator--() requires bidirectional_range<_Base> |
1994 | { |
1995 | --_M_current; |
1996 | return *this; |
1997 | } |
1998 | |
1999 | constexpr _Iterator |
2000 | operator--(int) requires bidirectional_range<_Base> |
2001 | { |
2002 | auto __tmp = *this; |
2003 | --*this; |
2004 | return __tmp; |
2005 | } |
2006 | |
2007 | constexpr _Iterator& |
2008 | operator+=(difference_type __n) requires random_access_range<_Base> |
2009 | { |
2010 | _M_current += __n; |
2011 | return *this; |
2012 | } |
2013 | |
2014 | constexpr _Iterator& |
2015 | operator-=(difference_type __n) requires random_access_range<_Base> |
2016 | { |
2017 | _M_current -= __n; |
2018 | return *this; |
2019 | } |
2020 | |
2021 | constexpr decltype(auto) |
2022 | operator[](difference_type __n) const |
2023 | requires random_access_range<_Base> |
2024 | { return std::__invoke(*_M_parent->_M_fun, _M_current[__n]); } |
2025 | |
2026 | friend constexpr bool |
2027 | operator==(const _Iterator& __x, const _Iterator& __y) |
2028 | requires equality_comparable<_Base_iter> |
2029 | { return __x._M_current == __y._M_current; } |
2030 | |
2031 | friend constexpr bool |
2032 | operator<(const _Iterator& __x, const _Iterator& __y) |
2033 | requires random_access_range<_Base> |
2034 | { return __x._M_current < __y._M_current; } |
2035 | |
2036 | friend constexpr bool |
2037 | operator>(const _Iterator& __x, const _Iterator& __y) |
2038 | requires random_access_range<_Base> |
2039 | { return __y < __x; } |
2040 | |
2041 | friend constexpr bool |
2042 | operator<=(const _Iterator& __x, const _Iterator& __y) |
2043 | requires random_access_range<_Base> |
2044 | { return !(__y < __x); } |
2045 | |
2046 | friend constexpr bool |
2047 | operator>=(const _Iterator& __x, const _Iterator& __y) |
2048 | requires random_access_range<_Base> |
2049 | { return !(__x < __y); } |
2050 | |
2051 | #ifdef __cpp_lib_three_way_comparison |
2052 | friend constexpr auto |
2053 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
2054 | requires random_access_range<_Base> |
2055 | && three_way_comparable<_Base_iter> |
2056 | { return __x._M_current <=> __y._M_current; } |
2057 | #endif |
2058 | |
2059 | friend constexpr _Iterator |
2060 | operator+(_Iterator __i, difference_type __n) |
2061 | requires random_access_range<_Base> |
2062 | { return {__i._M_parent, __i._M_current + __n}; } |
2063 | |
2064 | friend constexpr _Iterator |
2065 | operator+(difference_type __n, _Iterator __i) |
2066 | requires random_access_range<_Base> |
2067 | { return {__i._M_parent, __i._M_current + __n}; } |
2068 | |
2069 | friend constexpr _Iterator |
2070 | operator-(_Iterator __i, difference_type __n) |
2071 | requires random_access_range<_Base> |
2072 | { return {__i._M_parent, __i._M_current - __n}; } |
2073 | |
2074 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
2075 | // 3483. transform_view::iterator's difference is overconstrained |
2076 | friend constexpr difference_type |
2077 | operator-(const _Iterator& __x, const _Iterator& __y) |
2078 | requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>> |
2079 | { return __x._M_current - __y._M_current; } |
2080 | |
2081 | friend constexpr decltype(auto) |
2082 | iter_move(const _Iterator& __i) noexcept(noexcept(*__i)) |
2083 | { |
2084 | if constexpr (is_lvalue_reference_v<decltype(*__i)>) |
2085 | return std::move(*__i); |
2086 | else |
2087 | return *__i; |
2088 | } |
2089 | |
2090 | friend _Iterator<!_Const>; |
2091 | template<bool> friend struct _Sentinel; |
2092 | }; |
2093 | |
2094 | template<bool _Const> |
2095 | struct _Sentinel |
2096 | { |
2097 | private: |
2098 | using _Parent = __detail::__maybe_const_t<_Const, transform_view>; |
2099 | using _Base = transform_view::_Base<_Const>; |
2100 | |
2101 | template<bool _Const2> |
2102 | constexpr auto |
2103 | __distance_from(const _Iterator<_Const2>& __i) const |
2104 | { return _M_end - __i._M_current; } |
2105 | |
2106 | template<bool _Const2> |
2107 | constexpr bool |
2108 | __equal(const _Iterator<_Const2>& __i) const |
2109 | { return __i._M_current == _M_end; } |
2110 | |
2111 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
2112 | |
2113 | public: |
2114 | _Sentinel() = default; |
2115 | |
2116 | constexpr explicit |
2117 | _Sentinel(sentinel_t<_Base> __end) |
2118 | : _M_end(__end) |
2119 | { } |
2120 | |
2121 | constexpr |
2122 | _Sentinel(_Sentinel<!_Const> __i) |
2123 | requires _Const |
2124 | && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
2125 | : _M_end(std::move(__i._M_end)) |
2126 | { } |
2127 | |
2128 | constexpr sentinel_t<_Base> |
2129 | base() const |
2130 | { return _M_end; } |
2131 | |
2132 | template<bool _Const2> |
2133 | requires sentinel_for<sentinel_t<_Base>, |
2134 | iterator_t<__detail::__maybe_const_t<_Const2, _Vp>>> |
2135 | friend constexpr bool |
2136 | operator==(const _Iterator<_Const2>& __x, const _Sentinel& __y) |
2137 | { return __y.__equal(__x); } |
2138 | |
2139 | template<bool _Const2, |
2140 | typename _Base2 = __detail::__maybe_const_t<_Const2, _Vp>> |
2141 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> |
2142 | friend constexpr range_difference_t<_Base2> |
2143 | operator-(const _Iterator<_Const2>& __x, const _Sentinel& __y) |
2144 | { return -__y.__distance_from(__x); } |
2145 | |
2146 | template<bool _Const2, |
2147 | typename _Base2 = __detail::__maybe_const_t<_Const2, _Vp>> |
2148 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> |
2149 | friend constexpr range_difference_t<_Base2> |
2150 | operator-(const _Sentinel& __y, const _Iterator<_Const2>& __x) |
2151 | { return __y.__distance_from(__x); } |
2152 | |
2153 | friend _Sentinel<!_Const>; |
2154 | }; |
2155 | |
2156 | _Vp _M_base = _Vp(); |
2157 | [[no_unique_address]] __detail::__box<_Fp> _M_fun; |
2158 | |
2159 | public: |
2160 | transform_view() requires (default_initializable<_Vp> |
2161 | && default_initializable<_Fp>) |
2162 | = default; |
2163 | |
2164 | constexpr |
2165 | transform_view(_Vp __base, _Fp __fun) |
2166 | : _M_base(std::move(__base)), _M_fun(std::move(__fun)) |
2167 | { } |
2168 | |
2169 | constexpr _Vp |
2170 | base() const& requires copy_constructible<_Vp> |
2171 | { return _M_base ; } |
2172 | |
2173 | constexpr _Vp |
2174 | base() && |
2175 | { return std::move(_M_base); } |
2176 | |
2177 | constexpr _Iterator<false> |
2178 | begin() |
2179 | { return _Iterator<false>{this, ranges::begin(_M_base)}; } |
2180 | |
2181 | constexpr _Iterator<true> |
2182 | begin() const |
2183 | requires range<const _Vp> |
2184 | && regular_invocable<const _Fp&, range_reference_t<const _Vp>> |
2185 | { return _Iterator<true>{this, ranges::begin(_M_base)}; } |
2186 | |
2187 | constexpr _Sentinel<false> |
2188 | end() |
2189 | { return _Sentinel<false>{ranges::end(_M_base)}; } |
2190 | |
2191 | constexpr _Iterator<false> |
2192 | end() requires common_range<_Vp> |
2193 | { return _Iterator<false>{this, ranges::end(_M_base)}; } |
2194 | |
2195 | constexpr _Sentinel<true> |
2196 | end() const |
2197 | requires range<const _Vp> |
2198 | && regular_invocable<const _Fp&, range_reference_t<const _Vp>> |
2199 | { return _Sentinel<true>{ranges::end(_M_base)}; } |
2200 | |
2201 | constexpr _Iterator<true> |
2202 | end() const |
2203 | requires common_range<const _Vp> |
2204 | && regular_invocable<const _Fp&, range_reference_t<const _Vp>> |
2205 | { return _Iterator<true>{this, ranges::end(_M_base)}; } |
2206 | |
2207 | constexpr auto |
2208 | size() requires sized_range<_Vp> |
2209 | { return ranges::size(_M_base); } |
2210 | |
2211 | constexpr auto |
2212 | size() const requires sized_range<const _Vp> |
2213 | { return ranges::size(_M_base); } |
2214 | }; |
2215 | |
2216 | template<typename _Range, typename _Fp> |
2217 | transform_view(_Range&&, _Fp) -> transform_view<views::all_t<_Range>, _Fp>; |
2218 | |
2219 | namespace views |
2220 | { |
2221 | namespace __detail |
2222 | { |
2223 | template<typename _Range, typename _Fp> |
2224 | concept __can_transform_view |
2225 | = requires { transform_view(std::declval<_Range>(), std::declval<_Fp>()); }; |
2226 | } // namespace __detail |
2227 | |
2228 | struct _Transform : __adaptor::_RangeAdaptor<_Transform> |
2229 | { |
2230 | template<viewable_range _Range, typename _Fp> |
2231 | requires __detail::__can_transform_view<_Range, _Fp> |
2232 | constexpr auto |
2233 | operator() [[nodiscard]] (_Range&& __r, _Fp&& __f) const |
2234 | { |
2235 | return transform_view(std::forward<_Range>(__r), std::forward<_Fp>(__f)); |
2236 | } |
2237 | |
2238 | using _RangeAdaptor<_Transform>::operator(); |
2239 | static constexpr int _S_arity = 2; |
2240 | static constexpr bool = true; |
2241 | }; |
2242 | |
2243 | inline constexpr _Transform transform; |
2244 | } // namespace views |
2245 | |
2246 | template<view _Vp> |
2247 | class take_view : public view_interface<take_view<_Vp>> |
2248 | { |
2249 | private: |
2250 | template<bool _Const> |
2251 | using _CI = counted_iterator< |
2252 | iterator_t<__detail::__maybe_const_t<_Const, _Vp>>>; |
2253 | |
2254 | template<bool _Const> |
2255 | struct _Sentinel |
2256 | { |
2257 | private: |
2258 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
2259 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
2260 | |
2261 | public: |
2262 | _Sentinel() = default; |
2263 | |
2264 | constexpr explicit |
2265 | _Sentinel(sentinel_t<_Base> __end) |
2266 | : _M_end(__end) |
2267 | { } |
2268 | |
2269 | constexpr |
2270 | _Sentinel(_Sentinel<!_Const> __s) |
2271 | requires _Const && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
2272 | : _M_end(std::move(__s._M_end)) |
2273 | { } |
2274 | |
2275 | constexpr sentinel_t<_Base> |
2276 | base() const |
2277 | { return _M_end; } |
2278 | |
2279 | friend constexpr bool |
2280 | operator==(const _CI<_Const>& __y, const _Sentinel& __x) |
2281 | { return __y.count() == 0 || __y.base() == __x._M_end; } |
2282 | |
2283 | template<bool _OtherConst = !_Const, |
2284 | typename _Base2 = __detail::__maybe_const_t<_OtherConst, _Vp>> |
2285 | requires sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> |
2286 | friend constexpr bool |
2287 | operator==(const _CI<_OtherConst>& __y, const _Sentinel& __x) |
2288 | { return __y.count() == 0 || __y.base() == __x._M_end; } |
2289 | |
2290 | friend _Sentinel<!_Const>; |
2291 | }; |
2292 | |
2293 | _Vp _M_base = _Vp(); |
2294 | range_difference_t<_Vp> _M_count = 0; |
2295 | |
2296 | public: |
2297 | take_view() requires default_initializable<_Vp> = default; |
2298 | |
2299 | constexpr |
2300 | take_view(_Vp __base, range_difference_t<_Vp> __count) |
2301 | : _M_base(std::move(__base)), _M_count(std::move(__count)) |
2302 | { } |
2303 | |
2304 | constexpr _Vp |
2305 | base() const& requires copy_constructible<_Vp> |
2306 | { return _M_base; } |
2307 | |
2308 | constexpr _Vp |
2309 | base() && |
2310 | { return std::move(_M_base); } |
2311 | |
2312 | constexpr auto |
2313 | begin() requires (!__detail::__simple_view<_Vp>) |
2314 | { |
2315 | if constexpr (sized_range<_Vp>) |
2316 | { |
2317 | if constexpr (random_access_range<_Vp>) |
2318 | return ranges::begin(_M_base); |
2319 | else |
2320 | { |
2321 | auto __sz = size(); |
2322 | return counted_iterator(ranges::begin(_M_base), __sz); |
2323 | } |
2324 | } |
2325 | else |
2326 | return counted_iterator(ranges::begin(_M_base), _M_count); |
2327 | } |
2328 | |
2329 | constexpr auto |
2330 | begin() const requires range<const _Vp> |
2331 | { |
2332 | if constexpr (sized_range<const _Vp>) |
2333 | { |
2334 | if constexpr (random_access_range<const _Vp>) |
2335 | return ranges::begin(_M_base); |
2336 | else |
2337 | { |
2338 | auto __sz = size(); |
2339 | return counted_iterator(ranges::begin(_M_base), __sz); |
2340 | } |
2341 | } |
2342 | else |
2343 | return counted_iterator(ranges::begin(_M_base), _M_count); |
2344 | } |
2345 | |
2346 | constexpr auto |
2347 | end() requires (!__detail::__simple_view<_Vp>) |
2348 | { |
2349 | if constexpr (sized_range<_Vp>) |
2350 | { |
2351 | if constexpr (random_access_range<_Vp>) |
2352 | return ranges::begin(_M_base) + size(); |
2353 | else |
2354 | return default_sentinel; |
2355 | } |
2356 | else |
2357 | return _Sentinel<false>{ranges::end(_M_base)}; |
2358 | } |
2359 | |
2360 | constexpr auto |
2361 | end() const requires range<const _Vp> |
2362 | { |
2363 | if constexpr (sized_range<const _Vp>) |
2364 | { |
2365 | if constexpr (random_access_range<const _Vp>) |
2366 | return ranges::begin(_M_base) + size(); |
2367 | else |
2368 | return default_sentinel; |
2369 | } |
2370 | else |
2371 | return _Sentinel<true>{ranges::end(_M_base)}; |
2372 | } |
2373 | |
2374 | constexpr auto |
2375 | size() requires sized_range<_Vp> |
2376 | { |
2377 | auto __n = ranges::size(_M_base); |
2378 | return std::min(__n, static_cast<decltype(__n)>(_M_count)); |
2379 | } |
2380 | |
2381 | constexpr auto |
2382 | size() const requires sized_range<const _Vp> |
2383 | { |
2384 | auto __n = ranges::size(_M_base); |
2385 | return std::min(__n, static_cast<decltype(__n)>(_M_count)); |
2386 | } |
2387 | }; |
2388 | |
2389 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
2390 | // 3447. Deduction guides for take_view and drop_view have different |
2391 | // constraints |
2392 | template<typename _Range> |
2393 | take_view(_Range&&, range_difference_t<_Range>) |
2394 | -> take_view<views::all_t<_Range>>; |
2395 | |
2396 | template<typename _Tp> |
2397 | inline constexpr bool enable_borrowed_range<take_view<_Tp>> |
2398 | = enable_borrowed_range<_Tp>; |
2399 | |
2400 | namespace views |
2401 | { |
2402 | namespace __detail |
2403 | { |
2404 | template<typename _Range> |
2405 | inline constexpr bool __is_empty_view = false; |
2406 | |
2407 | template<typename _Tp> |
2408 | inline constexpr bool __is_empty_view<empty_view<_Tp>> = true; |
2409 | |
2410 | template<typename _Range> |
2411 | inline constexpr bool __is_basic_string_view = false; |
2412 | |
2413 | template<typename _CharT, typename _Traits> |
2414 | inline constexpr bool __is_basic_string_view<basic_string_view<_CharT, _Traits>> |
2415 | = true; |
2416 | |
2417 | using ranges::__detail::__is_subrange; |
2418 | |
2419 | template<typename _Range> |
2420 | inline constexpr bool __is_iota_view = false; |
2421 | |
2422 | template<typename _Winc, typename _Bound> |
2423 | inline constexpr bool __is_iota_view<iota_view<_Winc, _Bound>> = true; |
2424 | |
2425 | template<typename _Range> |
2426 | inline constexpr bool __is_repeat_view = false; |
2427 | |
2428 | template<typename _Range> |
2429 | constexpr auto |
2430 | __take_of_repeat_view(_Range&&, range_difference_t<_Range>); // defined later |
2431 | |
2432 | template<typename _Range, typename _Dp> |
2433 | concept __can_take_view |
2434 | = requires { take_view(std::declval<_Range>(), std::declval<_Dp>()); }; |
2435 | } // namespace __detail |
2436 | |
2437 | struct _Take : __adaptor::_RangeAdaptor<_Take> |
2438 | { |
2439 | template<viewable_range _Range, typename _Dp = range_difference_t<_Range>> |
2440 | requires __detail::__can_take_view<_Range, _Dp> |
2441 | constexpr auto |
2442 | operator() [[nodiscard]] (_Range&& __r, type_identity_t<_Dp> __n) const |
2443 | { |
2444 | using _Tp = remove_cvref_t<_Range>; |
2445 | if constexpr (__detail::__is_empty_view<_Tp>) |
2446 | return _Tp(); |
2447 | else if constexpr (random_access_range<_Tp> |
2448 | && sized_range<_Tp> |
2449 | && (std::__detail::__is_span<_Tp> |
2450 | || __detail::__is_basic_string_view<_Tp> |
2451 | || __detail::__is_subrange<_Tp> |
2452 | || __detail::__is_iota_view<_Tp>)) |
2453 | { |
2454 | __n = std::min<_Dp>(ranges::distance(__r), __n); |
2455 | auto __begin = ranges::begin(__r); |
2456 | auto __end = __begin + __n; |
2457 | if constexpr (std::__detail::__is_span<_Tp>) |
2458 | return span<typename _Tp::element_type>(__begin, __end); |
2459 | else if constexpr (__detail::__is_basic_string_view<_Tp>) |
2460 | return _Tp(__begin, __end); |
2461 | else if constexpr (__detail::__is_subrange<_Tp>) |
2462 | return subrange<iterator_t<_Tp>>(__begin, __end); |
2463 | else |
2464 | return iota_view(*__begin, *__end); |
2465 | } |
2466 | else if constexpr (__detail::__is_repeat_view<_Tp>) |
2467 | return __detail::__take_of_repeat_view(std::forward<_Range>(__r), __n); |
2468 | else |
2469 | return take_view(std::forward<_Range>(__r), __n); |
2470 | } |
2471 | |
2472 | using _RangeAdaptor<_Take>::operator(); |
2473 | static constexpr int _S_arity = 2; |
2474 | // The count argument of views::take is not always simple -- it can be |
2475 | // e.g. a move-only class that's implicitly convertible to the difference |
2476 | // type. But an integer-like count argument is surely simple. |
2477 | template<typename _Tp> |
2478 | static constexpr bool |
2479 | = ranges::__detail::__is_integer_like<_Tp>; |
2480 | }; |
2481 | |
2482 | inline constexpr _Take take; |
2483 | } // namespace views |
2484 | |
2485 | template<view _Vp, typename _Pred> |
2486 | requires input_range<_Vp> && is_object_v<_Pred> |
2487 | && indirect_unary_predicate<const _Pred, iterator_t<_Vp>> |
2488 | class take_while_view : public view_interface<take_while_view<_Vp, _Pred>> |
2489 | { |
2490 | template<bool _Const> |
2491 | struct _Sentinel |
2492 | { |
2493 | private: |
2494 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
2495 | |
2496 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
2497 | const _Pred* _M_pred = nullptr; |
2498 | |
2499 | public: |
2500 | _Sentinel() = default; |
2501 | |
2502 | constexpr explicit |
2503 | _Sentinel(sentinel_t<_Base> __end, const _Pred* __pred) |
2504 | : _M_end(__end), _M_pred(__pred) |
2505 | { } |
2506 | |
2507 | constexpr |
2508 | _Sentinel(_Sentinel<!_Const> __s) |
2509 | requires _Const && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
2510 | : _M_end(__s._M_end), _M_pred(__s._M_pred) |
2511 | { } |
2512 | |
2513 | constexpr sentinel_t<_Base> |
2514 | base() const { return _M_end; } |
2515 | |
2516 | friend constexpr bool |
2517 | operator==(const iterator_t<_Base>& __x, const _Sentinel& __y) |
2518 | { return __y._M_end == __x || !std::__invoke(*__y._M_pred, *__x); } |
2519 | |
2520 | template<bool _OtherConst = !_Const, |
2521 | typename _Base2 = __detail::__maybe_const_t<_OtherConst, _Vp>> |
2522 | requires sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> |
2523 | friend constexpr bool |
2524 | operator==(const iterator_t<_Base2>& __x, const _Sentinel& __y) |
2525 | { return __y._M_end == __x || !std::__invoke(*__y._M_pred, *__x); } |
2526 | |
2527 | friend _Sentinel<!_Const>; |
2528 | }; |
2529 | |
2530 | _Vp _M_base = _Vp(); |
2531 | [[no_unique_address]] __detail::__box<_Pred> _M_pred; |
2532 | |
2533 | public: |
2534 | take_while_view() requires (default_initializable<_Vp> |
2535 | && default_initializable<_Pred>) |
2536 | = default; |
2537 | |
2538 | constexpr |
2539 | take_while_view(_Vp __base, _Pred __pred) |
2540 | : _M_base(std::move(__base)), _M_pred(std::move(__pred)) |
2541 | { } |
2542 | |
2543 | constexpr _Vp |
2544 | base() const& requires copy_constructible<_Vp> |
2545 | { return _M_base; } |
2546 | |
2547 | constexpr _Vp |
2548 | base() && |
2549 | { return std::move(_M_base); } |
2550 | |
2551 | constexpr const _Pred& |
2552 | pred() const |
2553 | { return *_M_pred; } |
2554 | |
2555 | constexpr auto |
2556 | begin() requires (!__detail::__simple_view<_Vp>) |
2557 | { return ranges::begin(_M_base); } |
2558 | |
2559 | constexpr auto |
2560 | begin() const requires range<const _Vp> |
2561 | && indirect_unary_predicate<const _Pred, iterator_t<const _Vp>> |
2562 | { return ranges::begin(_M_base); } |
2563 | |
2564 | constexpr auto |
2565 | end() requires (!__detail::__simple_view<_Vp>) |
2566 | { return _Sentinel<false>(ranges::end(_M_base), |
2567 | std::__addressof(*_M_pred)); } |
2568 | |
2569 | constexpr auto |
2570 | end() const requires range<const _Vp> |
2571 | && indirect_unary_predicate<const _Pred, iterator_t<const _Vp>> |
2572 | { return _Sentinel<true>(ranges::end(_M_base), |
2573 | std::__addressof(*_M_pred)); } |
2574 | }; |
2575 | |
2576 | template<typename _Range, typename _Pred> |
2577 | take_while_view(_Range&&, _Pred) |
2578 | -> take_while_view<views::all_t<_Range>, _Pred>; |
2579 | |
2580 | namespace views |
2581 | { |
2582 | namespace __detail |
2583 | { |
2584 | template<typename _Range, typename _Pred> |
2585 | concept __can_take_while_view |
2586 | = requires { take_while_view(std::declval<_Range>(), std::declval<_Pred>()); }; |
2587 | } // namespace __detail |
2588 | |
2589 | struct _TakeWhile : __adaptor::_RangeAdaptor<_TakeWhile> |
2590 | { |
2591 | template<viewable_range _Range, typename _Pred> |
2592 | requires __detail::__can_take_while_view<_Range, _Pred> |
2593 | constexpr auto |
2594 | operator() [[nodiscard]] (_Range&& __r, _Pred&& __p) const |
2595 | { |
2596 | return take_while_view(std::forward<_Range>(__r), std::forward<_Pred>(__p)); |
2597 | } |
2598 | |
2599 | using _RangeAdaptor<_TakeWhile>::operator(); |
2600 | static constexpr int _S_arity = 2; |
2601 | static constexpr bool = true; |
2602 | }; |
2603 | |
2604 | inline constexpr _TakeWhile take_while; |
2605 | } // namespace views |
2606 | |
2607 | template<view _Vp> |
2608 | class drop_view : public view_interface<drop_view<_Vp>> |
2609 | { |
2610 | private: |
2611 | _Vp _M_base = _Vp(); |
2612 | range_difference_t<_Vp> _M_count = 0; |
2613 | |
2614 | // ranges::next(begin(base), count, end(base)) is O(1) if _Vp satisfies |
2615 | // both random_access_range and sized_range. Otherwise, cache its result. |
2616 | static constexpr bool _S_needs_cached_begin |
2617 | = !(random_access_range<const _Vp> && sized_range<const _Vp>); |
2618 | [[no_unique_address]] |
2619 | __detail::__maybe_present_t<_S_needs_cached_begin, |
2620 | __detail::_CachedPosition<_Vp>> |
2621 | _M_cached_begin; |
2622 | |
2623 | public: |
2624 | drop_view() requires default_initializable<_Vp> = default; |
2625 | |
2626 | constexpr |
2627 | drop_view(_Vp __base, range_difference_t<_Vp> __count) |
2628 | : _M_base(std::move(__base)), _M_count(__count) |
2629 | { __glibcxx_assert(__count >= 0); } |
2630 | |
2631 | constexpr _Vp |
2632 | base() const& requires copy_constructible<_Vp> |
2633 | { return _M_base; } |
2634 | |
2635 | constexpr _Vp |
2636 | base() && |
2637 | { return std::move(_M_base); } |
2638 | |
2639 | // This overload is disabled for simple views with constant-time begin(). |
2640 | constexpr auto |
2641 | begin() |
2642 | requires (!(__detail::__simple_view<_Vp> |
2643 | && random_access_range<const _Vp> |
2644 | && sized_range<const _Vp>)) |
2645 | { |
2646 | if constexpr (_S_needs_cached_begin) |
2647 | if (_M_cached_begin._M_has_value()) |
2648 | return _M_cached_begin._M_get(_M_base); |
2649 | |
2650 | auto __it = ranges::next(ranges::begin(_M_base), |
2651 | _M_count, ranges::end(_M_base)); |
2652 | if constexpr (_S_needs_cached_begin) |
2653 | _M_cached_begin._M_set(_M_base, __it); |
2654 | return __it; |
2655 | } |
2656 | |
2657 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
2658 | // 3482. drop_view's const begin should additionally require sized_range |
2659 | constexpr auto |
2660 | begin() const |
2661 | requires random_access_range<const _Vp> && sized_range<const _Vp> |
2662 | { |
2663 | return ranges::begin(_M_base) + ranges::min(ranges::distance(_M_base), |
2664 | _M_count); |
2665 | } |
2666 | |
2667 | constexpr auto |
2668 | end() requires (!__detail::__simple_view<_Vp>) |
2669 | { return ranges::end(_M_base); } |
2670 | |
2671 | constexpr auto |
2672 | end() const requires range<const _Vp> |
2673 | { return ranges::end(_M_base); } |
2674 | |
2675 | constexpr auto |
2676 | size() requires sized_range<_Vp> |
2677 | { |
2678 | const auto __s = ranges::size(_M_base); |
2679 | const auto __c = static_cast<decltype(__s)>(_M_count); |
2680 | return __s < __c ? 0 : __s - __c; |
2681 | } |
2682 | |
2683 | constexpr auto |
2684 | size() const requires sized_range<const _Vp> |
2685 | { |
2686 | const auto __s = ranges::size(_M_base); |
2687 | const auto __c = static_cast<decltype(__s)>(_M_count); |
2688 | return __s < __c ? 0 : __s - __c; |
2689 | } |
2690 | }; |
2691 | |
2692 | template<typename _Range> |
2693 | drop_view(_Range&&, range_difference_t<_Range>) |
2694 | -> drop_view<views::all_t<_Range>>; |
2695 | |
2696 | template<typename _Tp> |
2697 | inline constexpr bool enable_borrowed_range<drop_view<_Tp>> |
2698 | = enable_borrowed_range<_Tp>; |
2699 | |
2700 | namespace views |
2701 | { |
2702 | namespace __detail |
2703 | { |
2704 | template<typename _Range> |
2705 | constexpr auto |
2706 | __drop_of_repeat_view(_Range&&, range_difference_t<_Range>); // defined later |
2707 | |
2708 | template<typename _Range, typename _Dp> |
2709 | concept __can_drop_view |
2710 | = requires { drop_view(std::declval<_Range>(), std::declval<_Dp>()); }; |
2711 | } // namespace __detail |
2712 | |
2713 | struct _Drop : __adaptor::_RangeAdaptor<_Drop> |
2714 | { |
2715 | template<viewable_range _Range, typename _Dp = range_difference_t<_Range>> |
2716 | requires __detail::__can_drop_view<_Range, _Dp> |
2717 | constexpr auto |
2718 | operator() [[nodiscard]] (_Range&& __r, type_identity_t<_Dp> __n) const |
2719 | { |
2720 | using _Tp = remove_cvref_t<_Range>; |
2721 | if constexpr (__detail::__is_empty_view<_Tp>) |
2722 | return _Tp(); |
2723 | else if constexpr (random_access_range<_Tp> |
2724 | && sized_range<_Tp> |
2725 | && (std::__detail::__is_span<_Tp> |
2726 | || __detail::__is_basic_string_view<_Tp> |
2727 | || __detail::__is_iota_view<_Tp> |
2728 | || __detail::__is_subrange<_Tp>)) |
2729 | { |
2730 | __n = std::min<_Dp>(ranges::distance(__r), __n); |
2731 | auto __begin = ranges::begin(__r) + __n; |
2732 | auto __end = ranges::end(__r); |
2733 | if constexpr (std::__detail::__is_span<_Tp>) |
2734 | return span<typename _Tp::element_type>(__begin, __end); |
2735 | else if constexpr (__detail::__is_subrange<_Tp>) |
2736 | { |
2737 | if constexpr (_Tp::_S_store_size) |
2738 | { |
2739 | using ranges::__detail::__to_unsigned_like; |
2740 | auto __m = ranges::distance(__r) - __n; |
2741 | return _Tp(__begin, __end, __to_unsigned_like(__m)); |
2742 | } |
2743 | else |
2744 | return _Tp(__begin, __end); |
2745 | } |
2746 | else |
2747 | return _Tp(__begin, __end); |
2748 | } |
2749 | else if constexpr (__detail::__is_repeat_view<_Tp>) |
2750 | return __detail::__drop_of_repeat_view(std::forward<_Range>(__r), __n); |
2751 | else |
2752 | return drop_view(std::forward<_Range>(__r), __n); |
2753 | } |
2754 | |
2755 | using _RangeAdaptor<_Drop>::operator(); |
2756 | static constexpr int _S_arity = 2; |
2757 | template<typename _Tp> |
2758 | static constexpr bool |
2759 | = _Take::_S_has_simple_extra_args<_Tp>; |
2760 | }; |
2761 | |
2762 | inline constexpr _Drop drop; |
2763 | } // namespace views |
2764 | |
2765 | template<view _Vp, typename _Pred> |
2766 | requires input_range<_Vp> && is_object_v<_Pred> |
2767 | && indirect_unary_predicate<const _Pred, iterator_t<_Vp>> |
2768 | class drop_while_view : public view_interface<drop_while_view<_Vp, _Pred>> |
2769 | { |
2770 | private: |
2771 | _Vp _M_base = _Vp(); |
2772 | [[no_unique_address]] __detail::__box<_Pred> _M_pred; |
2773 | [[no_unique_address]] __detail::_CachedPosition<_Vp> _M_cached_begin; |
2774 | |
2775 | public: |
2776 | drop_while_view() requires (default_initializable<_Vp> |
2777 | && default_initializable<_Pred>) |
2778 | = default; |
2779 | |
2780 | constexpr |
2781 | drop_while_view(_Vp __base, _Pred __pred) |
2782 | : _M_base(std::move(__base)), _M_pred(std::move(__pred)) |
2783 | { } |
2784 | |
2785 | constexpr _Vp |
2786 | base() const& requires copy_constructible<_Vp> |
2787 | { return _M_base; } |
2788 | |
2789 | constexpr _Vp |
2790 | base() && |
2791 | { return std::move(_M_base); } |
2792 | |
2793 | constexpr const _Pred& |
2794 | pred() const |
2795 | { return *_M_pred; } |
2796 | |
2797 | constexpr auto |
2798 | begin() |
2799 | { |
2800 | if (_M_cached_begin._M_has_value()) |
2801 | return _M_cached_begin._M_get(_M_base); |
2802 | |
2803 | __glibcxx_assert(_M_pred.has_value()); |
2804 | auto __it = ranges::find_if_not(ranges::begin(_M_base), |
2805 | ranges::end(_M_base), |
2806 | std::cref(*_M_pred)); |
2807 | _M_cached_begin._M_set(_M_base, __it); |
2808 | return __it; |
2809 | } |
2810 | |
2811 | constexpr auto |
2812 | end() |
2813 | { return ranges::end(_M_base); } |
2814 | }; |
2815 | |
2816 | template<typename _Range, typename _Pred> |
2817 | drop_while_view(_Range&&, _Pred) |
2818 | -> drop_while_view<views::all_t<_Range>, _Pred>; |
2819 | |
2820 | template<typename _Tp, typename _Pred> |
2821 | inline constexpr bool enable_borrowed_range<drop_while_view<_Tp, _Pred>> |
2822 | = enable_borrowed_range<_Tp>; |
2823 | |
2824 | namespace views |
2825 | { |
2826 | namespace __detail |
2827 | { |
2828 | template<typename _Range, typename _Pred> |
2829 | concept __can_drop_while_view |
2830 | = requires { drop_while_view(std::declval<_Range>(), std::declval<_Pred>()); }; |
2831 | } // namespace __detail |
2832 | |
2833 | struct _DropWhile : __adaptor::_RangeAdaptor<_DropWhile> |
2834 | { |
2835 | template<viewable_range _Range, typename _Pred> |
2836 | requires __detail::__can_drop_while_view<_Range, _Pred> |
2837 | constexpr auto |
2838 | operator() [[nodiscard]] (_Range&& __r, _Pred&& __p) const |
2839 | { |
2840 | return drop_while_view(std::forward<_Range>(__r), |
2841 | std::forward<_Pred>(__p)); |
2842 | } |
2843 | |
2844 | using _RangeAdaptor<_DropWhile>::operator(); |
2845 | static constexpr int _S_arity = 2; |
2846 | static constexpr bool = true; |
2847 | }; |
2848 | |
2849 | inline constexpr _DropWhile drop_while; |
2850 | } // namespace views |
2851 | |
2852 | namespace __detail |
2853 | { |
2854 | template<typename _Tp> |
2855 | constexpr _Tp& |
2856 | __as_lvalue(_Tp&& __t) |
2857 | { return static_cast<_Tp&>(__t); } |
2858 | } // namespace __detail |
2859 | |
2860 | template<input_range _Vp> |
2861 | requires view<_Vp> && input_range<range_reference_t<_Vp>> |
2862 | class join_view : public view_interface<join_view<_Vp>> |
2863 | { |
2864 | private: |
2865 | using _InnerRange = range_reference_t<_Vp>; |
2866 | |
2867 | template<bool _Const> |
2868 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
2869 | |
2870 | template<bool _Const> |
2871 | using _Outer_iter = iterator_t<_Base<_Const>>; |
2872 | |
2873 | template<bool _Const> |
2874 | using _Inner_iter = iterator_t<range_reference_t<_Base<_Const>>>; |
2875 | |
2876 | template<bool _Const> |
2877 | static constexpr bool _S_ref_is_glvalue |
2878 | = is_reference_v<range_reference_t<_Base<_Const>>>; |
2879 | |
2880 | template<bool _Const> |
2881 | struct __iter_cat |
2882 | { }; |
2883 | |
2884 | template<bool _Const> |
2885 | requires _S_ref_is_glvalue<_Const> |
2886 | && forward_range<_Base<_Const>> |
2887 | && forward_range<range_reference_t<_Base<_Const>>> |
2888 | struct __iter_cat<_Const> |
2889 | { |
2890 | private: |
2891 | static constexpr auto |
2892 | _S_iter_cat() |
2893 | { |
2894 | using _Outer_iter = join_view::_Outer_iter<_Const>; |
2895 | using _Inner_iter = join_view::_Inner_iter<_Const>; |
2896 | using _OuterCat = typename iterator_traits<_Outer_iter>::iterator_category; |
2897 | using _InnerCat = typename iterator_traits<_Inner_iter>::iterator_category; |
2898 | if constexpr (derived_from<_OuterCat, bidirectional_iterator_tag> |
2899 | && derived_from<_InnerCat, bidirectional_iterator_tag> |
2900 | && common_range<range_reference_t<_Base<_Const>>>) |
2901 | return bidirectional_iterator_tag{}; |
2902 | else if constexpr (derived_from<_OuterCat, forward_iterator_tag> |
2903 | && derived_from<_InnerCat, forward_iterator_tag>) |
2904 | return forward_iterator_tag{}; |
2905 | else |
2906 | return input_iterator_tag{}; |
2907 | } |
2908 | public: |
2909 | using iterator_category = decltype(_S_iter_cat()); |
2910 | }; |
2911 | |
2912 | template<bool _Const> |
2913 | struct _Sentinel; |
2914 | |
2915 | template<bool _Const> |
2916 | struct _Iterator : __iter_cat<_Const> |
2917 | { |
2918 | private: |
2919 | using _Parent = __detail::__maybe_const_t<_Const, join_view>; |
2920 | using _Base = join_view::_Base<_Const>; |
2921 | |
2922 | friend join_view; |
2923 | |
2924 | static constexpr bool _S_ref_is_glvalue |
2925 | = join_view::_S_ref_is_glvalue<_Const>; |
2926 | |
2927 | constexpr void |
2928 | _M_satisfy() |
2929 | { |
2930 | auto __update_inner = [this] (const iterator_t<_Base>& __x) -> auto&& { |
2931 | if constexpr (_S_ref_is_glvalue) |
2932 | return *__x; |
2933 | else |
2934 | return _M_parent->_M_inner._M_emplace_deref(__x); |
2935 | }; |
2936 | |
2937 | _Outer_iter& __outer = _M_get_outer(); |
2938 | for (; __outer != ranges::end(_M_parent->_M_base); ++__outer) |
2939 | { |
2940 | auto&& __inner = __update_inner(__outer); |
2941 | _M_inner = ranges::begin(__inner); |
2942 | if (_M_inner != ranges::end(__inner)) |
2943 | return; |
2944 | } |
2945 | |
2946 | if constexpr (_S_ref_is_glvalue) |
2947 | _M_inner.reset(); |
2948 | } |
2949 | |
2950 | static constexpr auto |
2951 | _S_iter_concept() |
2952 | { |
2953 | if constexpr (_S_ref_is_glvalue |
2954 | && bidirectional_range<_Base> |
2955 | && bidirectional_range<range_reference_t<_Base>> |
2956 | && common_range<range_reference_t<_Base>>) |
2957 | return bidirectional_iterator_tag{}; |
2958 | else if constexpr (_S_ref_is_glvalue |
2959 | && forward_range<_Base> |
2960 | && forward_range<range_reference_t<_Base>>) |
2961 | return forward_iterator_tag{}; |
2962 | else |
2963 | return input_iterator_tag{}; |
2964 | } |
2965 | |
2966 | using _Outer_iter = join_view::_Outer_iter<_Const>; |
2967 | using _Inner_iter = join_view::_Inner_iter<_Const>; |
2968 | |
2969 | constexpr _Outer_iter& |
2970 | _M_get_outer() |
2971 | { |
2972 | if constexpr (forward_range<_Base>) |
2973 | return _M_outer; |
2974 | else |
2975 | return *_M_parent->_M_outer; |
2976 | } |
2977 | |
2978 | constexpr const _Outer_iter& |
2979 | _M_get_outer() const |
2980 | { |
2981 | if constexpr (forward_range<_Base>) |
2982 | return _M_outer; |
2983 | else |
2984 | return *_M_parent->_M_outer; |
2985 | } |
2986 | |
2987 | constexpr |
2988 | _Iterator(_Parent* __parent, _Outer_iter __outer) requires forward_range<_Base> |
2989 | : _M_outer(std::move(__outer)), _M_parent(__parent) |
2990 | { _M_satisfy(); } |
2991 | |
2992 | constexpr explicit |
2993 | _Iterator(_Parent* __parent) requires (!forward_range<_Base>) |
2994 | : _M_parent(__parent) |
2995 | { _M_satisfy(); } |
2996 | |
2997 | [[no_unique_address]] |
2998 | __detail::__maybe_present_t<forward_range<_Base>, _Outer_iter> _M_outer; |
2999 | optional<_Inner_iter> _M_inner; |
3000 | _Parent* _M_parent = nullptr; |
3001 | |
3002 | public: |
3003 | using iterator_concept = decltype(_S_iter_concept()); |
3004 | // iterator_category defined in __join_view_iter_cat |
3005 | using value_type = range_value_t<range_reference_t<_Base>>; |
3006 | using difference_type |
3007 | = common_type_t<range_difference_t<_Base>, |
3008 | range_difference_t<range_reference_t<_Base>>>; |
3009 | |
3010 | _Iterator() = default; |
3011 | |
3012 | constexpr |
3013 | _Iterator(_Iterator<!_Const> __i) |
3014 | requires _Const |
3015 | && convertible_to<iterator_t<_Vp>, _Outer_iter> |
3016 | && convertible_to<iterator_t<_InnerRange>, _Inner_iter> |
3017 | : _M_outer(std::move(__i._M_outer)), _M_inner(std::move(__i._M_inner)), |
3018 | _M_parent(__i._M_parent) |
3019 | { } |
3020 | |
3021 | constexpr decltype(auto) |
3022 | operator*() const |
3023 | { return **_M_inner; } |
3024 | |
3025 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
3026 | // 3500. join_view::iterator::operator->() is bogus |
3027 | constexpr _Inner_iter |
3028 | operator->() const |
3029 | requires __detail::__has_arrow<_Inner_iter> |
3030 | && copyable<_Inner_iter> |
3031 | { return *_M_inner; } |
3032 | |
3033 | constexpr _Iterator& |
3034 | operator++() |
3035 | { |
3036 | auto&& __inner_range = [this] () -> auto&& { |
3037 | if constexpr (_S_ref_is_glvalue) |
3038 | return *_M_get_outer(); |
3039 | else |
3040 | return *_M_parent->_M_inner; |
3041 | }(); |
3042 | if (++*_M_inner == ranges::end(__inner_range)) |
3043 | { |
3044 | ++_M_get_outer(); |
3045 | _M_satisfy(); |
3046 | } |
3047 | return *this; |
3048 | } |
3049 | |
3050 | constexpr void |
3051 | operator++(int) |
3052 | { ++*this; } |
3053 | |
3054 | constexpr _Iterator |
3055 | operator++(int) |
3056 | requires _S_ref_is_glvalue && forward_range<_Base> |
3057 | && forward_range<range_reference_t<_Base>> |
3058 | { |
3059 | auto __tmp = *this; |
3060 | ++*this; |
3061 | return __tmp; |
3062 | } |
3063 | |
3064 | constexpr _Iterator& |
3065 | operator--() |
3066 | requires _S_ref_is_glvalue && bidirectional_range<_Base> |
3067 | && bidirectional_range<range_reference_t<_Base>> |
3068 | && common_range<range_reference_t<_Base>> |
3069 | { |
3070 | if (_M_outer == ranges::end(_M_parent->_M_base)) |
3071 | _M_inner = ranges::end(__detail::__as_lvalue(*--_M_outer)); |
3072 | while (*_M_inner == ranges::begin(__detail::__as_lvalue(*_M_outer))) |
3073 | *_M_inner = ranges::end(__detail::__as_lvalue(*--_M_outer)); |
3074 | --*_M_inner; |
3075 | return *this; |
3076 | } |
3077 | |
3078 | constexpr _Iterator |
3079 | operator--(int) |
3080 | requires _S_ref_is_glvalue && bidirectional_range<_Base> |
3081 | && bidirectional_range<range_reference_t<_Base>> |
3082 | && common_range<range_reference_t<_Base>> |
3083 | { |
3084 | auto __tmp = *this; |
3085 | --*this; |
3086 | return __tmp; |
3087 | } |
3088 | |
3089 | friend constexpr bool |
3090 | operator==(const _Iterator& __x, const _Iterator& __y) |
3091 | requires _S_ref_is_glvalue |
3092 | && forward_range<_Base> |
3093 | && equality_comparable<_Inner_iter> |
3094 | { |
3095 | return (__x._M_outer == __y._M_outer |
3096 | && __x._M_inner == __y._M_inner); |
3097 | } |
3098 | |
3099 | friend constexpr decltype(auto) |
3100 | iter_move(const _Iterator& __i) |
3101 | noexcept(noexcept(ranges::iter_move(*__i._M_inner))) |
3102 | { return ranges::iter_move(*__i._M_inner); } |
3103 | |
3104 | friend constexpr void |
3105 | iter_swap(const _Iterator& __x, const _Iterator& __y) |
3106 | noexcept(noexcept(ranges::iter_swap(*__x._M_inner, *__y._M_inner))) |
3107 | requires indirectly_swappable<_Inner_iter> |
3108 | { return ranges::iter_swap(*__x._M_inner, *__y._M_inner); } |
3109 | |
3110 | friend _Iterator<!_Const>; |
3111 | template<bool> friend struct _Sentinel; |
3112 | }; |
3113 | |
3114 | template<bool _Const> |
3115 | struct _Sentinel |
3116 | { |
3117 | private: |
3118 | using _Parent = __detail::__maybe_const_t<_Const, join_view>; |
3119 | using _Base = join_view::_Base<_Const>; |
3120 | |
3121 | template<bool _Const2> |
3122 | constexpr bool |
3123 | __equal(const _Iterator<_Const2>& __i) const |
3124 | { return __i._M_get_outer() == _M_end; } |
3125 | |
3126 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
3127 | |
3128 | public: |
3129 | _Sentinel() = default; |
3130 | |
3131 | constexpr explicit |
3132 | _Sentinel(_Parent* __parent) |
3133 | : _M_end(ranges::end(__parent->_M_base)) |
3134 | { } |
3135 | |
3136 | constexpr |
3137 | _Sentinel(_Sentinel<!_Const> __s) |
3138 | requires _Const && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
3139 | : _M_end(std::move(__s._M_end)) |
3140 | { } |
3141 | |
3142 | template<bool _Const2> |
3143 | requires sentinel_for<sentinel_t<_Base>, |
3144 | iterator_t<__detail::__maybe_const_t<_Const2, _Vp>>> |
3145 | friend constexpr bool |
3146 | operator==(const _Iterator<_Const2>& __x, const _Sentinel& __y) |
3147 | { return __y.__equal(__x); } |
3148 | |
3149 | friend _Sentinel<!_Const>; |
3150 | }; |
3151 | |
3152 | _Vp _M_base = _Vp(); |
3153 | [[no_unique_address]] |
3154 | __detail::__maybe_present_t<!forward_range<_Vp>, |
3155 | __detail::__non_propagating_cache<iterator_t<_Vp>>> _M_outer; |
3156 | [[no_unique_address]] |
3157 | __detail::__non_propagating_cache<remove_cv_t<_InnerRange>> _M_inner; |
3158 | |
3159 | public: |
3160 | join_view() requires default_initializable<_Vp> = default; |
3161 | |
3162 | constexpr explicit |
3163 | join_view(_Vp __base) |
3164 | : _M_base(std::move(__base)) |
3165 | { } |
3166 | |
3167 | constexpr _Vp |
3168 | base() const& requires copy_constructible<_Vp> |
3169 | { return _M_base; } |
3170 | |
3171 | constexpr _Vp |
3172 | base() && |
3173 | { return std::move(_M_base); } |
3174 | |
3175 | constexpr auto |
3176 | begin() |
3177 | { |
3178 | if constexpr (forward_range<_Vp>) |
3179 | { |
3180 | constexpr bool __use_const |
3181 | = (__detail::__simple_view<_Vp> |
3182 | && is_reference_v<range_reference_t<_Vp>>); |
3183 | return _Iterator<__use_const>{this, ranges::begin(_M_base)}; |
3184 | } |
3185 | else |
3186 | { |
3187 | _M_outer = ranges::begin(_M_base); |
3188 | return _Iterator<false>{this}; |
3189 | } |
3190 | } |
3191 | |
3192 | constexpr auto |
3193 | begin() const |
3194 | requires forward_range<const _Vp> |
3195 | && is_reference_v<range_reference_t<const _Vp>> |
3196 | && input_range<range_reference_t<const _Vp>> |
3197 | { |
3198 | return _Iterator<true>{this, ranges::begin(_M_base)}; |
3199 | } |
3200 | |
3201 | constexpr auto |
3202 | end() |
3203 | { |
3204 | if constexpr (forward_range<_Vp> && is_reference_v<_InnerRange> |
3205 | && forward_range<_InnerRange> |
3206 | && common_range<_Vp> && common_range<_InnerRange>) |
3207 | return _Iterator<__detail::__simple_view<_Vp>>{this, |
3208 | ranges::end(_M_base)}; |
3209 | else |
3210 | return _Sentinel<__detail::__simple_view<_Vp>>{this}; |
3211 | } |
3212 | |
3213 | constexpr auto |
3214 | end() const |
3215 | requires forward_range<const _Vp> |
3216 | && is_reference_v<range_reference_t<const _Vp>> |
3217 | && input_range<range_reference_t<const _Vp>> |
3218 | { |
3219 | if constexpr (is_reference_v<range_reference_t<const _Vp>> |
3220 | && forward_range<range_reference_t<const _Vp>> |
3221 | && common_range<const _Vp> |
3222 | && common_range<range_reference_t<const _Vp>>) |
3223 | return _Iterator<true>{this, ranges::end(_M_base)}; |
3224 | else |
3225 | return _Sentinel<true>{this}; |
3226 | } |
3227 | }; |
3228 | |
3229 | template<typename _Range> |
3230 | explicit join_view(_Range&&) -> join_view<views::all_t<_Range>>; |
3231 | |
3232 | namespace views |
3233 | { |
3234 | namespace __detail |
3235 | { |
3236 | template<typename _Range> |
3237 | concept __can_join_view |
3238 | = requires { join_view<all_t<_Range>>{std::declval<_Range>()}; }; |
3239 | } // namespace __detail |
3240 | |
3241 | struct _Join : __adaptor::_RangeAdaptorClosure<_Join> |
3242 | { |
3243 | template<viewable_range _Range> |
3244 | requires __detail::__can_join_view<_Range> |
3245 | constexpr auto |
3246 | operator() [[nodiscard]] (_Range&& __r) const |
3247 | { |
3248 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
3249 | // 3474. Nesting join_views is broken because of CTAD |
3250 | return join_view<all_t<_Range>>{std::forward<_Range>(__r)}; |
3251 | } |
3252 | |
3253 | static constexpr bool _S_has_simple_call_op = true; |
3254 | }; |
3255 | |
3256 | inline constexpr _Join join; |
3257 | } // namespace views |
3258 | |
3259 | namespace __detail |
3260 | { |
3261 | template<auto> |
3262 | struct __require_constant; |
3263 | |
3264 | template<typename _Range> |
3265 | concept __tiny_range = sized_range<_Range> |
3266 | && requires |
3267 | { typename __require_constant<remove_reference_t<_Range>::size()>; } |
3268 | && (remove_reference_t<_Range>::size() <= 1); |
3269 | |
3270 | template<typename _Base> |
3271 | struct __lazy_split_view_outer_iter_cat |
3272 | { }; |
3273 | |
3274 | template<forward_range _Base> |
3275 | struct __lazy_split_view_outer_iter_cat<_Base> |
3276 | { using iterator_category = input_iterator_tag; }; |
3277 | |
3278 | template<typename _Base> |
3279 | struct __lazy_split_view_inner_iter_cat |
3280 | { }; |
3281 | |
3282 | template<forward_range _Base> |
3283 | struct __lazy_split_view_inner_iter_cat<_Base> |
3284 | { |
3285 | private: |
3286 | static constexpr auto |
3287 | _S_iter_cat() |
3288 | { |
3289 | using _Cat = typename iterator_traits<iterator_t<_Base>>::iterator_category; |
3290 | if constexpr (derived_from<_Cat, forward_iterator_tag>) |
3291 | return forward_iterator_tag{}; |
3292 | else |
3293 | return _Cat{}; |
3294 | } |
3295 | public: |
3296 | using iterator_category = decltype(_S_iter_cat()); |
3297 | }; |
3298 | } |
3299 | |
3300 | template<input_range _Vp, forward_range _Pattern> |
3301 | requires view<_Vp> && view<_Pattern> |
3302 | && indirectly_comparable<iterator_t<_Vp>, iterator_t<_Pattern>, |
3303 | ranges::equal_to> |
3304 | && (forward_range<_Vp> || __detail::__tiny_range<_Pattern>) |
3305 | class lazy_split_view : public view_interface<lazy_split_view<_Vp, _Pattern>> |
3306 | { |
3307 | private: |
3308 | template<bool _Const> |
3309 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
3310 | |
3311 | template<bool _Const> |
3312 | struct _InnerIter; |
3313 | |
3314 | template<bool _Const> |
3315 | struct _OuterIter |
3316 | : __detail::__lazy_split_view_outer_iter_cat<_Base<_Const>> |
3317 | { |
3318 | private: |
3319 | using _Parent = __detail::__maybe_const_t<_Const, lazy_split_view>; |
3320 | using _Base = lazy_split_view::_Base<_Const>; |
3321 | |
3322 | constexpr bool |
3323 | __at_end() const |
3324 | { return __current() == ranges::end(_M_parent->_M_base) && !_M_trailing_empty; } |
3325 | |
3326 | // [range.lazy.split.outer] p1 |
3327 | // Many of the following specifications refer to the notional member |
3328 | // current of outer-iterator. current is equivalent to current_ if |
3329 | // V models forward_range, and parent_->current_ otherwise. |
3330 | constexpr auto& |
3331 | __current() noexcept |
3332 | { |
3333 | if constexpr (forward_range<_Vp>) |
3334 | return _M_current; |
3335 | else |
3336 | return *_M_parent->_M_current; |
3337 | } |
3338 | |
3339 | constexpr auto& |
3340 | __current() const noexcept |
3341 | { |
3342 | if constexpr (forward_range<_Vp>) |
3343 | return _M_current; |
3344 | else |
3345 | return *_M_parent->_M_current; |
3346 | } |
3347 | |
3348 | _Parent* _M_parent = nullptr; |
3349 | |
3350 | [[no_unique_address]] |
3351 | __detail::__maybe_present_t<forward_range<_Vp>, |
3352 | iterator_t<_Base>> _M_current; |
3353 | bool _M_trailing_empty = false; |
3354 | |
3355 | public: |
3356 | using iterator_concept = __conditional_t<forward_range<_Base>, |
3357 | forward_iterator_tag, |
3358 | input_iterator_tag>; |
3359 | // iterator_category defined in __lazy_split_view_outer_iter_cat |
3360 | using difference_type = range_difference_t<_Base>; |
3361 | |
3362 | struct value_type : view_interface<value_type> |
3363 | { |
3364 | private: |
3365 | _OuterIter _M_i = _OuterIter(); |
3366 | |
3367 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
3368 | // 4013. lazy_split_view::outer-iterator::value_type should not |
3369 | // provide default constructor |
3370 | constexpr explicit |
3371 | value_type(_OuterIter __i) |
3372 | : _M_i(std::move(__i)) |
3373 | { } |
3374 | |
3375 | friend _OuterIter; |
3376 | |
3377 | public: |
3378 | constexpr _InnerIter<_Const> |
3379 | begin() const |
3380 | { return _InnerIter<_Const>{_M_i}; } |
3381 | |
3382 | constexpr default_sentinel_t |
3383 | end() const noexcept |
3384 | { return default_sentinel; } |
3385 | }; |
3386 | |
3387 | _OuterIter() = default; |
3388 | |
3389 | constexpr explicit |
3390 | _OuterIter(_Parent* __parent) requires (!forward_range<_Base>) |
3391 | : _M_parent(__parent) |
3392 | { } |
3393 | |
3394 | constexpr |
3395 | _OuterIter(_Parent* __parent, iterator_t<_Base> __current) |
3396 | requires forward_range<_Base> |
3397 | : _M_parent(__parent), |
3398 | _M_current(std::move(__current)) |
3399 | { } |
3400 | |
3401 | constexpr |
3402 | _OuterIter(_OuterIter<!_Const> __i) |
3403 | requires _Const |
3404 | && convertible_to<iterator_t<_Vp>, iterator_t<_Base>> |
3405 | : _M_parent(__i._M_parent), _M_current(std::move(__i._M_current)), |
3406 | _M_trailing_empty(__i._M_trailing_empty) |
3407 | { } |
3408 | |
3409 | constexpr value_type |
3410 | operator*() const |
3411 | { return value_type{*this}; } |
3412 | |
3413 | constexpr _OuterIter& |
3414 | operator++() |
3415 | { |
3416 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
3417 | // 3505. lazy_split_view::outer-iterator::operator++ misspecified |
3418 | const auto __end = ranges::end(_M_parent->_M_base); |
3419 | if (__current() == __end) |
3420 | { |
3421 | _M_trailing_empty = false; |
3422 | return *this; |
3423 | } |
3424 | const auto [__pbegin, __pend] = subrange{_M_parent->_M_pattern}; |
3425 | if (__pbegin == __pend) |
3426 | ++__current(); |
3427 | else if constexpr (__detail::__tiny_range<_Pattern>) |
3428 | { |
3429 | __current() = ranges::find(std::move(__current()), __end, |
3430 | *__pbegin); |
3431 | if (__current() != __end) |
3432 | { |
3433 | ++__current(); |
3434 | if (__current() == __end) |
3435 | _M_trailing_empty = true; |
3436 | } |
3437 | } |
3438 | else |
3439 | do |
3440 | { |
3441 | auto [__b, __p] |
3442 | = ranges::mismatch(__current(), __end, __pbegin, __pend); |
3443 | if (__p == __pend) |
3444 | { |
3445 | __current() = __b; |
3446 | if (__current() == __end) |
3447 | _M_trailing_empty = true; |
3448 | break; |
3449 | } |
3450 | } while (++__current() != __end); |
3451 | return *this; |
3452 | } |
3453 | |
3454 | constexpr decltype(auto) |
3455 | operator++(int) |
3456 | { |
3457 | if constexpr (forward_range<_Base>) |
3458 | { |
3459 | auto __tmp = *this; |
3460 | ++*this; |
3461 | return __tmp; |
3462 | } |
3463 | else |
3464 | ++*this; |
3465 | } |
3466 | |
3467 | friend constexpr bool |
3468 | operator==(const _OuterIter& __x, const _OuterIter& __y) |
3469 | requires forward_range<_Base> |
3470 | { |
3471 | return __x._M_current == __y._M_current |
3472 | && __x._M_trailing_empty == __y._M_trailing_empty; |
3473 | } |
3474 | |
3475 | friend constexpr bool |
3476 | operator==(const _OuterIter& __x, default_sentinel_t) |
3477 | { return __x.__at_end(); }; |
3478 | |
3479 | friend _OuterIter<!_Const>; |
3480 | friend _InnerIter<_Const>; |
3481 | }; |
3482 | |
3483 | template<bool _Const> |
3484 | struct _InnerIter |
3485 | : __detail::__lazy_split_view_inner_iter_cat<_Base<_Const>> |
3486 | { |
3487 | private: |
3488 | using _Base = lazy_split_view::_Base<_Const>; |
3489 | |
3490 | constexpr bool |
3491 | __at_end() const |
3492 | { |
3493 | auto [__pcur, __pend] = subrange{_M_i._M_parent->_M_pattern}; |
3494 | auto __end = ranges::end(_M_i._M_parent->_M_base); |
3495 | if constexpr (__detail::__tiny_range<_Pattern>) |
3496 | { |
3497 | const auto& __cur = _M_i_current(); |
3498 | if (__cur == __end) |
3499 | return true; |
3500 | if (__pcur == __pend) |
3501 | return _M_incremented; |
3502 | return *__cur == *__pcur; |
3503 | } |
3504 | else |
3505 | { |
3506 | auto __cur = _M_i_current(); |
3507 | if (__cur == __end) |
3508 | return true; |
3509 | if (__pcur == __pend) |
3510 | return _M_incremented; |
3511 | do |
3512 | { |
3513 | if (*__cur != *__pcur) |
3514 | return false; |
3515 | if (++__pcur == __pend) |
3516 | return true; |
3517 | } while (++__cur != __end); |
3518 | return false; |
3519 | } |
3520 | } |
3521 | |
3522 | constexpr auto& |
3523 | _M_i_current() noexcept |
3524 | { return _M_i.__current(); } |
3525 | |
3526 | constexpr auto& |
3527 | _M_i_current() const noexcept |
3528 | { return _M_i.__current(); } |
3529 | |
3530 | _OuterIter<_Const> _M_i = _OuterIter<_Const>(); |
3531 | bool _M_incremented = false; |
3532 | |
3533 | public: |
3534 | using iterator_concept |
3535 | = typename _OuterIter<_Const>::iterator_concept; |
3536 | // iterator_category defined in __lazy_split_view_inner_iter_cat |
3537 | using value_type = range_value_t<_Base>; |
3538 | using difference_type = range_difference_t<_Base>; |
3539 | |
3540 | _InnerIter() = default; |
3541 | |
3542 | constexpr explicit |
3543 | _InnerIter(_OuterIter<_Const> __i) |
3544 | : _M_i(std::move(__i)) |
3545 | { } |
3546 | |
3547 | constexpr const iterator_t<_Base>& |
3548 | base() const& noexcept |
3549 | { return _M_i_current(); } |
3550 | |
3551 | constexpr iterator_t<_Base> |
3552 | base() && requires forward_range<_Vp> |
3553 | { return std::move(_M_i_current()); } |
3554 | |
3555 | constexpr decltype(auto) |
3556 | operator*() const |
3557 | { return *_M_i_current(); } |
3558 | |
3559 | constexpr _InnerIter& |
3560 | operator++() |
3561 | { |
3562 | _M_incremented = true; |
3563 | if constexpr (!forward_range<_Base>) |
3564 | if constexpr (_Pattern::size() == 0) |
3565 | return *this; |
3566 | ++_M_i_current(); |
3567 | return *this; |
3568 | } |
3569 | |
3570 | constexpr decltype(auto) |
3571 | operator++(int) |
3572 | { |
3573 | if constexpr (forward_range<_Base>) |
3574 | { |
3575 | auto __tmp = *this; |
3576 | ++*this; |
3577 | return __tmp; |
3578 | } |
3579 | else |
3580 | ++*this; |
3581 | } |
3582 | |
3583 | friend constexpr bool |
3584 | operator==(const _InnerIter& __x, const _InnerIter& __y) |
3585 | requires forward_range<_Base> |
3586 | { return __x._M_i == __y._M_i; } |
3587 | |
3588 | friend constexpr bool |
3589 | operator==(const _InnerIter& __x, default_sentinel_t) |
3590 | { return __x.__at_end(); } |
3591 | |
3592 | friend constexpr decltype(auto) |
3593 | iter_move(const _InnerIter& __i) |
3594 | noexcept(noexcept(ranges::iter_move(__i._M_i_current()))) |
3595 | { return ranges::iter_move(__i._M_i_current()); } |
3596 | |
3597 | friend constexpr void |
3598 | iter_swap(const _InnerIter& __x, const _InnerIter& __y) |
3599 | noexcept(noexcept(ranges::iter_swap(__x._M_i_current(), |
3600 | __y._M_i_current()))) |
3601 | requires indirectly_swappable<iterator_t<_Base>> |
3602 | { ranges::iter_swap(__x._M_i_current(), __y._M_i_current()); } |
3603 | }; |
3604 | |
3605 | _Vp _M_base = _Vp(); |
3606 | _Pattern _M_pattern = _Pattern(); |
3607 | [[no_unique_address]] |
3608 | __detail::__maybe_present_t<!forward_range<_Vp>, |
3609 | __detail::__non_propagating_cache<iterator_t<_Vp>>> _M_current; |
3610 | |
3611 | |
3612 | public: |
3613 | lazy_split_view() requires (default_initializable<_Vp> |
3614 | && default_initializable<_Pattern>) |
3615 | = default; |
3616 | |
3617 | constexpr |
3618 | lazy_split_view(_Vp __base, _Pattern __pattern) |
3619 | : _M_base(std::move(__base)), _M_pattern(std::move(__pattern)) |
3620 | { } |
3621 | |
3622 | template<input_range _Range> |
3623 | requires constructible_from<_Vp, views::all_t<_Range>> |
3624 | && constructible_from<_Pattern, single_view<range_value_t<_Range>>> |
3625 | constexpr |
3626 | lazy_split_view(_Range&& __r, range_value_t<_Range> __e) |
3627 | : _M_base(views::all(std::forward<_Range>(__r))), |
3628 | _M_pattern(views::single(std::move(__e))) |
3629 | { } |
3630 | |
3631 | constexpr _Vp |
3632 | base() const& requires copy_constructible<_Vp> |
3633 | { return _M_base; } |
3634 | |
3635 | constexpr _Vp |
3636 | base() && |
3637 | { return std::move(_M_base); } |
3638 | |
3639 | constexpr auto |
3640 | begin() |
3641 | { |
3642 | if constexpr (forward_range<_Vp>) |
3643 | { |
3644 | constexpr bool __simple |
3645 | = __detail::__simple_view<_Vp> && __detail::__simple_view<_Pattern>; |
3646 | return _OuterIter<__simple>{this, ranges::begin(_M_base)}; |
3647 | } |
3648 | else |
3649 | { |
3650 | _M_current = ranges::begin(_M_base); |
3651 | return _OuterIter<false>{this}; |
3652 | } |
3653 | } |
3654 | |
3655 | constexpr auto |
3656 | begin() const requires forward_range<_Vp> && forward_range<const _Vp> |
3657 | { |
3658 | return _OuterIter<true>{this, ranges::begin(_M_base)}; |
3659 | } |
3660 | |
3661 | constexpr auto |
3662 | end() requires forward_range<_Vp> && common_range<_Vp> |
3663 | { |
3664 | constexpr bool __simple |
3665 | = __detail::__simple_view<_Vp> && __detail::__simple_view<_Pattern>; |
3666 | return _OuterIter<__simple>{this, ranges::end(_M_base)}; |
3667 | } |
3668 | |
3669 | constexpr auto |
3670 | end() const |
3671 | { |
3672 | if constexpr (forward_range<_Vp> |
3673 | && forward_range<const _Vp> |
3674 | && common_range<const _Vp>) |
3675 | return _OuterIter<true>{this, ranges::end(_M_base)}; |
3676 | else |
3677 | return default_sentinel; |
3678 | } |
3679 | }; |
3680 | |
3681 | template<typename _Range, typename _Pattern> |
3682 | lazy_split_view(_Range&&, _Pattern&&) |
3683 | -> lazy_split_view<views::all_t<_Range>, views::all_t<_Pattern>>; |
3684 | |
3685 | template<input_range _Range> |
3686 | lazy_split_view(_Range&&, range_value_t<_Range>) |
3687 | -> lazy_split_view<views::all_t<_Range>, single_view<range_value_t<_Range>>>; |
3688 | |
3689 | namespace views |
3690 | { |
3691 | namespace __detail |
3692 | { |
3693 | template<typename _Range, typename _Pattern> |
3694 | concept __can_lazy_split_view |
3695 | = requires { lazy_split_view(std::declval<_Range>(), std::declval<_Pattern>()); }; |
3696 | } // namespace __detail |
3697 | |
3698 | struct _LazySplit : __adaptor::_RangeAdaptor<_LazySplit> |
3699 | { |
3700 | template<viewable_range _Range, typename _Pattern> |
3701 | requires __detail::__can_lazy_split_view<_Range, _Pattern> |
3702 | constexpr auto |
3703 | operator() [[nodiscard]] (_Range&& __r, _Pattern&& __f) const |
3704 | { |
3705 | return lazy_split_view(std::forward<_Range>(__r), std::forward<_Pattern>(__f)); |
3706 | } |
3707 | |
3708 | using _RangeAdaptor<_LazySplit>::operator(); |
3709 | static constexpr int _S_arity = 2; |
3710 | // The pattern argument of views::lazy_split is not always simple -- it can be |
3711 | // a non-view range, the value category of which affects whether the call |
3712 | // is well-formed. But a scalar or a view pattern argument is surely |
3713 | // simple. |
3714 | template<typename _Pattern> |
3715 | static constexpr bool |
3716 | = is_scalar_v<_Pattern> || (view<_Pattern> |
3717 | && copy_constructible<_Pattern>); |
3718 | }; |
3719 | |
3720 | inline constexpr _LazySplit lazy_split; |
3721 | } // namespace views |
3722 | |
3723 | template<forward_range _Vp, forward_range _Pattern> |
3724 | requires view<_Vp> && view<_Pattern> |
3725 | && indirectly_comparable<iterator_t<_Vp>, iterator_t<_Pattern>, |
3726 | ranges::equal_to> |
3727 | class split_view : public view_interface<split_view<_Vp, _Pattern>> |
3728 | { |
3729 | private: |
3730 | _Vp _M_base = _Vp(); |
3731 | _Pattern _M_pattern = _Pattern(); |
3732 | __detail::__non_propagating_cache<subrange<iterator_t<_Vp>>> _M_cached_begin; |
3733 | |
3734 | struct _Iterator; |
3735 | struct _Sentinel; |
3736 | |
3737 | public: |
3738 | split_view() requires (default_initializable<_Vp> |
3739 | && default_initializable<_Pattern>) |
3740 | = default; |
3741 | |
3742 | constexpr |
3743 | split_view(_Vp __base, _Pattern __pattern) |
3744 | : _M_base(std::move(__base)), _M_pattern(std::move(__pattern)) |
3745 | { } |
3746 | |
3747 | template<forward_range _Range> |
3748 | requires constructible_from<_Vp, views::all_t<_Range>> |
3749 | && constructible_from<_Pattern, single_view<range_value_t<_Range>>> |
3750 | constexpr |
3751 | split_view(_Range&& __r, range_value_t<_Range> __e) |
3752 | : _M_base(views::all(std::forward<_Range>(__r))), |
3753 | _M_pattern(views::single(std::move(__e))) |
3754 | { } |
3755 | |
3756 | constexpr _Vp |
3757 | base() const& requires copy_constructible<_Vp> |
3758 | { return _M_base; } |
3759 | |
3760 | constexpr _Vp |
3761 | base() && |
3762 | { return std::move(_M_base); } |
3763 | |
3764 | constexpr _Iterator |
3765 | begin() |
3766 | { |
3767 | if (!_M_cached_begin) |
3768 | _M_cached_begin = _M_find_next(it: ranges::begin(_M_base)); |
3769 | return {this, ranges::begin(_M_base), *_M_cached_begin}; |
3770 | } |
3771 | |
3772 | constexpr auto |
3773 | end() |
3774 | { |
3775 | if constexpr (common_range<_Vp>) |
3776 | return _Iterator{this, ranges::end(_M_base), {}}; |
3777 | else |
3778 | return _Sentinel{this}; |
3779 | } |
3780 | |
3781 | constexpr subrange<iterator_t<_Vp>> |
3782 | _M_find_next(iterator_t<_Vp> __it) |
3783 | { |
3784 | auto [__b, __e] = ranges::search(subrange(__it, ranges::end(_M_base)), _M_pattern); |
3785 | if (__b != ranges::end(_M_base) && ranges::empty(_M_pattern)) |
3786 | { |
3787 | ++__b; |
3788 | ++__e; |
3789 | } |
3790 | return {__b, __e}; |
3791 | } |
3792 | |
3793 | private: |
3794 | struct _Iterator |
3795 | { |
3796 | private: |
3797 | split_view* _M_parent = nullptr; |
3798 | iterator_t<_Vp> _M_cur = iterator_t<_Vp>(); |
3799 | subrange<iterator_t<_Vp>> _M_next = subrange<iterator_t<_Vp>>(); |
3800 | bool _M_trailing_empty = false; |
3801 | |
3802 | friend struct _Sentinel; |
3803 | |
3804 | public: |
3805 | using iterator_concept = forward_iterator_tag; |
3806 | using iterator_category = input_iterator_tag; |
3807 | using value_type = subrange<iterator_t<_Vp>>; |
3808 | using difference_type = range_difference_t<_Vp>; |
3809 | |
3810 | _Iterator() = default; |
3811 | |
3812 | constexpr |
3813 | _Iterator(split_view* __parent, |
3814 | iterator_t<_Vp> __current, |
3815 | subrange<iterator_t<_Vp>> __next) |
3816 | : _M_parent(__parent), |
3817 | _M_cur(std::move(__current)), |
3818 | _M_next(std::move(__next)) |
3819 | { } |
3820 | |
3821 | constexpr iterator_t<_Vp> |
3822 | base() const |
3823 | { return _M_cur; } |
3824 | |
3825 | constexpr value_type |
3826 | operator*() const |
3827 | { return {_M_cur, _M_next.begin()}; } |
3828 | |
3829 | constexpr _Iterator& |
3830 | operator++() |
3831 | { |
3832 | _M_cur = _M_next.begin(); |
3833 | if (_M_cur != ranges::end(_M_parent->_M_base)) |
3834 | { |
3835 | _M_cur = _M_next.end(); |
3836 | if (_M_cur == ranges::end(_M_parent->_M_base)) |
3837 | { |
3838 | _M_trailing_empty = true; |
3839 | _M_next = {_M_cur, _M_cur}; |
3840 | } |
3841 | else |
3842 | _M_next = _M_parent->_M_find_next(it: _M_cur); |
3843 | } |
3844 | else |
3845 | _M_trailing_empty = false; |
3846 | return *this; |
3847 | } |
3848 | |
3849 | constexpr _Iterator |
3850 | operator++(int) |
3851 | { |
3852 | auto __tmp = *this; |
3853 | ++*this; |
3854 | return __tmp; |
3855 | } |
3856 | |
3857 | friend constexpr bool |
3858 | operator==(const _Iterator& __x, const _Iterator& __y) |
3859 | { |
3860 | return __x._M_cur == __y._M_cur |
3861 | && __x._M_trailing_empty == __y._M_trailing_empty; |
3862 | } |
3863 | }; |
3864 | |
3865 | struct _Sentinel |
3866 | { |
3867 | private: |
3868 | sentinel_t<_Vp> _M_end = sentinel_t<_Vp>(); |
3869 | |
3870 | constexpr bool |
3871 | _M_equal(const _Iterator& __x) const |
3872 | { return __x._M_cur == _M_end && !__x._M_trailing_empty; } |
3873 | |
3874 | public: |
3875 | _Sentinel() = default; |
3876 | |
3877 | constexpr explicit |
3878 | _Sentinel(split_view* __parent) |
3879 | : _M_end(ranges::end(__parent->_M_base)) |
3880 | { } |
3881 | |
3882 | friend constexpr bool |
3883 | operator==(const _Iterator& __x, const _Sentinel& __y) |
3884 | { return __y._M_equal(__x); } |
3885 | }; |
3886 | }; |
3887 | |
3888 | template<typename _Range, typename _Pattern> |
3889 | split_view(_Range&&, _Pattern&&) |
3890 | -> split_view<views::all_t<_Range>, views::all_t<_Pattern>>; |
3891 | |
3892 | template<forward_range _Range> |
3893 | split_view(_Range&&, range_value_t<_Range>) |
3894 | -> split_view<views::all_t<_Range>, single_view<range_value_t<_Range>>>; |
3895 | |
3896 | namespace views |
3897 | { |
3898 | namespace __detail |
3899 | { |
3900 | template<typename _Range, typename _Pattern> |
3901 | concept __can_split_view |
3902 | = requires { split_view(std::declval<_Range>(), std::declval<_Pattern>()); }; |
3903 | } // namespace __detail |
3904 | |
3905 | struct _Split : __adaptor::_RangeAdaptor<_Split> |
3906 | { |
3907 | template<viewable_range _Range, typename _Pattern> |
3908 | requires __detail::__can_split_view<_Range, _Pattern> |
3909 | constexpr auto |
3910 | operator() [[nodiscard]] (_Range&& __r, _Pattern&& __f) const |
3911 | { |
3912 | return split_view(std::forward<_Range>(__r), std::forward<_Pattern>(__f)); |
3913 | } |
3914 | |
3915 | using _RangeAdaptor<_Split>::operator(); |
3916 | static constexpr int _S_arity = 2; |
3917 | template<typename _Pattern> |
3918 | static constexpr bool |
3919 | = _LazySplit::_S_has_simple_extra_args<_Pattern>; |
3920 | }; |
3921 | |
3922 | inline constexpr _Split split; |
3923 | } // namespace views |
3924 | |
3925 | namespace views |
3926 | { |
3927 | struct _Counted |
3928 | { |
3929 | template<input_or_output_iterator _Iter> |
3930 | constexpr auto |
3931 | operator() [[nodiscard]] (_Iter __i, iter_difference_t<_Iter> __n) const |
3932 | { |
3933 | if constexpr (contiguous_iterator<_Iter>) |
3934 | return span(std::__to_address(__i), __n); |
3935 | else if constexpr (random_access_iterator<_Iter>) |
3936 | return subrange(__i, __i + __n); |
3937 | else |
3938 | return subrange(counted_iterator(std::move(__i), __n), |
3939 | default_sentinel); |
3940 | } |
3941 | }; |
3942 | |
3943 | inline constexpr _Counted counted{}; |
3944 | } // namespace views |
3945 | |
3946 | template<view _Vp> |
3947 | requires (!common_range<_Vp>) && copyable<iterator_t<_Vp>> |
3948 | class common_view : public view_interface<common_view<_Vp>> |
3949 | { |
3950 | private: |
3951 | _Vp _M_base = _Vp(); |
3952 | |
3953 | public: |
3954 | common_view() requires default_initializable<_Vp> = default; |
3955 | |
3956 | constexpr explicit |
3957 | common_view(_Vp __r) |
3958 | : _M_base(std::move(__r)) |
3959 | { } |
3960 | |
3961 | constexpr _Vp |
3962 | base() const& requires copy_constructible<_Vp> |
3963 | { return _M_base; } |
3964 | |
3965 | constexpr _Vp |
3966 | base() && |
3967 | { return std::move(_M_base); } |
3968 | |
3969 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
3970 | // 4012. common_view::begin/end are missing the simple-view check |
3971 | constexpr auto |
3972 | begin() requires (!__detail::__simple_view<_Vp>) |
3973 | { |
3974 | if constexpr (random_access_range<_Vp> && sized_range<_Vp>) |
3975 | return ranges::begin(_M_base); |
3976 | else |
3977 | return common_iterator<iterator_t<_Vp>, sentinel_t<_Vp>> |
3978 | (ranges::begin(_M_base)); |
3979 | } |
3980 | |
3981 | constexpr auto |
3982 | begin() const requires range<const _Vp> |
3983 | { |
3984 | if constexpr (random_access_range<const _Vp> && sized_range<const _Vp>) |
3985 | return ranges::begin(_M_base); |
3986 | else |
3987 | return common_iterator<iterator_t<const _Vp>, sentinel_t<const _Vp>> |
3988 | (ranges::begin(_M_base)); |
3989 | } |
3990 | |
3991 | constexpr auto |
3992 | end() requires (!__detail::__simple_view<_Vp>) |
3993 | { |
3994 | if constexpr (random_access_range<_Vp> && sized_range<_Vp>) |
3995 | return ranges::begin(_M_base) + ranges::size(_M_base); |
3996 | else |
3997 | return common_iterator<iterator_t<_Vp>, sentinel_t<_Vp>> |
3998 | (ranges::end(_M_base)); |
3999 | } |
4000 | |
4001 | constexpr auto |
4002 | end() const requires range<const _Vp> |
4003 | { |
4004 | if constexpr (random_access_range<const _Vp> && sized_range<const _Vp>) |
4005 | return ranges::begin(_M_base) + ranges::size(_M_base); |
4006 | else |
4007 | return common_iterator<iterator_t<const _Vp>, sentinel_t<const _Vp>> |
4008 | (ranges::end(_M_base)); |
4009 | } |
4010 | |
4011 | constexpr auto |
4012 | size() requires sized_range<_Vp> |
4013 | { return ranges::size(_M_base); } |
4014 | |
4015 | constexpr auto |
4016 | size() const requires sized_range<const _Vp> |
4017 | { return ranges::size(_M_base); } |
4018 | }; |
4019 | |
4020 | template<typename _Range> |
4021 | common_view(_Range&&) -> common_view<views::all_t<_Range>>; |
4022 | |
4023 | template<typename _Tp> |
4024 | inline constexpr bool enable_borrowed_range<common_view<_Tp>> |
4025 | = enable_borrowed_range<_Tp>; |
4026 | |
4027 | namespace views |
4028 | { |
4029 | namespace __detail |
4030 | { |
4031 | template<typename _Range> |
4032 | concept __already_common = common_range<_Range> |
4033 | && requires { views::all(std::declval<_Range>()); }; |
4034 | |
4035 | template<typename _Range> |
4036 | concept __can_common_view |
4037 | = requires { common_view{std::declval<_Range>()}; }; |
4038 | } // namespace __detail |
4039 | |
4040 | struct _Common : __adaptor::_RangeAdaptorClosure<_Common> |
4041 | { |
4042 | template<viewable_range _Range> |
4043 | requires __detail::__already_common<_Range> |
4044 | || __detail::__can_common_view<_Range> |
4045 | constexpr auto |
4046 | operator() [[nodiscard]] (_Range&& __r) const |
4047 | { |
4048 | if constexpr (__detail::__already_common<_Range>) |
4049 | return views::all(std::forward<_Range>(__r)); |
4050 | else |
4051 | return common_view{std::forward<_Range>(__r)}; |
4052 | } |
4053 | |
4054 | static constexpr bool _S_has_simple_call_op = true; |
4055 | }; |
4056 | |
4057 | inline constexpr _Common common; |
4058 | } // namespace views |
4059 | |
4060 | template<view _Vp> |
4061 | requires bidirectional_range<_Vp> |
4062 | class reverse_view : public view_interface<reverse_view<_Vp>> |
4063 | { |
4064 | private: |
4065 | static constexpr bool _S_needs_cached_begin |
4066 | = !common_range<_Vp> && !(random_access_range<_Vp> |
4067 | && sized_sentinel_for<sentinel_t<_Vp>, |
4068 | iterator_t<_Vp>>); |
4069 | |
4070 | _Vp _M_base = _Vp(); |
4071 | [[no_unique_address]] |
4072 | __detail::__maybe_present_t<_S_needs_cached_begin, |
4073 | __detail::_CachedPosition<_Vp>> |
4074 | _M_cached_begin; |
4075 | |
4076 | public: |
4077 | reverse_view() requires default_initializable<_Vp> = default; |
4078 | |
4079 | constexpr explicit |
4080 | reverse_view(_Vp __r) |
4081 | : _M_base(std::move(__r)) |
4082 | { } |
4083 | |
4084 | constexpr _Vp |
4085 | base() const& requires copy_constructible<_Vp> |
4086 | { return _M_base; } |
4087 | |
4088 | constexpr _Vp |
4089 | base() && |
4090 | { return std::move(_M_base); } |
4091 | |
4092 | constexpr reverse_iterator<iterator_t<_Vp>> |
4093 | begin() |
4094 | { |
4095 | if constexpr (_S_needs_cached_begin) |
4096 | if (_M_cached_begin._M_has_value()) |
4097 | return std::make_reverse_iterator(_M_cached_begin._M_get(_M_base)); |
4098 | |
4099 | auto __it = ranges::next(ranges::begin(_M_base), ranges::end(_M_base)); |
4100 | if constexpr (_S_needs_cached_begin) |
4101 | _M_cached_begin._M_set(_M_base, __it); |
4102 | return std::make_reverse_iterator(std::move(__it)); |
4103 | } |
4104 | |
4105 | constexpr auto |
4106 | begin() requires common_range<_Vp> |
4107 | { return std::make_reverse_iterator(ranges::end(_M_base)); } |
4108 | |
4109 | constexpr auto |
4110 | begin() const requires common_range<const _Vp> |
4111 | { return std::make_reverse_iterator(ranges::end(_M_base)); } |
4112 | |
4113 | constexpr reverse_iterator<iterator_t<_Vp>> |
4114 | end() |
4115 | { return std::make_reverse_iterator(ranges::begin(_M_base)); } |
4116 | |
4117 | constexpr auto |
4118 | end() const requires common_range<const _Vp> |
4119 | { return std::make_reverse_iterator(ranges::begin(_M_base)); } |
4120 | |
4121 | constexpr auto |
4122 | size() requires sized_range<_Vp> |
4123 | { return ranges::size(_M_base); } |
4124 | |
4125 | constexpr auto |
4126 | size() const requires sized_range<const _Vp> |
4127 | { return ranges::size(_M_base); } |
4128 | }; |
4129 | |
4130 | template<typename _Range> |
4131 | reverse_view(_Range&&) -> reverse_view<views::all_t<_Range>>; |
4132 | |
4133 | template<typename _Tp> |
4134 | inline constexpr bool enable_borrowed_range<reverse_view<_Tp>> |
4135 | = enable_borrowed_range<_Tp>; |
4136 | |
4137 | namespace views |
4138 | { |
4139 | namespace __detail |
4140 | { |
4141 | template<typename> |
4142 | inline constexpr bool __is_reversible_subrange = false; |
4143 | |
4144 | template<typename _Iter, subrange_kind _Kind> |
4145 | inline constexpr bool |
4146 | __is_reversible_subrange<subrange<reverse_iterator<_Iter>, |
4147 | reverse_iterator<_Iter>, |
4148 | _Kind>> = true; |
4149 | |
4150 | template<typename> |
4151 | inline constexpr bool __is_reverse_view = false; |
4152 | |
4153 | template<typename _Vp> |
4154 | inline constexpr bool __is_reverse_view<reverse_view<_Vp>> = true; |
4155 | |
4156 | template<typename _Range> |
4157 | concept __can_reverse_view |
4158 | = requires { reverse_view{std::declval<_Range>()}; }; |
4159 | } // namespace __detail |
4160 | |
4161 | struct _Reverse : __adaptor::_RangeAdaptorClosure<_Reverse> |
4162 | { |
4163 | template<viewable_range _Range> |
4164 | requires __detail::__is_reverse_view<remove_cvref_t<_Range>> |
4165 | || __detail::__is_reversible_subrange<remove_cvref_t<_Range>> |
4166 | || __detail::__can_reverse_view<_Range> |
4167 | constexpr auto |
4168 | operator() [[nodiscard]] (_Range&& __r) const |
4169 | { |
4170 | using _Tp = remove_cvref_t<_Range>; |
4171 | if constexpr (__detail::__is_reverse_view<_Tp>) |
4172 | return std::forward<_Range>(__r).base(); |
4173 | else if constexpr (__detail::__is_reversible_subrange<_Tp>) |
4174 | { |
4175 | using _Iter = decltype(ranges::begin(__r).base()); |
4176 | if constexpr (sized_range<_Tp>) |
4177 | return subrange<_Iter, _Iter, subrange_kind::sized> |
4178 | {__r.end().base(), __r.begin().base(), __r.size()}; |
4179 | else |
4180 | return subrange<_Iter, _Iter, subrange_kind::unsized> |
4181 | {__r.end().base(), __r.begin().base()}; |
4182 | } |
4183 | else |
4184 | return reverse_view{std::forward<_Range>(__r)}; |
4185 | } |
4186 | |
4187 | static constexpr bool _S_has_simple_call_op = true; |
4188 | }; |
4189 | |
4190 | inline constexpr _Reverse reverse; |
4191 | } // namespace views |
4192 | |
4193 | namespace __detail |
4194 | { |
4195 | #if __cpp_lib_tuple_like // >= C++23 |
4196 | template<typename _Tp, size_t _Nm> |
4197 | concept __has_tuple_element = __tuple_like<_Tp> && _Nm < tuple_size_v<_Tp>; |
4198 | #else |
4199 | template<typename _Tp, size_t _Nm> |
4200 | concept __has_tuple_element = requires(_Tp __t) |
4201 | { |
4202 | typename tuple_size<_Tp>::type; |
4203 | requires _Nm < tuple_size_v<_Tp>; |
4204 | typename tuple_element_t<_Nm, _Tp>; |
4205 | { std::get<_Nm>(__t) } |
4206 | -> convertible_to<const tuple_element_t<_Nm, _Tp>&>; |
4207 | }; |
4208 | #endif |
4209 | |
4210 | template<typename _Tp, size_t _Nm> |
4211 | concept __returnable_element |
4212 | = is_reference_v<_Tp> || move_constructible<tuple_element_t<_Nm, _Tp>>; |
4213 | } |
4214 | |
4215 | template<input_range _Vp, size_t _Nm> |
4216 | requires view<_Vp> |
4217 | && __detail::__has_tuple_element<range_value_t<_Vp>, _Nm> |
4218 | && __detail::__has_tuple_element<remove_reference_t<range_reference_t<_Vp>>, |
4219 | _Nm> |
4220 | && __detail::__returnable_element<range_reference_t<_Vp>, _Nm> |
4221 | class elements_view : public view_interface<elements_view<_Vp, _Nm>> |
4222 | { |
4223 | public: |
4224 | elements_view() requires default_initializable<_Vp> = default; |
4225 | |
4226 | constexpr explicit |
4227 | elements_view(_Vp __base) |
4228 | : _M_base(std::move(__base)) |
4229 | { } |
4230 | |
4231 | constexpr _Vp |
4232 | base() const& requires copy_constructible<_Vp> |
4233 | { return _M_base; } |
4234 | |
4235 | constexpr _Vp |
4236 | base() && |
4237 | { return std::move(_M_base); } |
4238 | |
4239 | constexpr auto |
4240 | begin() requires (!__detail::__simple_view<_Vp>) |
4241 | { return _Iterator<false>(ranges::begin(_M_base)); } |
4242 | |
4243 | constexpr auto |
4244 | begin() const requires range<const _Vp> |
4245 | { return _Iterator<true>(ranges::begin(_M_base)); } |
4246 | |
4247 | constexpr auto |
4248 | end() requires (!__detail::__simple_view<_Vp> && !common_range<_Vp>) |
4249 | { return _Sentinel<false>{ranges::end(_M_base)}; } |
4250 | |
4251 | constexpr auto |
4252 | end() requires (!__detail::__simple_view<_Vp> && common_range<_Vp>) |
4253 | { return _Iterator<false>{ranges::end(_M_base)}; } |
4254 | |
4255 | constexpr auto |
4256 | end() const requires range<const _Vp> |
4257 | { return _Sentinel<true>{ranges::end(_M_base)}; } |
4258 | |
4259 | constexpr auto |
4260 | end() const requires common_range<const _Vp> |
4261 | { return _Iterator<true>{ranges::end(_M_base)}; } |
4262 | |
4263 | constexpr auto |
4264 | size() requires sized_range<_Vp> |
4265 | { return ranges::size(_M_base); } |
4266 | |
4267 | constexpr auto |
4268 | size() const requires sized_range<const _Vp> |
4269 | { return ranges::size(_M_base); } |
4270 | |
4271 | private: |
4272 | template<bool _Const> |
4273 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
4274 | |
4275 | template<bool _Const> |
4276 | struct __iter_cat |
4277 | { }; |
4278 | |
4279 | template<bool _Const> |
4280 | requires forward_range<_Base<_Const>> |
4281 | struct __iter_cat<_Const> |
4282 | { |
4283 | private: |
4284 | static auto _S_iter_cat() |
4285 | { |
4286 | using _Base = elements_view::_Base<_Const>; |
4287 | using _Cat = typename iterator_traits<iterator_t<_Base>>::iterator_category; |
4288 | using _Res = decltype((std::get<_Nm>(*std::declval<iterator_t<_Base>>()))); |
4289 | if constexpr (!is_lvalue_reference_v<_Res>) |
4290 | return input_iterator_tag{}; |
4291 | else if constexpr (derived_from<_Cat, random_access_iterator_tag>) |
4292 | return random_access_iterator_tag{}; |
4293 | else |
4294 | return _Cat{}; |
4295 | } |
4296 | public: |
4297 | using iterator_category = decltype(_S_iter_cat()); |
4298 | }; |
4299 | |
4300 | template<bool _Const> |
4301 | struct _Sentinel; |
4302 | |
4303 | template<bool _Const> |
4304 | struct _Iterator : __iter_cat<_Const> |
4305 | { |
4306 | private: |
4307 | using _Base = elements_view::_Base<_Const>; |
4308 | |
4309 | iterator_t<_Base> _M_current = iterator_t<_Base>(); |
4310 | |
4311 | static constexpr decltype(auto) |
4312 | _S_get_element(const iterator_t<_Base>& __i) |
4313 | { |
4314 | if constexpr (is_reference_v<range_reference_t<_Base>>) |
4315 | return std::get<_Nm>(*__i); |
4316 | else |
4317 | { |
4318 | using _Et = remove_cv_t<tuple_element_t<_Nm, range_reference_t<_Base>>>; |
4319 | return static_cast<_Et>(std::get<_Nm>(*__i)); |
4320 | } |
4321 | } |
4322 | |
4323 | static auto |
4324 | _S_iter_concept() |
4325 | { |
4326 | if constexpr (random_access_range<_Base>) |
4327 | return random_access_iterator_tag{}; |
4328 | else if constexpr (bidirectional_range<_Base>) |
4329 | return bidirectional_iterator_tag{}; |
4330 | else if constexpr (forward_range<_Base>) |
4331 | return forward_iterator_tag{}; |
4332 | else |
4333 | return input_iterator_tag{}; |
4334 | } |
4335 | |
4336 | friend _Iterator<!_Const>; |
4337 | |
4338 | public: |
4339 | using iterator_concept = decltype(_S_iter_concept()); |
4340 | // iterator_category defined in elements_view::__iter_cat |
4341 | using value_type |
4342 | = remove_cvref_t<tuple_element_t<_Nm, range_value_t<_Base>>>; |
4343 | using difference_type = range_difference_t<_Base>; |
4344 | |
4345 | _Iterator() requires default_initializable<iterator_t<_Base>> = default; |
4346 | |
4347 | constexpr explicit |
4348 | _Iterator(iterator_t<_Base> __current) |
4349 | : _M_current(std::move(__current)) |
4350 | { } |
4351 | |
4352 | constexpr |
4353 | _Iterator(_Iterator<!_Const> __i) |
4354 | requires _Const && convertible_to<iterator_t<_Vp>, iterator_t<_Base>> |
4355 | : _M_current(std::move(__i._M_current)) |
4356 | { } |
4357 | |
4358 | constexpr const iterator_t<_Base>& |
4359 | base() const& noexcept |
4360 | { return _M_current; } |
4361 | |
4362 | constexpr iterator_t<_Base> |
4363 | base() && |
4364 | { return std::move(_M_current); } |
4365 | |
4366 | constexpr decltype(auto) |
4367 | operator*() const |
4368 | { return _S_get_element(i: _M_current); } |
4369 | |
4370 | constexpr _Iterator& |
4371 | operator++() |
4372 | { |
4373 | ++_M_current; |
4374 | return *this; |
4375 | } |
4376 | |
4377 | constexpr void |
4378 | operator++(int) |
4379 | { ++_M_current; } |
4380 | |
4381 | constexpr _Iterator |
4382 | operator++(int) requires forward_range<_Base> |
4383 | { |
4384 | auto __tmp = *this; |
4385 | ++_M_current; |
4386 | return __tmp; |
4387 | } |
4388 | |
4389 | constexpr _Iterator& |
4390 | operator--() requires bidirectional_range<_Base> |
4391 | { |
4392 | --_M_current; |
4393 | return *this; |
4394 | } |
4395 | |
4396 | constexpr _Iterator |
4397 | operator--(int) requires bidirectional_range<_Base> |
4398 | { |
4399 | auto __tmp = *this; |
4400 | --_M_current; |
4401 | return __tmp; |
4402 | } |
4403 | |
4404 | constexpr _Iterator& |
4405 | operator+=(difference_type __n) |
4406 | requires random_access_range<_Base> |
4407 | { |
4408 | _M_current += __n; |
4409 | return *this; |
4410 | } |
4411 | |
4412 | constexpr _Iterator& |
4413 | operator-=(difference_type __n) |
4414 | requires random_access_range<_Base> |
4415 | { |
4416 | _M_current -= __n; |
4417 | return *this; |
4418 | } |
4419 | |
4420 | constexpr decltype(auto) |
4421 | operator[](difference_type __n) const |
4422 | requires random_access_range<_Base> |
4423 | { return _S_get_element(i: _M_current + __n); } |
4424 | |
4425 | friend constexpr bool |
4426 | operator==(const _Iterator& __x, const _Iterator& __y) |
4427 | requires equality_comparable<iterator_t<_Base>> |
4428 | { return __x._M_current == __y._M_current; } |
4429 | |
4430 | friend constexpr bool |
4431 | operator<(const _Iterator& __x, const _Iterator& __y) |
4432 | requires random_access_range<_Base> |
4433 | { return __x._M_current < __y._M_current; } |
4434 | |
4435 | friend constexpr bool |
4436 | operator>(const _Iterator& __x, const _Iterator& __y) |
4437 | requires random_access_range<_Base> |
4438 | { return __y._M_current < __x._M_current; } |
4439 | |
4440 | friend constexpr bool |
4441 | operator<=(const _Iterator& __x, const _Iterator& __y) |
4442 | requires random_access_range<_Base> |
4443 | { return !(__y._M_current > __x._M_current); } |
4444 | |
4445 | friend constexpr bool |
4446 | operator>=(const _Iterator& __x, const _Iterator& __y) |
4447 | requires random_access_range<_Base> |
4448 | { return !(__x._M_current > __y._M_current); } |
4449 | |
4450 | #ifdef __cpp_lib_three_way_comparison |
4451 | friend constexpr auto |
4452 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
4453 | requires random_access_range<_Base> |
4454 | && three_way_comparable<iterator_t<_Base>> |
4455 | { return __x._M_current <=> __y._M_current; } |
4456 | #endif |
4457 | |
4458 | friend constexpr _Iterator |
4459 | operator+(const _Iterator& __x, difference_type __y) |
4460 | requires random_access_range<_Base> |
4461 | { return _Iterator{__x} += __y; } |
4462 | |
4463 | friend constexpr _Iterator |
4464 | operator+(difference_type __x, const _Iterator& __y) |
4465 | requires random_access_range<_Base> |
4466 | { return __y + __x; } |
4467 | |
4468 | friend constexpr _Iterator |
4469 | operator-(const _Iterator& __x, difference_type __y) |
4470 | requires random_access_range<_Base> |
4471 | { return _Iterator{__x} -= __y; } |
4472 | |
4473 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
4474 | // 3483. transform_view::iterator's difference is overconstrained |
4475 | friend constexpr difference_type |
4476 | operator-(const _Iterator& __x, const _Iterator& __y) |
4477 | requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>> |
4478 | { return __x._M_current - __y._M_current; } |
4479 | |
4480 | template <bool> friend struct _Sentinel; |
4481 | }; |
4482 | |
4483 | template<bool _Const> |
4484 | struct _Sentinel |
4485 | { |
4486 | private: |
4487 | template<bool _Const2> |
4488 | constexpr bool |
4489 | _M_equal(const _Iterator<_Const2>& __x) const |
4490 | { return __x._M_current == _M_end; } |
4491 | |
4492 | template<bool _Const2> |
4493 | constexpr auto |
4494 | _M_distance_from(const _Iterator<_Const2>& __i) const |
4495 | { return _M_end - __i._M_current; } |
4496 | |
4497 | using _Base = elements_view::_Base<_Const>; |
4498 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
4499 | |
4500 | public: |
4501 | _Sentinel() = default; |
4502 | |
4503 | constexpr explicit |
4504 | _Sentinel(sentinel_t<_Base> __end) |
4505 | : _M_end(std::move(__end)) |
4506 | { } |
4507 | |
4508 | constexpr |
4509 | _Sentinel(_Sentinel<!_Const> __other) |
4510 | requires _Const |
4511 | && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
4512 | : _M_end(std::move(__other._M_end)) |
4513 | { } |
4514 | |
4515 | constexpr sentinel_t<_Base> |
4516 | base() const |
4517 | { return _M_end; } |
4518 | |
4519 | template<bool _Const2> |
4520 | requires sentinel_for<sentinel_t<_Base>, |
4521 | iterator_t<__detail::__maybe_const_t<_Const2, _Vp>>> |
4522 | friend constexpr bool |
4523 | operator==(const _Iterator<_Const2>& __x, const _Sentinel& __y) |
4524 | { return __y._M_equal(__x); } |
4525 | |
4526 | template<bool _Const2, |
4527 | typename _Base2 = __detail::__maybe_const_t<_Const2, _Vp>> |
4528 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> |
4529 | friend constexpr range_difference_t<_Base2> |
4530 | operator-(const _Iterator<_Const2>& __x, const _Sentinel& __y) |
4531 | { return -__y._M_distance_from(__x); } |
4532 | |
4533 | template<bool _Const2, |
4534 | typename _Base2 = __detail::__maybe_const_t<_Const2, _Vp>> |
4535 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> |
4536 | friend constexpr range_difference_t<_Base2> |
4537 | operator-(const _Sentinel& __x, const _Iterator<_Const2>& __y) |
4538 | { return __x._M_distance_from(__y); } |
4539 | |
4540 | friend _Sentinel<!_Const>; |
4541 | }; |
4542 | |
4543 | _Vp _M_base = _Vp(); |
4544 | }; |
4545 | |
4546 | template<typename _Tp, size_t _Nm> |
4547 | inline constexpr bool enable_borrowed_range<elements_view<_Tp, _Nm>> |
4548 | = enable_borrowed_range<_Tp>; |
4549 | |
4550 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
4551 | // 3563. keys_view example is broken |
4552 | template<typename _Range> |
4553 | using keys_view = elements_view<_Range, 0>; |
4554 | |
4555 | template<typename _Range> |
4556 | using values_view = elements_view<_Range, 1>; |
4557 | |
4558 | namespace views |
4559 | { |
4560 | namespace __detail |
4561 | { |
4562 | template<size_t _Nm, typename _Range> |
4563 | concept __can_elements_view |
4564 | = requires { elements_view<all_t<_Range>, _Nm>{std::declval<_Range>()}; }; |
4565 | } // namespace __detail |
4566 | |
4567 | template<size_t _Nm> |
4568 | struct _Elements : __adaptor::_RangeAdaptorClosure<_Elements<_Nm>> |
4569 | { |
4570 | template<viewable_range _Range> |
4571 | requires __detail::__can_elements_view<_Nm, _Range> |
4572 | constexpr auto |
4573 | operator() [[nodiscard]] (_Range&& __r) const |
4574 | { |
4575 | return elements_view<all_t<_Range>, _Nm>{std::forward<_Range>(__r)}; |
4576 | } |
4577 | |
4578 | static constexpr bool _S_has_simple_call_op = true; |
4579 | }; |
4580 | |
4581 | template<size_t _Nm> |
4582 | inline constexpr _Elements<_Nm> elements; |
4583 | inline constexpr auto keys = elements<0>; |
4584 | inline constexpr auto values = elements<1>; |
4585 | } // namespace views |
4586 | |
4587 | #ifdef __cpp_lib_ranges_zip // C++ >= 23 |
4588 | namespace __detail |
4589 | { |
4590 | template<typename... _Rs> |
4591 | concept __zip_is_common = (sizeof...(_Rs) == 1 && (common_range<_Rs> && ...)) |
4592 | || (!(bidirectional_range<_Rs> && ...) && (common_range<_Rs> && ...)) |
4593 | || ((random_access_range<_Rs> && ...) && (sized_range<_Rs> && ...)); |
4594 | |
4595 | template<typename _Fp, typename _Tuple> |
4596 | constexpr auto |
4597 | __tuple_transform(_Fp&& __f, _Tuple&& __tuple) |
4598 | { |
4599 | return std::apply([&]<typename... _Ts>(_Ts&&... __elts) { |
4600 | return tuple<invoke_result_t<_Fp&, _Ts>...> |
4601 | (std::__invoke(__f, std::forward<_Ts>(__elts))...); |
4602 | }, std::forward<_Tuple>(__tuple)); |
4603 | } |
4604 | |
4605 | template<typename _Fp, typename _Tuple> |
4606 | constexpr void |
4607 | __tuple_for_each(_Fp&& __f, _Tuple&& __tuple) |
4608 | { |
4609 | std::apply([&]<typename... _Ts>(_Ts&&... __elts) { |
4610 | (std::__invoke(__f, std::forward<_Ts>(__elts)), ...); |
4611 | }, std::forward<_Tuple>(__tuple)); |
4612 | } |
4613 | } // namespace __detail |
4614 | |
4615 | template<input_range... _Vs> |
4616 | requires (view<_Vs> && ...) && (sizeof...(_Vs) > 0) |
4617 | class zip_view : public view_interface<zip_view<_Vs...>> |
4618 | { |
4619 | tuple<_Vs...> _M_views; |
4620 | |
4621 | template<bool> class _Iterator; |
4622 | template<bool> class _Sentinel; |
4623 | |
4624 | public: |
4625 | zip_view() = default; |
4626 | |
4627 | constexpr explicit |
4628 | zip_view(_Vs... __views) |
4629 | : _M_views(std::move(__views)...) |
4630 | { } |
4631 | |
4632 | constexpr auto |
4633 | begin() requires (!(__detail::__simple_view<_Vs> && ...)) |
4634 | { return _Iterator<false>(__detail::__tuple_transform(ranges::begin, _M_views)); } |
4635 | |
4636 | constexpr auto |
4637 | begin() const requires (range<const _Vs> && ...) |
4638 | { return _Iterator<true>(__detail::__tuple_transform(ranges::begin, _M_views)); } |
4639 | |
4640 | constexpr auto |
4641 | end() requires (!(__detail::__simple_view<_Vs> && ...)) |
4642 | { |
4643 | if constexpr (!__detail::__zip_is_common<_Vs...>) |
4644 | return _Sentinel<false>(__detail::__tuple_transform(ranges::end, _M_views)); |
4645 | else if constexpr ((random_access_range<_Vs> && ...)) |
4646 | return begin() + iter_difference_t<_Iterator<false>>(size()); |
4647 | else |
4648 | return _Iterator<false>(__detail::__tuple_transform(ranges::end, _M_views)); |
4649 | } |
4650 | |
4651 | constexpr auto |
4652 | end() const requires (range<const _Vs> && ...) |
4653 | { |
4654 | if constexpr (!__detail::__zip_is_common<const _Vs...>) |
4655 | return _Sentinel<true>(__detail::__tuple_transform(ranges::end, _M_views)); |
4656 | else if constexpr ((random_access_range<const _Vs> && ...)) |
4657 | return begin() + iter_difference_t<_Iterator<true>>(size()); |
4658 | else |
4659 | return _Iterator<true>(__detail::__tuple_transform(ranges::end, _M_views)); |
4660 | } |
4661 | |
4662 | constexpr auto |
4663 | size() requires (sized_range<_Vs> && ...) |
4664 | { |
4665 | return std::apply([](auto... sizes) { |
4666 | using _CT = __detail::__make_unsigned_like_t<common_type_t<decltype(sizes)...>>; |
4667 | return ranges::min({_CT(sizes)...}); |
4668 | }, __detail::__tuple_transform(ranges::size, _M_views)); |
4669 | } |
4670 | |
4671 | constexpr auto |
4672 | size() const requires (sized_range<const _Vs> && ...) |
4673 | { |
4674 | return std::apply([](auto... sizes) { |
4675 | using _CT = __detail::__make_unsigned_like_t<common_type_t<decltype(sizes)...>>; |
4676 | return ranges::min({_CT(sizes)...}); |
4677 | }, __detail::__tuple_transform(ranges::size, _M_views)); |
4678 | } |
4679 | }; |
4680 | |
4681 | template<typename... _Rs> |
4682 | zip_view(_Rs&&...) -> zip_view<views::all_t<_Rs>...>; |
4683 | |
4684 | template<typename... _Views> |
4685 | inline constexpr bool enable_borrowed_range<zip_view<_Views...>> |
4686 | = (enable_borrowed_range<_Views> && ...); |
4687 | |
4688 | namespace __detail |
4689 | { |
4690 | template<bool _Const, typename... _Vs> |
4691 | concept __all_random_access |
4692 | = (random_access_range<__maybe_const_t<_Const, _Vs>> && ...); |
4693 | |
4694 | template<bool _Const, typename... _Vs> |
4695 | concept __all_bidirectional |
4696 | = (bidirectional_range<__maybe_const_t<_Const, _Vs>> && ...); |
4697 | |
4698 | template<bool _Const, typename... _Vs> |
4699 | concept __all_forward |
4700 | = (forward_range<__maybe_const_t<_Const, _Vs>> && ...); |
4701 | |
4702 | template<bool _Const, typename... _Views> |
4703 | struct __zip_view_iter_cat |
4704 | { }; |
4705 | |
4706 | template<bool _Const, typename... _Views> |
4707 | requires __all_forward<_Const, _Views...> |
4708 | struct __zip_view_iter_cat<_Const, _Views...> |
4709 | { using iterator_category = input_iterator_tag; }; |
4710 | } // namespace __detail |
4711 | |
4712 | template<input_range... _Vs> |
4713 | requires (view<_Vs> && ...) && (sizeof...(_Vs) > 0) |
4714 | template<bool _Const> |
4715 | class zip_view<_Vs...>::_Iterator |
4716 | : public __detail::__zip_view_iter_cat<_Const, _Vs...> |
4717 | { |
4718 | #ifdef __clang__ // LLVM-61763 workaround |
4719 | public: |
4720 | #endif |
4721 | tuple<iterator_t<__detail::__maybe_const_t<_Const, _Vs>>...> _M_current; |
4722 | |
4723 | constexpr explicit |
4724 | _Iterator(decltype(_M_current) __current) |
4725 | : _M_current(std::move(__current)) |
4726 | { } |
4727 | |
4728 | static auto |
4729 | _S_iter_concept() |
4730 | { |
4731 | if constexpr (__detail::__all_random_access<_Const, _Vs...>) |
4732 | return random_access_iterator_tag{}; |
4733 | else if constexpr (__detail::__all_bidirectional<_Const, _Vs...>) |
4734 | return bidirectional_iterator_tag{}; |
4735 | else if constexpr (__detail::__all_forward<_Const, _Vs...>) |
4736 | return forward_iterator_tag{}; |
4737 | else |
4738 | return input_iterator_tag{}; |
4739 | } |
4740 | |
4741 | #ifndef __clang__ // LLVM-61763 workaround |
4742 | template<move_constructible _Fp, input_range... _Ws> |
4743 | requires (view<_Ws> && ...) && (sizeof...(_Ws) > 0) && is_object_v<_Fp> |
4744 | && regular_invocable<_Fp&, range_reference_t<_Ws>...> |
4745 | && std::__detail::__can_reference<invoke_result_t<_Fp&, range_reference_t<_Ws>...>> |
4746 | friend class zip_transform_view; |
4747 | #endif |
4748 | |
4749 | public: |
4750 | // iterator_category defined in __zip_view_iter_cat |
4751 | using iterator_concept = decltype(_S_iter_concept()); |
4752 | using value_type |
4753 | = tuple<range_value_t<__detail::__maybe_const_t<_Const, _Vs>>...>; |
4754 | using difference_type |
4755 | = common_type_t<range_difference_t<__detail::__maybe_const_t<_Const, _Vs>>...>; |
4756 | |
4757 | _Iterator() = default; |
4758 | |
4759 | constexpr |
4760 | _Iterator(_Iterator<!_Const> __i) |
4761 | requires _Const |
4762 | && (convertible_to<iterator_t<_Vs>, |
4763 | iterator_t<__detail::__maybe_const_t<_Const, _Vs>>> && ...) |
4764 | : _M_current(std::move(__i._M_current)) |
4765 | { } |
4766 | |
4767 | constexpr auto |
4768 | operator*() const |
4769 | { |
4770 | auto __f = [](auto& __i) -> decltype(auto) { |
4771 | return *__i; |
4772 | }; |
4773 | return __detail::__tuple_transform(__f, _M_current); |
4774 | } |
4775 | |
4776 | constexpr _Iterator& |
4777 | operator++() |
4778 | { |
4779 | __detail::__tuple_for_each([](auto& __i) { ++__i; }, _M_current); |
4780 | return *this; |
4781 | } |
4782 | |
4783 | constexpr void |
4784 | operator++(int) |
4785 | { ++*this; } |
4786 | |
4787 | constexpr _Iterator |
4788 | operator++(int) |
4789 | requires __detail::__all_forward<_Const, _Vs...> |
4790 | { |
4791 | auto __tmp = *this; |
4792 | ++*this; |
4793 | return __tmp; |
4794 | } |
4795 | |
4796 | constexpr _Iterator& |
4797 | operator--() |
4798 | requires __detail::__all_bidirectional<_Const, _Vs...> |
4799 | { |
4800 | __detail::__tuple_for_each([](auto& __i) { --__i; }, _M_current); |
4801 | return *this; |
4802 | } |
4803 | |
4804 | constexpr _Iterator |
4805 | operator--(int) |
4806 | requires __detail::__all_bidirectional<_Const, _Vs...> |
4807 | { |
4808 | auto __tmp = *this; |
4809 | --*this; |
4810 | return __tmp; |
4811 | } |
4812 | |
4813 | constexpr _Iterator& |
4814 | operator+=(difference_type __x) |
4815 | requires __detail::__all_random_access<_Const, _Vs...> |
4816 | { |
4817 | auto __f = [&]<typename _It>(_It& __i) { |
4818 | __i += iter_difference_t<_It>(__x); |
4819 | }; |
4820 | __detail::__tuple_for_each(__f, _M_current); |
4821 | return *this; |
4822 | } |
4823 | |
4824 | constexpr _Iterator& |
4825 | operator-=(difference_type __x) |
4826 | requires __detail::__all_random_access<_Const, _Vs...> |
4827 | { |
4828 | auto __f = [&]<typename _It>(_It& __i) { |
4829 | __i -= iter_difference_t<_It>(__x); |
4830 | }; |
4831 | __detail::__tuple_for_each(__f, _M_current); |
4832 | return *this; |
4833 | } |
4834 | |
4835 | constexpr auto |
4836 | operator[](difference_type __n) const |
4837 | requires __detail::__all_random_access<_Const, _Vs...> |
4838 | { |
4839 | auto __f = [&]<typename _It>(_It& __i) -> decltype(auto) { |
4840 | return __i[iter_difference_t<_It>(__n)]; |
4841 | }; |
4842 | return __detail::__tuple_transform(__f, _M_current); |
4843 | } |
4844 | |
4845 | friend constexpr bool |
4846 | operator==(const _Iterator& __x, const _Iterator& __y) |
4847 | requires (equality_comparable<iterator_t<__detail::__maybe_const_t<_Const, _Vs>>> && ...) |
4848 | { |
4849 | if constexpr (__detail::__all_bidirectional<_Const, _Vs...>) |
4850 | return __x._M_current == __y._M_current; |
4851 | else |
4852 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
4853 | return ((std::get<_Is>(__x._M_current) == std::get<_Is>(__y._M_current)) || ...); |
4854 | }(make_index_sequence<sizeof...(_Vs)>{}); |
4855 | } |
4856 | |
4857 | friend constexpr auto |
4858 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
4859 | requires __detail::__all_random_access<_Const, _Vs...> |
4860 | { return __x._M_current <=> __y._M_current; } |
4861 | |
4862 | friend constexpr _Iterator |
4863 | operator+(const _Iterator& __i, difference_type __n) |
4864 | requires __detail::__all_random_access<_Const, _Vs...> |
4865 | { |
4866 | auto __r = __i; |
4867 | __r += __n; |
4868 | return __r; |
4869 | } |
4870 | |
4871 | friend constexpr _Iterator |
4872 | operator+(difference_type __n, const _Iterator& __i) |
4873 | requires __detail::__all_random_access<_Const, _Vs...> |
4874 | { |
4875 | auto __r = __i; |
4876 | __r += __n; |
4877 | return __r; |
4878 | } |
4879 | |
4880 | friend constexpr _Iterator |
4881 | operator-(const _Iterator& __i, difference_type __n) |
4882 | requires __detail::__all_random_access<_Const, _Vs...> |
4883 | { |
4884 | auto __r = __i; |
4885 | __r -= __n; |
4886 | return __r; |
4887 | } |
4888 | |
4889 | friend constexpr difference_type |
4890 | operator-(const _Iterator& __x, const _Iterator& __y) |
4891 | requires (sized_sentinel_for<iterator_t<__detail::__maybe_const_t<_Const, _Vs>>, |
4892 | iterator_t<__detail::__maybe_const_t<_Const, _Vs>>> && ...) |
4893 | { |
4894 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
4895 | return ranges::min({difference_type(std::get<_Is>(__x._M_current) |
4896 | - std::get<_Is>(__y._M_current))...}, |
4897 | ranges::less{}, |
4898 | [](difference_type __i) { |
4899 | return __detail::__to_unsigned_like(__i < 0 ? -__i : __i); |
4900 | }); |
4901 | }(make_index_sequence<sizeof...(_Vs)>{}); |
4902 | } |
4903 | |
4904 | friend constexpr auto |
4905 | iter_move(const _Iterator& __i) |
4906 | { return __detail::__tuple_transform(ranges::iter_move, __i._M_current); } |
4907 | |
4908 | friend constexpr void |
4909 | iter_swap(const _Iterator& __l, const _Iterator& __r) |
4910 | requires (indirectly_swappable<iterator_t<__detail::__maybe_const_t<_Const, _Vs>>> && ...) |
4911 | { |
4912 | [&]<size_t... _Is>(index_sequence<_Is...>) { |
4913 | (ranges::iter_swap(std::get<_Is>(__l._M_current), std::get<_Is>(__r._M_current)), ...); |
4914 | }(make_index_sequence<sizeof...(_Vs)>{}); |
4915 | } |
4916 | |
4917 | friend class zip_view; |
4918 | }; |
4919 | |
4920 | template<input_range... _Vs> |
4921 | requires (view<_Vs> && ...) && (sizeof...(_Vs) > 0) |
4922 | template<bool _Const> |
4923 | class zip_view<_Vs...>::_Sentinel |
4924 | { |
4925 | tuple<sentinel_t<__detail::__maybe_const_t<_Const, _Vs>>...> _M_end; |
4926 | |
4927 | constexpr explicit |
4928 | _Sentinel(decltype(_M_end) __end) |
4929 | : _M_end(__end) |
4930 | { } |
4931 | |
4932 | friend class zip_view; |
4933 | |
4934 | public: |
4935 | _Sentinel() = default; |
4936 | |
4937 | constexpr |
4938 | _Sentinel(_Sentinel<!_Const> __i) |
4939 | requires _Const |
4940 | && (convertible_to<sentinel_t<_Vs>, |
4941 | sentinel_t<__detail::__maybe_const_t<_Const, _Vs>>> && ...) |
4942 | : _M_end(std::move(__i._M_end)) |
4943 | { } |
4944 | |
4945 | template<bool _OtherConst> |
4946 | requires (sentinel_for<sentinel_t<__detail::__maybe_const_t<_Const, _Vs>>, |
4947 | iterator_t<__detail::__maybe_const_t<_OtherConst, _Vs>>> && ...) |
4948 | friend constexpr bool |
4949 | operator==(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
4950 | { |
4951 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
4952 | return ((std::get<_Is>(__x._M_current) == std::get<_Is>(__y._M_end)) || ...); |
4953 | }(make_index_sequence<sizeof...(_Vs)>{}); |
4954 | } |
4955 | |
4956 | template<bool _OtherConst> |
4957 | requires (sized_sentinel_for<sentinel_t<__detail::__maybe_const_t<_Const, _Vs>>, |
4958 | iterator_t<__detail::__maybe_const_t<_OtherConst, _Vs>>> && ...) |
4959 | friend constexpr auto |
4960 | operator-(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
4961 | { |
4962 | using _Ret |
4963 | = common_type_t<range_difference_t<__detail::__maybe_const_t<_OtherConst, _Vs>>...>; |
4964 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
4965 | return ranges::min({_Ret(std::get<_Is>(__x._M_current) - std::get<_Is>(__y._M_end))...}, |
4966 | ranges::less{}, |
4967 | [](_Ret __i) { |
4968 | return __detail::__to_unsigned_like(__i < 0 ? -__i : __i); |
4969 | }); |
4970 | }(make_index_sequence<sizeof...(_Vs)>{}); |
4971 | } |
4972 | |
4973 | template<bool _OtherConst> |
4974 | requires (sized_sentinel_for<sentinel_t<__detail::__maybe_const_t<_Const, _Vs>>, |
4975 | iterator_t<__detail::__maybe_const_t<_OtherConst, _Vs>>> && ...) |
4976 | friend constexpr auto |
4977 | operator-(const _Sentinel& __y, const _Iterator<_OtherConst>& __x) |
4978 | { return -(__x - __y); } |
4979 | }; |
4980 | |
4981 | namespace views |
4982 | { |
4983 | namespace __detail |
4984 | { |
4985 | template<typename... _Ts> |
4986 | concept __can_zip_view |
4987 | = requires { zip_view<all_t<_Ts>...>(std::declval<_Ts>()...); }; |
4988 | } |
4989 | |
4990 | struct _Zip |
4991 | { |
4992 | template<typename... _Ts> |
4993 | requires (sizeof...(_Ts) == 0 || __detail::__can_zip_view<_Ts...>) |
4994 | constexpr auto |
4995 | operator() [[nodiscard]] (_Ts&&... __ts) const |
4996 | { |
4997 | if constexpr (sizeof...(_Ts) == 0) |
4998 | return views::empty<tuple<>>; |
4999 | else |
5000 | return zip_view<all_t<_Ts>...>(std::forward<_Ts>(__ts)...); |
5001 | } |
5002 | }; |
5003 | |
5004 | inline constexpr _Zip zip; |
5005 | } |
5006 | |
5007 | namespace __detail |
5008 | { |
5009 | template<typename _Range, bool _Const> |
5010 | using __range_iter_cat |
5011 | = typename iterator_traits<iterator_t<__maybe_const_t<_Const, _Range>>>::iterator_category; |
5012 | } |
5013 | |
5014 | template<move_constructible _Fp, input_range... _Vs> |
5015 | requires (view<_Vs> && ...) && (sizeof...(_Vs) > 0) && is_object_v<_Fp> |
5016 | && regular_invocable<_Fp&, range_reference_t<_Vs>...> |
5017 | && std::__detail::__can_reference<invoke_result_t<_Fp&, range_reference_t<_Vs>...>> |
5018 | class zip_transform_view : public view_interface<zip_transform_view<_Fp, _Vs...>> |
5019 | { |
5020 | [[no_unique_address]] __detail::__box<_Fp> _M_fun; |
5021 | zip_view<_Vs...> _M_zip; |
5022 | |
5023 | using _InnerView = zip_view<_Vs...>; |
5024 | |
5025 | template<bool _Const> |
5026 | using __ziperator = iterator_t<__detail::__maybe_const_t<_Const, _InnerView>>; |
5027 | |
5028 | template<bool _Const> |
5029 | using __zentinel = sentinel_t<__detail::__maybe_const_t<_Const, _InnerView>>; |
5030 | |
5031 | template<bool _Const> |
5032 | using _Base = __detail::__maybe_const_t<_Const, _InnerView>; |
5033 | |
5034 | template<bool _Const> |
5035 | struct __iter_cat |
5036 | { }; |
5037 | |
5038 | template<bool _Const> |
5039 | requires forward_range<_Base<_Const>> |
5040 | struct __iter_cat<_Const> |
5041 | { |
5042 | private: |
5043 | static auto |
5044 | _S_iter_cat() |
5045 | { |
5046 | using __detail::__maybe_const_t; |
5047 | using __detail::__range_iter_cat; |
5048 | using _Res = invoke_result_t<__maybe_const_t<_Const, _Fp>&, |
5049 | range_reference_t<__maybe_const_t<_Const, _Vs>>...>; |
5050 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
5051 | // 3798. Rvalue reference and iterator_category |
5052 | if constexpr (!is_reference_v<_Res>) |
5053 | return input_iterator_tag{}; |
5054 | else if constexpr ((derived_from<__range_iter_cat<_Vs, _Const>, |
5055 | random_access_iterator_tag> && ...)) |
5056 | return random_access_iterator_tag{}; |
5057 | else if constexpr ((derived_from<__range_iter_cat<_Vs, _Const>, |
5058 | bidirectional_iterator_tag> && ...)) |
5059 | return bidirectional_iterator_tag{}; |
5060 | else if constexpr ((derived_from<__range_iter_cat<_Vs, _Const>, |
5061 | forward_iterator_tag> && ...)) |
5062 | return forward_iterator_tag{}; |
5063 | else |
5064 | return input_iterator_tag{}; |
5065 | } |
5066 | public: |
5067 | using iterator_category = decltype(_S_iter_cat()); |
5068 | }; |
5069 | |
5070 | template<bool> class _Iterator; |
5071 | template<bool> class _Sentinel; |
5072 | |
5073 | public: |
5074 | zip_transform_view() = default; |
5075 | |
5076 | constexpr explicit |
5077 | zip_transform_view(_Fp __fun, _Vs... __views) |
5078 | : _M_fun(std::move(__fun)), _M_zip(std::move(__views)...) |
5079 | { } |
5080 | |
5081 | constexpr auto |
5082 | begin() |
5083 | { return _Iterator<false>(*this, _M_zip.begin()); } |
5084 | |
5085 | constexpr auto |
5086 | begin() const |
5087 | requires range<const _InnerView> |
5088 | && regular_invocable<const _Fp&, range_reference_t<const _Vs>...> |
5089 | { return _Iterator<true>(*this, _M_zip.begin()); } |
5090 | |
5091 | constexpr auto |
5092 | end() |
5093 | { |
5094 | if constexpr (common_range<_InnerView>) |
5095 | return _Iterator<false>(*this, _M_zip.end()); |
5096 | else |
5097 | return _Sentinel<false>(_M_zip.end()); |
5098 | } |
5099 | |
5100 | constexpr auto |
5101 | end() const |
5102 | requires range<const _InnerView> |
5103 | && regular_invocable<const _Fp&, range_reference_t<const _Vs>...> |
5104 | { |
5105 | if constexpr (common_range<const _InnerView>) |
5106 | return _Iterator<true>(*this, _M_zip.end()); |
5107 | else |
5108 | return _Sentinel<true>(_M_zip.end()); |
5109 | } |
5110 | |
5111 | constexpr auto |
5112 | size() requires sized_range<_InnerView> |
5113 | { return _M_zip.size(); } |
5114 | |
5115 | constexpr auto |
5116 | size() const requires sized_range<const _InnerView> |
5117 | { return _M_zip.size(); } |
5118 | }; |
5119 | |
5120 | template<class _Fp, class... Rs> |
5121 | zip_transform_view(_Fp, Rs&&...) -> zip_transform_view<_Fp, views::all_t<Rs>...>; |
5122 | |
5123 | template<move_constructible _Fp, input_range... _Vs> |
5124 | requires (view<_Vs> && ...) && (sizeof...(_Vs) > 0) && is_object_v<_Fp> |
5125 | && regular_invocable<_Fp&, range_reference_t<_Vs>...> |
5126 | && std::__detail::__can_reference<invoke_result_t<_Fp&, range_reference_t<_Vs>...>> |
5127 | template<bool _Const> |
5128 | class zip_transform_view<_Fp, _Vs...>::_Iterator : public __iter_cat<_Const> |
5129 | { |
5130 | using _Parent = __detail::__maybe_const_t<_Const, zip_transform_view>; |
5131 | |
5132 | _Parent* _M_parent = nullptr; |
5133 | __ziperator<_Const> _M_inner; |
5134 | |
5135 | constexpr |
5136 | _Iterator(_Parent& __parent, __ziperator<_Const> __inner) |
5137 | : _M_parent(std::__addressof(__parent)), _M_inner(std::move(__inner)) |
5138 | { } |
5139 | |
5140 | friend class zip_transform_view; |
5141 | |
5142 | public: |
5143 | // iterator_category defined in zip_transform_view::__iter_cat |
5144 | using iterator_concept = typename __ziperator<_Const>::iterator_concept; |
5145 | using value_type |
5146 | = remove_cvref_t<invoke_result_t<__detail::__maybe_const_t<_Const, _Fp>&, |
5147 | range_reference_t<__detail::__maybe_const_t<_Const, _Vs>>...>>; |
5148 | using difference_type = range_difference_t<_Base<_Const>>; |
5149 | |
5150 | _Iterator() = default; |
5151 | |
5152 | constexpr |
5153 | _Iterator(_Iterator<!_Const> __i) |
5154 | requires _Const && convertible_to<__ziperator<false>, __ziperator<_Const>> |
5155 | : _M_parent(__i._M_parent), _M_inner(std::move(__i._M_inner)) |
5156 | { } |
5157 | |
5158 | constexpr decltype(auto) |
5159 | operator*() const |
5160 | { |
5161 | return std::apply([&](const auto&... __iters) -> decltype(auto) { |
5162 | return std::__invoke(*_M_parent->_M_fun, *__iters...); |
5163 | }, _M_inner._M_current); |
5164 | } |
5165 | |
5166 | constexpr _Iterator& |
5167 | operator++() |
5168 | { |
5169 | ++_M_inner; |
5170 | return *this; |
5171 | } |
5172 | |
5173 | constexpr void |
5174 | operator++(int) |
5175 | { ++*this; } |
5176 | |
5177 | constexpr _Iterator |
5178 | operator++(int) requires forward_range<_Base<_Const>> |
5179 | { |
5180 | auto __tmp = *this; |
5181 | ++*this; |
5182 | return __tmp; |
5183 | } |
5184 | |
5185 | constexpr _Iterator& |
5186 | operator--() requires bidirectional_range<_Base<_Const>> |
5187 | { |
5188 | --_M_inner; |
5189 | return *this; |
5190 | } |
5191 | |
5192 | constexpr _Iterator |
5193 | operator--(int) requires bidirectional_range<_Base<_Const>> |
5194 | { |
5195 | auto __tmp = *this; |
5196 | --*this; |
5197 | return __tmp; |
5198 | } |
5199 | |
5200 | constexpr _Iterator& |
5201 | operator+=(difference_type __x) requires random_access_range<_Base<_Const>> |
5202 | { |
5203 | _M_inner += __x; |
5204 | return *this; |
5205 | } |
5206 | |
5207 | constexpr _Iterator& |
5208 | operator-=(difference_type __x) requires random_access_range<_Base<_Const>> |
5209 | { |
5210 | _M_inner -= __x; |
5211 | return *this; |
5212 | } |
5213 | |
5214 | constexpr decltype(auto) |
5215 | operator[](difference_type __n) const requires random_access_range<_Base<_Const>> |
5216 | { |
5217 | return std::apply([&]<typename... _Is>(const _Is&... __iters) -> decltype(auto) { |
5218 | return std::__invoke(*_M_parent->_M_fun, __iters[iter_difference_t<_Is>(__n)]...); |
5219 | }, _M_inner._M_current); |
5220 | } |
5221 | |
5222 | friend constexpr bool |
5223 | operator==(const _Iterator& __x, const _Iterator& __y) |
5224 | requires equality_comparable<__ziperator<_Const>> |
5225 | { return __x._M_inner == __y._M_inner; } |
5226 | |
5227 | friend constexpr auto |
5228 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
5229 | requires random_access_range<_Base<_Const>> |
5230 | { return __x._M_inner <=> __y._M_inner; } |
5231 | |
5232 | friend constexpr _Iterator |
5233 | operator+(const _Iterator& __i, difference_type __n) |
5234 | requires random_access_range<_Base<_Const>> |
5235 | { return _Iterator(*__i._M_parent, __i._M_inner + __n); } |
5236 | |
5237 | friend constexpr _Iterator |
5238 | operator+(difference_type __n, const _Iterator& __i) |
5239 | requires random_access_range<_Base<_Const>> |
5240 | { return _Iterator(*__i._M_parent, __i._M_inner + __n); } |
5241 | |
5242 | friend constexpr _Iterator |
5243 | operator-(const _Iterator& __i, difference_type __n) |
5244 | requires random_access_range<_Base<_Const>> |
5245 | { return _Iterator(*__i._M_parent, __i._M_inner - __n); } |
5246 | |
5247 | friend constexpr difference_type |
5248 | operator-(const _Iterator& __x, const _Iterator& __y) |
5249 | requires sized_sentinel_for<__ziperator<_Const>, __ziperator<_Const>> |
5250 | { return __x._M_inner - __y._M_inner; } |
5251 | }; |
5252 | |
5253 | template<move_constructible _Fp, input_range... _Vs> |
5254 | requires (view<_Vs> && ...) && (sizeof...(_Vs) > 0) && is_object_v<_Fp> |
5255 | && regular_invocable<_Fp&, range_reference_t<_Vs>...> |
5256 | && std::__detail::__can_reference<invoke_result_t<_Fp&, range_reference_t<_Vs>...>> |
5257 | template<bool _Const> |
5258 | class zip_transform_view<_Fp, _Vs...>::_Sentinel |
5259 | { |
5260 | __zentinel<_Const> _M_inner; |
5261 | |
5262 | constexpr explicit |
5263 | _Sentinel(__zentinel<_Const> __inner) |
5264 | : _M_inner(__inner) |
5265 | { } |
5266 | |
5267 | friend class zip_transform_view; |
5268 | |
5269 | public: |
5270 | _Sentinel() = default; |
5271 | |
5272 | constexpr |
5273 | _Sentinel(_Sentinel<!_Const> __i) |
5274 | requires _Const && convertible_to<__zentinel<false>, __zentinel<_Const>> |
5275 | : _M_inner(std::move(__i._M_inner)) |
5276 | { } |
5277 | |
5278 | template<bool _OtherConst> |
5279 | requires sentinel_for<__zentinel<_Const>, __ziperator<_OtherConst>> |
5280 | friend constexpr bool |
5281 | operator==(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
5282 | { return __x._M_inner == __y._M_inner; } |
5283 | |
5284 | template<bool _OtherConst> |
5285 | requires sized_sentinel_for<__zentinel<_Const>, __ziperator<_OtherConst>> |
5286 | friend constexpr range_difference_t<__detail::__maybe_const_t<_OtherConst, _InnerView>> |
5287 | operator-(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
5288 | { return __x._M_inner - __y._M_inner; } |
5289 | |
5290 | template<bool _OtherConst> |
5291 | requires sized_sentinel_for<__zentinel<_Const>, __ziperator<_OtherConst>> |
5292 | friend constexpr range_difference_t<__detail::__maybe_const_t<_OtherConst, _InnerView>> |
5293 | operator-(const _Sentinel& __x, const _Iterator<_OtherConst>& __y) |
5294 | { return __x._M_inner - __y._M_inner; } |
5295 | }; |
5296 | |
5297 | namespace views |
5298 | { |
5299 | namespace __detail |
5300 | { |
5301 | template<typename _Fp, typename... _Ts> |
5302 | concept __can_zip_transform_view |
5303 | = requires { zip_transform_view(std::declval<_Fp>(), std::declval<_Ts>()...); }; |
5304 | } |
5305 | |
5306 | struct _ZipTransform |
5307 | { |
5308 | template<typename _Fp, typename... _Ts> |
5309 | requires (sizeof...(_Ts) == 0) || __detail::__can_zip_transform_view<_Fp, _Ts...> |
5310 | constexpr auto |
5311 | operator() [[nodiscard]] (_Fp&& __f, _Ts&&... __ts) const |
5312 | { |
5313 | if constexpr (sizeof...(_Ts) == 0) |
5314 | return views::empty<decay_t<invoke_result_t<decay_t<_Fp>&>>>; |
5315 | else |
5316 | return zip_transform_view(std::forward<_Fp>(__f), std::forward<_Ts>(__ts)...); |
5317 | } |
5318 | }; |
5319 | |
5320 | inline constexpr _ZipTransform zip_transform; |
5321 | } |
5322 | |
5323 | template<forward_range _Vp, size_t _Nm> |
5324 | requires view<_Vp> && (_Nm > 0) |
5325 | class adjacent_view : public view_interface<adjacent_view<_Vp, _Nm>> |
5326 | { |
5327 | _Vp _M_base = _Vp(); |
5328 | |
5329 | template<bool> class _Iterator; |
5330 | template<bool> class _Sentinel; |
5331 | |
5332 | struct __as_sentinel |
5333 | { }; |
5334 | |
5335 | public: |
5336 | adjacent_view() requires default_initializable<_Vp> = default; |
5337 | |
5338 | constexpr explicit |
5339 | adjacent_view(_Vp __base) |
5340 | : _M_base(std::move(__base)) |
5341 | { } |
5342 | |
5343 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
5344 | // 3848. adjacent_view, adjacent_transform_view and slide_view missing base accessor |
5345 | constexpr _Vp |
5346 | base() const & requires copy_constructible<_Vp> |
5347 | { return _M_base; } |
5348 | |
5349 | constexpr _Vp |
5350 | base() && |
5351 | { return std::move(_M_base); } |
5352 | |
5353 | constexpr auto |
5354 | begin() requires (!__detail::__simple_view<_Vp>) |
5355 | { return _Iterator<false>(ranges::begin(_M_base), ranges::end(_M_base)); } |
5356 | |
5357 | constexpr auto |
5358 | begin() const requires range<const _Vp> |
5359 | { return _Iterator<true>(ranges::begin(_M_base), ranges::end(_M_base)); } |
5360 | |
5361 | constexpr auto |
5362 | end() requires (!__detail::__simple_view<_Vp>) |
5363 | { |
5364 | if constexpr (common_range<_Vp>) |
5365 | return _Iterator<false>(__as_sentinel{}, ranges::begin(_M_base), ranges::end(_M_base)); |
5366 | else |
5367 | return _Sentinel<false>(ranges::end(_M_base)); |
5368 | } |
5369 | |
5370 | constexpr auto |
5371 | end() const requires range<const _Vp> |
5372 | { |
5373 | if constexpr (common_range<const _Vp>) |
5374 | return _Iterator<true>(__as_sentinel{}, ranges::begin(_M_base), ranges::end(_M_base)); |
5375 | else |
5376 | return _Sentinel<true>(ranges::end(_M_base)); |
5377 | } |
5378 | |
5379 | constexpr auto |
5380 | size() requires sized_range<_Vp> |
5381 | { |
5382 | using _ST = decltype(ranges::size(_M_base)); |
5383 | using _CT = common_type_t<_ST, size_t>; |
5384 | auto __sz = static_cast<_CT>(ranges::size(_M_base)); |
5385 | __sz -= std::min<_CT>(__sz, _Nm - 1); |
5386 | return static_cast<_ST>(__sz); |
5387 | } |
5388 | |
5389 | constexpr auto |
5390 | size() const requires sized_range<const _Vp> |
5391 | { |
5392 | using _ST = decltype(ranges::size(_M_base)); |
5393 | using _CT = common_type_t<_ST, size_t>; |
5394 | auto __sz = static_cast<_CT>(ranges::size(_M_base)); |
5395 | __sz -= std::min<_CT>(__sz, _Nm - 1); |
5396 | return static_cast<_ST>(__sz); |
5397 | } |
5398 | }; |
5399 | |
5400 | template<typename _Vp, size_t _Nm> |
5401 | inline constexpr bool enable_borrowed_range<adjacent_view<_Vp, _Nm>> |
5402 | = enable_borrowed_range<_Vp>; |
5403 | |
5404 | namespace __detail |
5405 | { |
5406 | // Yields tuple<_Tp, ..., _Tp> with _Nm elements. |
5407 | template<typename _Tp, size_t _Nm> |
5408 | using __repeated_tuple = decltype(std::tuple_cat(std::declval<array<_Tp, _Nm>>())); |
5409 | |
5410 | // For a functor F that is callable with N arguments, the expression |
5411 | // declval<__unarize<F, N>>(x) is equivalent to declval<F>(x, ..., x). |
5412 | template<typename _Fp, size_t _Nm> |
5413 | struct __unarize |
5414 | { |
5415 | template<typename... _Ts> |
5416 | static invoke_result_t<_Fp, _Ts...> |
5417 | __tuple_apply(const tuple<_Ts...>&); // not defined |
5418 | |
5419 | template<typename _Tp> |
5420 | decltype(__tuple_apply(std::declval<__repeated_tuple<_Tp, _Nm>>())) |
5421 | operator()(_Tp&&); // not defined |
5422 | }; |
5423 | } |
5424 | |
5425 | template<forward_range _Vp, size_t _Nm> |
5426 | requires view<_Vp> && (_Nm > 0) |
5427 | template<bool _Const> |
5428 | class adjacent_view<_Vp, _Nm>::_Iterator |
5429 | { |
5430 | #ifdef __clang__ // LLVM-61763 workaround |
5431 | public: |
5432 | #endif |
5433 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
5434 | array<iterator_t<_Base>, _Nm> _M_current = array<iterator_t<_Base>, _Nm>(); |
5435 | |
5436 | constexpr |
5437 | _Iterator(iterator_t<_Base> __first, sentinel_t<_Base> __last) |
5438 | { |
5439 | for (auto& __i : _M_current) |
5440 | { |
5441 | __i = __first; |
5442 | ranges::advance(__first, 1, __last); |
5443 | } |
5444 | } |
5445 | |
5446 | constexpr |
5447 | _Iterator(__as_sentinel, iterator_t<_Base> __first, iterator_t<_Base> __last) |
5448 | { |
5449 | if constexpr (!bidirectional_range<_Base>) |
5450 | for (auto& __it : _M_current) |
5451 | __it = __last; |
5452 | else |
5453 | for (size_t __i = 0; __i < _Nm; ++__i) |
5454 | { |
5455 | _M_current[_Nm - 1 - __i] = __last; |
5456 | ranges::advance(__last, -1, __first); |
5457 | } |
5458 | } |
5459 | |
5460 | static auto |
5461 | _S_iter_concept() |
5462 | { |
5463 | if constexpr (random_access_range<_Base>) |
5464 | return random_access_iterator_tag{}; |
5465 | else if constexpr (bidirectional_range<_Base>) |
5466 | return bidirectional_iterator_tag{}; |
5467 | else |
5468 | return forward_iterator_tag{}; |
5469 | } |
5470 | |
5471 | friend class adjacent_view; |
5472 | |
5473 | #ifndef __clang__ // LLVM-61763 workaround |
5474 | template<forward_range _Wp, move_constructible _Fp, size_t _Mm> |
5475 | requires view<_Wp> && (_Mm > 0) && is_object_v<_Fp> |
5476 | && regular_invocable<__detail::__unarize<_Fp&, _Mm>, range_reference_t<_Wp>> |
5477 | && std::__detail::__can_reference<invoke_result_t<__detail::__unarize<_Fp&, _Mm>, |
5478 | range_reference_t<_Wp>>> |
5479 | friend class adjacent_transform_view; |
5480 | #endif |
5481 | |
5482 | public: |
5483 | using iterator_category = input_iterator_tag; |
5484 | using iterator_concept = decltype(_S_iter_concept()); |
5485 | using value_type = conditional_t<_Nm == 2, |
5486 | pair<range_value_t<_Base>, range_value_t<_Base>>, |
5487 | __detail::__repeated_tuple<range_value_t<_Base>, _Nm>>; |
5488 | using difference_type = range_difference_t<_Base>; |
5489 | |
5490 | _Iterator() = default; |
5491 | |
5492 | constexpr |
5493 | _Iterator(_Iterator<!_Const> __i) |
5494 | requires _Const && convertible_to<iterator_t<_Vp>, iterator_t<_Base>> |
5495 | { |
5496 | for (size_t __j = 0; __j < _Nm; ++__j) |
5497 | _M_current[__j] = std::move(__i._M_current[__j]); |
5498 | } |
5499 | |
5500 | constexpr auto |
5501 | operator*() const |
5502 | { |
5503 | auto __f = [](auto& __i) -> decltype(auto) { return *__i; }; |
5504 | return __detail::__tuple_transform(__f, _M_current); |
5505 | } |
5506 | |
5507 | constexpr _Iterator& |
5508 | operator++() |
5509 | { |
5510 | for (auto& __i : _M_current) |
5511 | ++__i; |
5512 | return *this; |
5513 | } |
5514 | |
5515 | constexpr _Iterator |
5516 | operator++(int) |
5517 | { |
5518 | auto __tmp = *this; |
5519 | ++*this; |
5520 | return __tmp; |
5521 | } |
5522 | |
5523 | constexpr _Iterator& |
5524 | operator--() requires bidirectional_range<_Base> |
5525 | { |
5526 | for (auto& __i : _M_current) |
5527 | --__i; |
5528 | return *this; |
5529 | } |
5530 | |
5531 | constexpr _Iterator |
5532 | operator--(int) requires bidirectional_range<_Base> |
5533 | { |
5534 | auto __tmp = *this; |
5535 | --*this; |
5536 | return __tmp; |
5537 | } |
5538 | |
5539 | constexpr _Iterator& |
5540 | operator+=(difference_type __x) |
5541 | requires random_access_range<_Base> |
5542 | { |
5543 | for (auto& __i : _M_current) |
5544 | __i += __x; |
5545 | return *this; |
5546 | } |
5547 | |
5548 | constexpr _Iterator& |
5549 | operator-=(difference_type __x) |
5550 | requires random_access_range<_Base> |
5551 | { |
5552 | for (auto& __i : _M_current) |
5553 | __i -= __x; |
5554 | return *this; |
5555 | } |
5556 | |
5557 | constexpr auto |
5558 | operator[](difference_type __n) const |
5559 | requires random_access_range<_Base> |
5560 | { |
5561 | auto __f = [&](auto& __i) -> decltype(auto) { return __i[__n]; }; |
5562 | return __detail::__tuple_transform(__f, _M_current); |
5563 | } |
5564 | |
5565 | friend constexpr bool |
5566 | operator==(const _Iterator& __x, const _Iterator& __y) |
5567 | { return __x._M_current.back() == __y._M_current.back(); } |
5568 | |
5569 | friend constexpr bool |
5570 | operator<(const _Iterator& __x, const _Iterator& __y) |
5571 | requires random_access_range<_Base> |
5572 | { return __x._M_current.back() < __y._M_current.back(); } |
5573 | |
5574 | friend constexpr bool |
5575 | operator>(const _Iterator& __x, const _Iterator& __y) |
5576 | requires random_access_range<_Base> |
5577 | { return __y < __x; } |
5578 | |
5579 | friend constexpr bool |
5580 | operator<=(const _Iterator& __x, const _Iterator& __y) |
5581 | requires random_access_range<_Base> |
5582 | { return !(__y < __x); } |
5583 | |
5584 | friend constexpr bool |
5585 | operator>=(const _Iterator& __x, const _Iterator& __y) |
5586 | requires random_access_range<_Base> |
5587 | { return !(__x < __y); } |
5588 | |
5589 | friend constexpr auto |
5590 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
5591 | requires random_access_range<_Base> |
5592 | && three_way_comparable<iterator_t<_Base>> |
5593 | { return __x._M_current.back() <=> __y._M_current.back(); } |
5594 | |
5595 | friend constexpr _Iterator |
5596 | operator+(const _Iterator& __i, difference_type __n) |
5597 | requires random_access_range<_Base> |
5598 | { |
5599 | auto __r = __i; |
5600 | __r += __n; |
5601 | return __r; |
5602 | } |
5603 | |
5604 | friend constexpr _Iterator |
5605 | operator+(difference_type __n, const _Iterator& __i) |
5606 | requires random_access_range<_Base> |
5607 | { |
5608 | auto __r = __i; |
5609 | __r += __n; |
5610 | return __r; |
5611 | } |
5612 | |
5613 | friend constexpr _Iterator |
5614 | operator-(const _Iterator& __i, difference_type __n) |
5615 | requires random_access_range<_Base> |
5616 | { |
5617 | auto __r = __i; |
5618 | __r -= __n; |
5619 | return __r; |
5620 | } |
5621 | |
5622 | friend constexpr difference_type |
5623 | operator-(const _Iterator& __x, const _Iterator& __y) |
5624 | requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>> |
5625 | { return __x._M_current.back() - __y._M_current.back(); } |
5626 | |
5627 | friend constexpr auto |
5628 | iter_move(const _Iterator& __i) |
5629 | { return __detail::__tuple_transform(ranges::iter_move, __i._M_current); } |
5630 | |
5631 | friend constexpr void |
5632 | iter_swap(const _Iterator& __l, const _Iterator& __r) |
5633 | requires indirectly_swappable<iterator_t<_Base>> |
5634 | { |
5635 | for (size_t __i = 0; __i < _Nm; __i++) |
5636 | ranges::iter_swap(__l._M_current[__i], __r._M_current[__i]); |
5637 | } |
5638 | }; |
5639 | |
5640 | template<forward_range _Vp, size_t _Nm> |
5641 | requires view<_Vp> && (_Nm > 0) |
5642 | template<bool _Const> |
5643 | class adjacent_view<_Vp, _Nm>::_Sentinel |
5644 | { |
5645 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
5646 | |
5647 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
5648 | |
5649 | constexpr explicit |
5650 | _Sentinel(sentinel_t<_Base> __end) |
5651 | : _M_end(__end) |
5652 | { } |
5653 | |
5654 | friend class adjacent_view; |
5655 | |
5656 | public: |
5657 | _Sentinel() = default; |
5658 | |
5659 | constexpr |
5660 | _Sentinel(_Sentinel<!_Const> __i) |
5661 | requires _Const && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
5662 | : _M_end(std::move(__i._M_end)) |
5663 | { } |
5664 | |
5665 | template<bool _OtherConst> |
5666 | requires sentinel_for<sentinel_t<_Base>, |
5667 | iterator_t<__detail::__maybe_const_t<_OtherConst, _Vp>>> |
5668 | friend constexpr bool |
5669 | operator==(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
5670 | { return __x._M_current.back() == __y._M_end; } |
5671 | |
5672 | template<bool _OtherConst> |
5673 | requires sized_sentinel_for<sentinel_t<_Base>, |
5674 | iterator_t<__detail::__maybe_const_t<_OtherConst, _Vp>>> |
5675 | friend constexpr range_difference_t<__detail::__maybe_const_t<_OtherConst, _Vp>> |
5676 | operator-(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
5677 | { return __x._M_current.back() - __y._M_end; } |
5678 | |
5679 | template<bool _OtherConst> |
5680 | requires sized_sentinel_for<sentinel_t<_Base>, |
5681 | iterator_t<__detail::__maybe_const_t<_OtherConst, _Vp>>> |
5682 | friend constexpr range_difference_t<__detail::__maybe_const_t<_OtherConst, _Vp>> |
5683 | operator-(const _Sentinel& __y, const _Iterator<_OtherConst>& __x) |
5684 | { return __y._M_end - __x._M_current.back(); } |
5685 | }; |
5686 | |
5687 | namespace views |
5688 | { |
5689 | namespace __detail |
5690 | { |
5691 | template<size_t _Nm, typename _Range> |
5692 | concept __can_adjacent_view |
5693 | = requires { adjacent_view<all_t<_Range>, _Nm>(std::declval<_Range>()); }; |
5694 | } |
5695 | |
5696 | template<size_t _Nm> |
5697 | struct _Adjacent : __adaptor::_RangeAdaptorClosure<_Adjacent<_Nm>> |
5698 | { |
5699 | template<viewable_range _Range> |
5700 | requires (_Nm == 0) || __detail::__can_adjacent_view<_Nm, _Range> |
5701 | constexpr auto |
5702 | operator() [[nodiscard]] (_Range&& __r) const |
5703 | { |
5704 | if constexpr (_Nm == 0) |
5705 | return views::empty<tuple<>>; |
5706 | else |
5707 | return adjacent_view<all_t<_Range>, _Nm>(std::forward<_Range>(__r)); |
5708 | } |
5709 | }; |
5710 | |
5711 | template<size_t _Nm> |
5712 | inline constexpr _Adjacent<_Nm> adjacent; |
5713 | |
5714 | inline constexpr auto pairwise = adjacent<2>; |
5715 | } |
5716 | |
5717 | template<forward_range _Vp, move_constructible _Fp, size_t _Nm> |
5718 | requires view<_Vp> && (_Nm > 0) && is_object_v<_Fp> |
5719 | && regular_invocable<__detail::__unarize<_Fp&, _Nm>, range_reference_t<_Vp>> |
5720 | && std::__detail::__can_reference<invoke_result_t<__detail::__unarize<_Fp&, _Nm>, |
5721 | range_reference_t<_Vp>>> |
5722 | class adjacent_transform_view : public view_interface<adjacent_transform_view<_Vp, _Fp, _Nm>> |
5723 | { |
5724 | [[no_unique_address]] __detail::__box<_Fp> _M_fun; |
5725 | adjacent_view<_Vp, _Nm> _M_inner; |
5726 | |
5727 | using _InnerView = adjacent_view<_Vp, _Nm>; |
5728 | |
5729 | template<bool _Const> |
5730 | using _InnerIter = iterator_t<__detail::__maybe_const_t<_Const, _InnerView>>; |
5731 | |
5732 | template<bool _Const> |
5733 | using _InnerSent = sentinel_t<__detail::__maybe_const_t<_Const, _InnerView>>; |
5734 | |
5735 | template<bool> class _Iterator; |
5736 | template<bool> class _Sentinel; |
5737 | |
5738 | public: |
5739 | adjacent_transform_view() = default; |
5740 | |
5741 | constexpr explicit |
5742 | adjacent_transform_view(_Vp __base, _Fp __fun) |
5743 | : _M_fun(std::move(__fun)), _M_inner(std::move(__base)) |
5744 | { } |
5745 | |
5746 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
5747 | // 3848. adjacent_view, adjacent_transform_view and slide_view missing base accessor |
5748 | // 3947. Unexpected constraints on adjacent_transform_view::base() |
5749 | constexpr _Vp |
5750 | base() const & requires copy_constructible<_Vp> |
5751 | { return _M_inner.base(); } |
5752 | |
5753 | constexpr _Vp |
5754 | base() && |
5755 | { return std::move(_M_inner.base()); } |
5756 | |
5757 | constexpr auto |
5758 | begin() |
5759 | { return _Iterator<false>(*this, _M_inner.begin()); } |
5760 | |
5761 | constexpr auto |
5762 | begin() const |
5763 | requires range<const _InnerView> |
5764 | && regular_invocable<__detail::__unarize<const _Fp&, _Nm>, |
5765 | range_reference_t<const _Vp>> |
5766 | { return _Iterator<true>(*this, _M_inner.begin()); } |
5767 | |
5768 | constexpr auto |
5769 | end() |
5770 | { |
5771 | if constexpr (common_range<_InnerView>) |
5772 | return _Iterator<false>(*this, _M_inner.end()); |
5773 | else |
5774 | return _Sentinel<false>(_M_inner.end()); |
5775 | } |
5776 | |
5777 | constexpr auto |
5778 | end() const |
5779 | requires range<const _InnerView> |
5780 | && regular_invocable<__detail::__unarize<const _Fp&, _Nm>, |
5781 | range_reference_t<const _Vp>> |
5782 | { |
5783 | if constexpr (common_range<const _InnerView>) |
5784 | return _Iterator<true>(*this, _M_inner.end()); |
5785 | else |
5786 | return _Sentinel<true>(_M_inner.end()); |
5787 | } |
5788 | |
5789 | constexpr auto |
5790 | size() requires sized_range<_InnerView> |
5791 | { return _M_inner.size(); } |
5792 | |
5793 | constexpr auto |
5794 | size() const requires sized_range<const _InnerView> |
5795 | { return _M_inner.size(); } |
5796 | }; |
5797 | |
5798 | template<forward_range _Vp, move_constructible _Fp, size_t _Nm> |
5799 | requires view<_Vp> && (_Nm > 0) && is_object_v<_Fp> |
5800 | && regular_invocable<__detail::__unarize<_Fp&, _Nm>, range_reference_t<_Vp>> |
5801 | && std::__detail::__can_reference<invoke_result_t<__detail::__unarize<_Fp&, _Nm>, |
5802 | range_reference_t<_Vp>>> |
5803 | template<bool _Const> |
5804 | class adjacent_transform_view<_Vp, _Fp, _Nm>::_Iterator |
5805 | { |
5806 | using _Parent = __detail::__maybe_const_t<_Const, adjacent_transform_view>; |
5807 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
5808 | |
5809 | _Parent* _M_parent = nullptr; |
5810 | _InnerIter<_Const> _M_inner; |
5811 | |
5812 | constexpr |
5813 | _Iterator(_Parent& __parent, _InnerIter<_Const> __inner) |
5814 | : _M_parent(std::__addressof(__parent)), _M_inner(std::move(__inner)) |
5815 | { } |
5816 | |
5817 | static auto |
5818 | _S_iter_cat() |
5819 | { |
5820 | using __detail::__maybe_const_t; |
5821 | using __detail::__unarize; |
5822 | using _Res = invoke_result_t<__unarize<__maybe_const_t<_Const, _Fp>&, _Nm>, |
5823 | range_reference_t<_Base>>; |
5824 | using _Cat = typename iterator_traits<iterator_t<_Base>>::iterator_category; |
5825 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
5826 | // 3798. Rvalue reference and iterator_category |
5827 | if constexpr (!is_reference_v<_Res>) |
5828 | return input_iterator_tag{}; |
5829 | else if constexpr (derived_from<_Cat, random_access_iterator_tag>) |
5830 | return random_access_iterator_tag{}; |
5831 | else if constexpr (derived_from<_Cat, bidirectional_iterator_tag>) |
5832 | return bidirectional_iterator_tag{}; |
5833 | else if constexpr (derived_from<_Cat, forward_iterator_tag>) |
5834 | return forward_iterator_tag{}; |
5835 | else |
5836 | return input_iterator_tag{}; |
5837 | } |
5838 | |
5839 | friend class adjacent_transform_view; |
5840 | |
5841 | public: |
5842 | using iterator_category = decltype(_S_iter_cat()); |
5843 | using iterator_concept = typename _InnerIter<_Const>::iterator_concept; |
5844 | using value_type |
5845 | = remove_cvref_t<invoke_result_t |
5846 | <__detail::__unarize<__detail::__maybe_const_t<_Const, _Fp>&, _Nm>, |
5847 | range_reference_t<_Base>>>; |
5848 | using difference_type = range_difference_t<_Base>; |
5849 | |
5850 | _Iterator() = default; |
5851 | |
5852 | constexpr |
5853 | _Iterator(_Iterator<!_Const> __i) |
5854 | requires _Const && convertible_to<_InnerIter<false>, _InnerIter<_Const>> |
5855 | : _M_parent(__i._M_parent), _M_inner(std::move(__i._M_inner)) |
5856 | { } |
5857 | |
5858 | constexpr decltype(auto) |
5859 | operator*() const |
5860 | { |
5861 | return std::apply([&](const auto&... __iters) -> decltype(auto) { |
5862 | return std::__invoke(*_M_parent->_M_fun, *__iters...); |
5863 | }, _M_inner._M_current); |
5864 | } |
5865 | |
5866 | constexpr _Iterator& |
5867 | operator++() |
5868 | { |
5869 | ++_M_inner; |
5870 | return *this; |
5871 | } |
5872 | |
5873 | constexpr _Iterator |
5874 | operator++(int) |
5875 | { |
5876 | auto __tmp = *this; |
5877 | ++*this; |
5878 | return __tmp; |
5879 | } |
5880 | |
5881 | constexpr _Iterator& |
5882 | operator--() requires bidirectional_range<_Base> |
5883 | { |
5884 | --_M_inner; |
5885 | return *this; |
5886 | } |
5887 | |
5888 | constexpr _Iterator |
5889 | operator--(int) requires bidirectional_range<_Base> |
5890 | { |
5891 | auto __tmp = *this; |
5892 | --*this; |
5893 | return __tmp; |
5894 | } |
5895 | |
5896 | constexpr _Iterator& |
5897 | operator+=(difference_type __x) requires random_access_range<_Base> |
5898 | { |
5899 | _M_inner += __x; |
5900 | return *this; |
5901 | } |
5902 | |
5903 | constexpr _Iterator& |
5904 | operator-=(difference_type __x) requires random_access_range<_Base> |
5905 | { |
5906 | _M_inner -= __x; |
5907 | return *this; |
5908 | } |
5909 | |
5910 | constexpr decltype(auto) |
5911 | operator[](difference_type __n) const requires random_access_range<_Base> |
5912 | { |
5913 | return std::apply([&](const auto&... __iters) -> decltype(auto) { |
5914 | return std::__invoke(*_M_parent->_M_fun, __iters[__n]...); |
5915 | }, _M_inner._M_current); |
5916 | } |
5917 | |
5918 | friend constexpr bool |
5919 | operator==(const _Iterator& __x, const _Iterator& __y) |
5920 | { return __x._M_inner == __y._M_inner; } |
5921 | |
5922 | friend constexpr bool |
5923 | operator<(const _Iterator& __x, const _Iterator& __y) |
5924 | requires random_access_range<_Base> |
5925 | { return __x._M_inner < __y._M_inner; } |
5926 | |
5927 | friend constexpr bool |
5928 | operator>(const _Iterator& __x, const _Iterator& __y) |
5929 | requires random_access_range<_Base> |
5930 | { return __x._M_inner > __y._M_inner; } |
5931 | |
5932 | friend constexpr bool |
5933 | operator<=(const _Iterator& __x, const _Iterator& __y) |
5934 | requires random_access_range<_Base> |
5935 | { return __x._M_inner <= __y._M_inner; } |
5936 | |
5937 | friend constexpr bool |
5938 | operator>=(const _Iterator& __x, const _Iterator& __y) |
5939 | requires random_access_range<_Base> |
5940 | { return __x._M_inner >= __y._M_inner; } |
5941 | |
5942 | friend constexpr auto |
5943 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
5944 | requires random_access_range<_Base> && |
5945 | three_way_comparable<_InnerIter<_Const>> |
5946 | { return __x._M_inner <=> __y._M_inner; } |
5947 | |
5948 | friend constexpr _Iterator |
5949 | operator+(const _Iterator& __i, difference_type __n) |
5950 | requires random_access_range<_Base> |
5951 | { return _Iterator(*__i._M_parent, __i._M_inner + __n); } |
5952 | |
5953 | friend constexpr _Iterator |
5954 | operator+(difference_type __n, const _Iterator& __i) |
5955 | requires random_access_range<_Base> |
5956 | { return _Iterator(*__i._M_parent, __i._M_inner + __n); } |
5957 | |
5958 | friend constexpr _Iterator |
5959 | operator-(const _Iterator& __i, difference_type __n) |
5960 | requires random_access_range<_Base> |
5961 | { return _Iterator(*__i._M_parent, __i._M_inner - __n); } |
5962 | |
5963 | friend constexpr difference_type |
5964 | operator-(const _Iterator& __x, const _Iterator& __y) |
5965 | requires sized_sentinel_for<_InnerIter<_Const>, _InnerIter<_Const>> |
5966 | { return __x._M_inner - __y._M_inner; } |
5967 | }; |
5968 | |
5969 | template<forward_range _Vp, move_constructible _Fp, size_t _Nm> |
5970 | requires view<_Vp> && (_Nm > 0) && is_object_v<_Fp> |
5971 | && regular_invocable<__detail::__unarize<_Fp&, _Nm>, range_reference_t<_Vp>> |
5972 | && std::__detail::__can_reference<invoke_result_t<__detail::__unarize<_Fp&, _Nm>, |
5973 | range_reference_t<_Vp>>> |
5974 | template<bool _Const> |
5975 | class adjacent_transform_view<_Vp, _Fp, _Nm>::_Sentinel |
5976 | { |
5977 | _InnerSent<_Const> _M_inner; |
5978 | |
5979 | constexpr explicit |
5980 | _Sentinel(_InnerSent<_Const> __inner) |
5981 | : _M_inner(__inner) |
5982 | { } |
5983 | |
5984 | friend class adjacent_transform_view; |
5985 | |
5986 | public: |
5987 | _Sentinel() = default; |
5988 | |
5989 | constexpr |
5990 | _Sentinel(_Sentinel<!_Const> __i) |
5991 | requires _Const && convertible_to<_InnerSent<false>, _InnerSent<_Const>> |
5992 | : _M_inner(std::move(__i._M_inner)) |
5993 | { } |
5994 | |
5995 | template<bool _OtherConst> |
5996 | requires sentinel_for<_InnerSent<_Const>, _InnerIter<_OtherConst>> |
5997 | friend constexpr bool |
5998 | operator==(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
5999 | { return __x._M_inner == __y._M_inner; } |
6000 | |
6001 | template<bool _OtherConst> |
6002 | requires sized_sentinel_for<_InnerSent<_Const>, _InnerIter<_OtherConst>> |
6003 | friend constexpr range_difference_t<__detail::__maybe_const_t<_OtherConst, _InnerView>> |
6004 | operator-(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
6005 | { return __x._M_inner - __y._M_inner; } |
6006 | |
6007 | template<bool _OtherConst> |
6008 | requires sized_sentinel_for<_InnerSent<_Const>, _InnerIter<_OtherConst>> |
6009 | friend constexpr range_difference_t<__detail::__maybe_const_t<_OtherConst, _InnerView>> |
6010 | operator-(const _Sentinel& __x, const _Iterator<_OtherConst>& __y) |
6011 | { return __x._M_inner - __y._M_inner; } |
6012 | }; |
6013 | |
6014 | namespace views |
6015 | { |
6016 | namespace __detail |
6017 | { |
6018 | template<size_t _Nm, typename _Range, typename _Fp> |
6019 | concept __can_adjacent_transform_view |
6020 | = requires { adjacent_transform_view<all_t<_Range>, decay_t<_Fp>, _Nm> |
6021 | (std::declval<_Range>(), std::declval<_Fp>()); }; |
6022 | } |
6023 | |
6024 | template<size_t _Nm> |
6025 | struct _AdjacentTransform : __adaptor::_RangeAdaptor<_AdjacentTransform<_Nm>> |
6026 | { |
6027 | template<viewable_range _Range, typename _Fp> |
6028 | requires (_Nm == 0) || __detail::__can_adjacent_transform_view<_Nm, _Range, _Fp> |
6029 | constexpr auto |
6030 | operator() [[nodiscard]] (_Range&& __r, _Fp&& __f) const |
6031 | { |
6032 | if constexpr (_Nm == 0) |
6033 | return zip_transform(std::forward<_Fp>(__f)); |
6034 | else |
6035 | return adjacent_transform_view<all_t<_Range>, decay_t<_Fp>, _Nm> |
6036 | (std::forward<_Range>(__r), std::forward<_Fp>(__f)); |
6037 | } |
6038 | |
6039 | using __adaptor::_RangeAdaptor<_AdjacentTransform>::operator(); |
6040 | static constexpr int _S_arity = 2; |
6041 | static constexpr bool = true; |
6042 | }; |
6043 | |
6044 | template<size_t _Nm> |
6045 | inline constexpr _AdjacentTransform<_Nm> adjacent_transform; |
6046 | |
6047 | inline constexpr auto pairwise_transform = adjacent_transform<2>; |
6048 | } |
6049 | #endif // __cpp_lib_ranges_zip |
6050 | |
6051 | #ifdef __cpp_lib_ranges_chunk // C++ >= 23 |
6052 | namespace __detail |
6053 | { |
6054 | template<typename _Tp> |
6055 | constexpr _Tp __div_ceil(_Tp __num, _Tp __denom) |
6056 | { |
6057 | _Tp __r = __num / __denom; |
6058 | if (__num % __denom) |
6059 | ++__r; |
6060 | return __r; |
6061 | } |
6062 | } |
6063 | |
6064 | template<view _Vp> |
6065 | requires input_range<_Vp> |
6066 | class chunk_view : public view_interface<chunk_view<_Vp>> |
6067 | { |
6068 | _Vp _M_base; |
6069 | range_difference_t<_Vp> _M_n; |
6070 | range_difference_t<_Vp> _M_remainder = 0; |
6071 | __detail::__non_propagating_cache<iterator_t<_Vp>> _M_current; |
6072 | |
6073 | class _OuterIter; |
6074 | class _InnerIter; |
6075 | |
6076 | public: |
6077 | constexpr explicit |
6078 | chunk_view(_Vp __base, range_difference_t<_Vp> __n) |
6079 | : _M_base(std::move(__base)), _M_n(__n) |
6080 | { __glibcxx_assert(__n >= 0); } |
6081 | |
6082 | constexpr _Vp |
6083 | base() const & requires copy_constructible<_Vp> |
6084 | { return _M_base; } |
6085 | |
6086 | constexpr _Vp |
6087 | base() && |
6088 | { return std::move(_M_base); } |
6089 | |
6090 | constexpr _OuterIter |
6091 | begin() |
6092 | { |
6093 | _M_current = ranges::begin(_M_base); |
6094 | _M_remainder = _M_n; |
6095 | return _OuterIter(*this); |
6096 | } |
6097 | |
6098 | constexpr default_sentinel_t |
6099 | end() const noexcept |
6100 | { return default_sentinel; } |
6101 | |
6102 | constexpr auto |
6103 | size() requires sized_range<_Vp> |
6104 | { |
6105 | return __detail::__to_unsigned_like(__detail::__div_ceil |
6106 | (ranges::distance(_M_base), _M_n)); |
6107 | } |
6108 | |
6109 | constexpr auto |
6110 | size() const requires sized_range<const _Vp> |
6111 | { |
6112 | return __detail::__to_unsigned_like(__detail::__div_ceil |
6113 | (ranges::distance(_M_base), _M_n)); |
6114 | } |
6115 | }; |
6116 | |
6117 | template<typename _Range> |
6118 | chunk_view(_Range&&, range_difference_t<_Range>) -> chunk_view<views::all_t<_Range>>; |
6119 | |
6120 | template<view _Vp> |
6121 | requires input_range<_Vp> |
6122 | class chunk_view<_Vp>::_OuterIter |
6123 | { |
6124 | chunk_view* _M_parent; |
6125 | |
6126 | constexpr explicit |
6127 | _OuterIter(chunk_view& __parent) noexcept |
6128 | : _M_parent(std::__addressof(__parent)) |
6129 | { } |
6130 | |
6131 | friend chunk_view; |
6132 | |
6133 | public: |
6134 | using iterator_concept = input_iterator_tag; |
6135 | using difference_type = range_difference_t<_Vp>; |
6136 | |
6137 | struct value_type; |
6138 | |
6139 | _OuterIter(_OuterIter&&) = default; |
6140 | _OuterIter& operator=(_OuterIter&&) = default; |
6141 | |
6142 | constexpr value_type |
6143 | operator*() const |
6144 | { |
6145 | __glibcxx_assert(*this != default_sentinel); |
6146 | return value_type(*_M_parent); |
6147 | } |
6148 | |
6149 | constexpr _OuterIter& |
6150 | operator++() |
6151 | { |
6152 | __glibcxx_assert(*this != default_sentinel); |
6153 | ranges::advance(*_M_parent->_M_current, _M_parent->_M_remainder, |
6154 | ranges::end(_M_parent->_M_base)); |
6155 | _M_parent->_M_remainder = _M_parent->_M_n; |
6156 | return *this; |
6157 | } |
6158 | |
6159 | constexpr void |
6160 | operator++(int) |
6161 | { ++*this; } |
6162 | |
6163 | friend constexpr bool |
6164 | operator==(const _OuterIter& __x, default_sentinel_t) |
6165 | { |
6166 | return *__x._M_parent->_M_current == ranges::end(__x._M_parent->_M_base) |
6167 | && __x._M_parent->_M_remainder != 0; |
6168 | } |
6169 | |
6170 | friend constexpr difference_type |
6171 | operator-(default_sentinel_t, const _OuterIter& __x) |
6172 | requires sized_sentinel_for<sentinel_t<_Vp>, iterator_t<_Vp>> |
6173 | { |
6174 | const auto __dist = ranges::end(__x._M_parent->_M_base) - *__x._M_parent->_M_current; |
6175 | |
6176 | if (__dist < __x._M_parent->_M_remainder) |
6177 | return __dist == 0 ? 0 : 1; |
6178 | |
6179 | return 1 + __detail::__div_ceil(__dist - __x._M_parent->_M_remainder, |
6180 | __x._M_parent->_M_n); |
6181 | } |
6182 | |
6183 | friend constexpr difference_type |
6184 | operator-(const _OuterIter& __x, default_sentinel_t __y) |
6185 | requires sized_sentinel_for<sentinel_t<_Vp>, iterator_t<_Vp>> |
6186 | { return -(__y - __x); } |
6187 | }; |
6188 | |
6189 | template<view _Vp> |
6190 | requires input_range<_Vp> |
6191 | struct chunk_view<_Vp>::_OuterIter::value_type : view_interface<value_type> |
6192 | { |
6193 | private: |
6194 | chunk_view* _M_parent; |
6195 | |
6196 | constexpr explicit |
6197 | value_type(chunk_view& __parent) noexcept |
6198 | : _M_parent(std::__addressof(__parent)) |
6199 | { } |
6200 | |
6201 | friend _OuterIter; |
6202 | |
6203 | public: |
6204 | constexpr _InnerIter |
6205 | begin() const noexcept |
6206 | { return _InnerIter(*_M_parent); } |
6207 | |
6208 | constexpr default_sentinel_t |
6209 | end() const noexcept |
6210 | { return default_sentinel; } |
6211 | |
6212 | constexpr auto |
6213 | size() const |
6214 | requires sized_sentinel_for<sentinel_t<_Vp>, iterator_t<_Vp>> |
6215 | { |
6216 | return __detail::__to_unsigned_like |
6217 | (ranges::min(_M_parent->_M_remainder, |
6218 | ranges::end(_M_parent->_M_base) - *_M_parent->_M_current)); |
6219 | } |
6220 | }; |
6221 | |
6222 | template<view _Vp> |
6223 | requires input_range<_Vp> |
6224 | class chunk_view<_Vp>::_InnerIter |
6225 | { |
6226 | chunk_view* _M_parent; |
6227 | |
6228 | constexpr explicit |
6229 | _InnerIter(chunk_view& __parent) noexcept |
6230 | : _M_parent(std::__addressof(__parent)) |
6231 | { } |
6232 | |
6233 | friend _OuterIter::value_type; |
6234 | |
6235 | public: |
6236 | using iterator_concept = input_iterator_tag; |
6237 | using difference_type = range_difference_t<_Vp>; |
6238 | using value_type = range_value_t<_Vp>; |
6239 | |
6240 | _InnerIter(_InnerIter&&) = default; |
6241 | _InnerIter& operator=(_InnerIter&&) = default; |
6242 | |
6243 | constexpr const iterator_t<_Vp>& |
6244 | base() const & |
6245 | { return *_M_parent->_M_current; } |
6246 | |
6247 | constexpr range_reference_t<_Vp> |
6248 | operator*() const |
6249 | { |
6250 | __glibcxx_assert(*this != default_sentinel); |
6251 | return **_M_parent->_M_current; |
6252 | } |
6253 | |
6254 | constexpr _InnerIter& |
6255 | operator++() |
6256 | { |
6257 | __glibcxx_assert(*this != default_sentinel); |
6258 | ++*_M_parent->_M_current; |
6259 | if (*_M_parent->_M_current == ranges::end(_M_parent->_M_base)) |
6260 | _M_parent->_M_remainder = 0; |
6261 | else |
6262 | --_M_parent->_M_remainder; |
6263 | return *this; |
6264 | } |
6265 | |
6266 | constexpr void |
6267 | operator++(int) |
6268 | { ++*this; } |
6269 | |
6270 | friend constexpr bool |
6271 | operator==(const _InnerIter& __x, default_sentinel_t) noexcept |
6272 | { return __x._M_parent->_M_remainder == 0; } |
6273 | |
6274 | friend constexpr difference_type |
6275 | operator-(default_sentinel_t, const _InnerIter& __x) |
6276 | requires sized_sentinel_for<sentinel_t<_Vp>, iterator_t<_Vp>> |
6277 | { |
6278 | return ranges::min(__x._M_parent->_M_remainder, |
6279 | ranges::end(__x._M_parent->_M_base) - *__x._M_parent->_M_current); |
6280 | } |
6281 | |
6282 | friend constexpr difference_type |
6283 | operator-(const _InnerIter& __x, default_sentinel_t __y) |
6284 | requires sized_sentinel_for<sentinel_t<_Vp>, iterator_t<_Vp>> |
6285 | { return -(__y - __x); } |
6286 | |
6287 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
6288 | // 3851. chunk_view::inner-iterator missing custom iter_move and iter_swap |
6289 | friend constexpr range_rvalue_reference_t<_Vp> |
6290 | iter_move(const _InnerIter& __i) |
6291 | noexcept(noexcept(ranges::iter_move(*__i._M_parent->_M_current))) |
6292 | { return ranges::iter_move(*__i._M_parent->_M_current); } |
6293 | |
6294 | friend constexpr void |
6295 | iter_swap(const _InnerIter& __x, const _InnerIter& __y) |
6296 | noexcept(noexcept(ranges::iter_swap(*__x._M_parent->_M_current, |
6297 | *__x._M_parent->_M_current))) |
6298 | requires indirectly_swappable<iterator_t<_Vp>> |
6299 | { return ranges::iter_swap(*__x._M_parent->_M_current, *__y._M_parent->_M_current); } |
6300 | }; |
6301 | |
6302 | template<view _Vp> |
6303 | requires forward_range<_Vp> |
6304 | class chunk_view<_Vp> : public view_interface<chunk_view<_Vp>> |
6305 | { |
6306 | _Vp _M_base; |
6307 | range_difference_t<_Vp> _M_n; |
6308 | template<bool> class _Iterator; |
6309 | |
6310 | public: |
6311 | constexpr explicit |
6312 | chunk_view(_Vp __base, range_difference_t<_Vp> __n) |
6313 | : _M_base(std::move(__base)), _M_n(__n) |
6314 | { __glibcxx_assert(__n > 0); } |
6315 | |
6316 | constexpr _Vp |
6317 | base() const & requires copy_constructible<_Vp> |
6318 | { return _M_base; } |
6319 | |
6320 | constexpr _Vp |
6321 | base() && |
6322 | { return std::move(_M_base); } |
6323 | |
6324 | constexpr auto |
6325 | begin() requires (!__detail::__simple_view<_Vp>) |
6326 | { return _Iterator<false>(this, ranges::begin(_M_base)); } |
6327 | |
6328 | constexpr auto |
6329 | begin() const requires forward_range<const _Vp> |
6330 | { return _Iterator<true>(this, ranges::begin(_M_base)); } |
6331 | |
6332 | constexpr auto |
6333 | end() requires (!__detail::__simple_view<_Vp>) |
6334 | { |
6335 | if constexpr (common_range<_Vp> && sized_range<_Vp>) |
6336 | { |
6337 | auto __missing = (_M_n - ranges::distance(_M_base) % _M_n) % _M_n; |
6338 | return _Iterator<false>(this, ranges::end(_M_base), __missing); |
6339 | } |
6340 | else if constexpr (common_range<_Vp> && !bidirectional_range<_Vp>) |
6341 | return _Iterator<false>(this, ranges::end(_M_base)); |
6342 | else |
6343 | return default_sentinel; |
6344 | } |
6345 | |
6346 | constexpr auto |
6347 | end() const requires forward_range<const _Vp> |
6348 | { |
6349 | if constexpr (common_range<const _Vp> && sized_range<const _Vp>) |
6350 | { |
6351 | auto __missing = (_M_n - ranges::distance(_M_base) % _M_n) % _M_n; |
6352 | return _Iterator<true>(this, ranges::end(_M_base), __missing); |
6353 | } |
6354 | else if constexpr (common_range<const _Vp> && !bidirectional_range<const _Vp>) |
6355 | return _Iterator<true>(this, ranges::end(_M_base)); |
6356 | else |
6357 | return default_sentinel; |
6358 | } |
6359 | |
6360 | constexpr auto |
6361 | size() requires sized_range<_Vp> |
6362 | { |
6363 | return __detail::__to_unsigned_like(__detail::__div_ceil |
6364 | (ranges::distance(_M_base), _M_n)); |
6365 | } |
6366 | |
6367 | constexpr auto |
6368 | size() const requires sized_range<const _Vp> |
6369 | { |
6370 | return __detail::__to_unsigned_like(__detail::__div_ceil |
6371 | (ranges::distance(_M_base), _M_n)); |
6372 | } |
6373 | }; |
6374 | |
6375 | template<typename _Vp> |
6376 | inline constexpr bool enable_borrowed_range<chunk_view<_Vp>> |
6377 | = forward_range<_Vp> && enable_borrowed_range<_Vp>; |
6378 | |
6379 | template<view _Vp> |
6380 | requires forward_range<_Vp> |
6381 | template<bool _Const> |
6382 | class chunk_view<_Vp>::_Iterator |
6383 | { |
6384 | using _Parent = __detail::__maybe_const_t<_Const, chunk_view>; |
6385 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
6386 | |
6387 | iterator_t<_Base> _M_current = iterator_t<_Base>(); |
6388 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
6389 | range_difference_t<_Base> _M_n = 0; |
6390 | range_difference_t<_Base> _M_missing = 0; |
6391 | |
6392 | constexpr |
6393 | _Iterator(_Parent* __parent, iterator_t<_Base> __current, |
6394 | range_difference_t<_Base> __missing = 0) |
6395 | : _M_current(__current), _M_end(ranges::end(__parent->_M_base)), |
6396 | _M_n(__parent->_M_n), _M_missing(__missing) |
6397 | { } |
6398 | |
6399 | static auto |
6400 | _S_iter_cat() |
6401 | { |
6402 | if constexpr (random_access_range<_Base>) |
6403 | return random_access_iterator_tag{}; |
6404 | else if constexpr (bidirectional_range<_Base>) |
6405 | return bidirectional_iterator_tag{}; |
6406 | else |
6407 | return forward_iterator_tag{}; |
6408 | } |
6409 | |
6410 | friend chunk_view; |
6411 | |
6412 | public: |
6413 | using iterator_category = input_iterator_tag; |
6414 | using iterator_concept = decltype(_S_iter_cat()); |
6415 | using value_type = decltype(views::take(subrange(_M_current, _M_end), _M_n)); |
6416 | using difference_type = range_difference_t<_Base>; |
6417 | |
6418 | _Iterator() = default; |
6419 | |
6420 | constexpr _Iterator(_Iterator<!_Const> __i) |
6421 | requires _Const |
6422 | && convertible_to<iterator_t<_Vp>, iterator_t<_Base>> |
6423 | && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
6424 | : _M_current(std::move(__i._M_current)), _M_end(std::move(__i._M_end)), |
6425 | _M_n(__i._M_n), _M_missing(__i._M_missing) |
6426 | { } |
6427 | |
6428 | constexpr iterator_t<_Base> |
6429 | base() const |
6430 | { return _M_current; } |
6431 | |
6432 | constexpr value_type |
6433 | operator*() const |
6434 | { |
6435 | __glibcxx_assert(_M_current != _M_end); |
6436 | return views::take(subrange(_M_current, _M_end), _M_n); |
6437 | } |
6438 | |
6439 | constexpr _Iterator& |
6440 | operator++() |
6441 | { |
6442 | __glibcxx_assert(_M_current != _M_end); |
6443 | _M_missing = ranges::advance(_M_current, _M_n, _M_end); |
6444 | return *this; |
6445 | } |
6446 | |
6447 | constexpr _Iterator |
6448 | operator++(int) |
6449 | { |
6450 | auto __tmp = *this; |
6451 | ++*this; |
6452 | return __tmp; |
6453 | } |
6454 | |
6455 | constexpr _Iterator& |
6456 | operator--() requires bidirectional_range<_Base> |
6457 | { |
6458 | ranges::advance(_M_current, _M_missing - _M_n); |
6459 | _M_missing = 0; |
6460 | return *this; |
6461 | } |
6462 | |
6463 | constexpr _Iterator |
6464 | operator--(int) requires bidirectional_range<_Base> |
6465 | { |
6466 | auto __tmp = *this; |
6467 | --*this; |
6468 | return __tmp; |
6469 | } |
6470 | |
6471 | constexpr _Iterator& |
6472 | operator+=(difference_type __x) |
6473 | requires random_access_range<_Base> |
6474 | { |
6475 | if (__x > 0) |
6476 | { |
6477 | __glibcxx_assert(ranges::distance(_M_current, _M_end) > _M_n * (__x - 1)); |
6478 | _M_missing = ranges::advance(_M_current, _M_n * __x, _M_end); |
6479 | } |
6480 | else if (__x < 0) |
6481 | { |
6482 | ranges::advance(_M_current, _M_n * __x + _M_missing); |
6483 | _M_missing = 0; |
6484 | } |
6485 | return *this; |
6486 | } |
6487 | |
6488 | constexpr _Iterator& |
6489 | operator-=(difference_type __x) |
6490 | requires random_access_range<_Base> |
6491 | { return *this += -__x; } |
6492 | |
6493 | constexpr value_type |
6494 | operator[](difference_type __n) const |
6495 | requires random_access_range<_Base> |
6496 | { return *(*this + __n); } |
6497 | |
6498 | friend constexpr bool |
6499 | operator==(const _Iterator& __x, const _Iterator& __y) |
6500 | { return __x._M_current == __y._M_current; } |
6501 | |
6502 | friend constexpr bool |
6503 | operator==(const _Iterator& __x, default_sentinel_t) |
6504 | { return __x._M_current == __x._M_end; } |
6505 | |
6506 | friend constexpr bool |
6507 | operator<(const _Iterator& __x, const _Iterator& __y) |
6508 | requires random_access_range<_Base> |
6509 | { return __x._M_current > __y._M_current; } |
6510 | |
6511 | friend constexpr bool |
6512 | operator>(const _Iterator& __x, const _Iterator& __y) |
6513 | requires random_access_range<_Base> |
6514 | { return __y < __x; } |
6515 | |
6516 | friend constexpr bool |
6517 | operator<=(const _Iterator& __x, const _Iterator& __y) |
6518 | requires random_access_range<_Base> |
6519 | { return !(__y < __x); } |
6520 | |
6521 | friend constexpr bool |
6522 | operator>=(const _Iterator& __x, const _Iterator& __y) |
6523 | requires random_access_range<_Base> |
6524 | { return !(__x < __y); } |
6525 | |
6526 | friend constexpr auto |
6527 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
6528 | requires random_access_range<_Base> |
6529 | && three_way_comparable<iterator_t<_Base>> |
6530 | { return __x._M_current <=> __y._M_current; } |
6531 | |
6532 | friend constexpr _Iterator |
6533 | operator+(const _Iterator& __i, difference_type __n) |
6534 | requires random_access_range<_Base> |
6535 | { |
6536 | auto __r = __i; |
6537 | __r += __n; |
6538 | return __r; |
6539 | } |
6540 | |
6541 | friend constexpr _Iterator |
6542 | operator+(difference_type __n, const _Iterator& __i) |
6543 | requires random_access_range<_Base> |
6544 | { |
6545 | auto __r = __i; |
6546 | __r += __n; |
6547 | return __r; |
6548 | } |
6549 | |
6550 | friend constexpr _Iterator |
6551 | operator-(const _Iterator& __i, difference_type __n) |
6552 | requires random_access_range<_Base> |
6553 | { |
6554 | auto __r = __i; |
6555 | __r -= __n; |
6556 | return __r; |
6557 | } |
6558 | |
6559 | friend constexpr difference_type |
6560 | operator-(const _Iterator& __x, const _Iterator& __y) |
6561 | requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>> |
6562 | { |
6563 | return (__x._M_current - __y._M_current |
6564 | + __x._M_missing - __y._M_missing) / __x._M_n; |
6565 | } |
6566 | |
6567 | friend constexpr difference_type |
6568 | operator-(default_sentinel_t __y, const _Iterator& __x) |
6569 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base>> |
6570 | { return __detail::__div_ceil(__x._M_end - __x._M_current, __x._M_n); } |
6571 | |
6572 | friend constexpr difference_type |
6573 | operator-(const _Iterator& __x, default_sentinel_t __y) |
6574 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base>> |
6575 | { return -(__y - __x); } |
6576 | }; |
6577 | |
6578 | namespace views |
6579 | { |
6580 | namespace __detail |
6581 | { |
6582 | template<typename _Range, typename _Dp> |
6583 | concept __can_chunk_view |
6584 | = requires { chunk_view(std::declval<_Range>(), std::declval<_Dp>()); }; |
6585 | } |
6586 | |
6587 | struct _Chunk : __adaptor::_RangeAdaptor<_Chunk> |
6588 | { |
6589 | template<viewable_range _Range, typename _Dp = range_difference_t<_Range>> |
6590 | requires __detail::__can_chunk_view<_Range, _Dp> |
6591 | constexpr auto |
6592 | operator() [[nodiscard]] (_Range&& __r, type_identity_t<_Dp> __n) const |
6593 | { return chunk_view(std::forward<_Range>(__r), __n); } |
6594 | |
6595 | using __adaptor::_RangeAdaptor<_Chunk>::operator(); |
6596 | static constexpr int _S_arity = 2; |
6597 | static constexpr bool = true; |
6598 | }; |
6599 | |
6600 | inline constexpr _Chunk chunk; |
6601 | } |
6602 | #endif // __cpp_lib_ranges_chunk |
6603 | |
6604 | #ifdef __cpp_lib_ranges_slide // C++ >= 23 |
6605 | namespace __detail |
6606 | { |
6607 | template<typename _Vp> |
6608 | concept __slide_caches_nothing = random_access_range<_Vp> && sized_range<_Vp>; |
6609 | |
6610 | template<typename _Vp> |
6611 | concept __slide_caches_last |
6612 | = !__slide_caches_nothing<_Vp> && bidirectional_range<_Vp> && common_range<_Vp>; |
6613 | |
6614 | template<typename _Vp> |
6615 | concept __slide_caches_first |
6616 | = !__slide_caches_nothing<_Vp> && !__slide_caches_last<_Vp>; |
6617 | } |
6618 | |
6619 | template<forward_range _Vp> |
6620 | requires view<_Vp> |
6621 | class slide_view : public view_interface<slide_view<_Vp>> |
6622 | { |
6623 | _Vp _M_base; |
6624 | range_difference_t<_Vp> _M_n; |
6625 | [[no_unique_address]] |
6626 | __detail::__maybe_present_t<__detail::__slide_caches_first<_Vp>, |
6627 | __detail::_CachedPosition<_Vp>, 0> _M_cached_begin; |
6628 | [[no_unique_address]] |
6629 | __detail::__maybe_present_t<__detail::__slide_caches_last<_Vp>, |
6630 | __detail::_CachedPosition<_Vp>, 1> _M_cached_end; |
6631 | |
6632 | template<bool> class _Iterator; |
6633 | class _Sentinel; |
6634 | |
6635 | public: |
6636 | constexpr explicit |
6637 | slide_view(_Vp __base, range_difference_t<_Vp> __n) |
6638 | : _M_base(std::move(__base)), _M_n(__n) |
6639 | { __glibcxx_assert(__n > 0); } |
6640 | |
6641 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
6642 | // 3848. adjacent_view, adjacent_transform_view and slide_view missing base accessor |
6643 | constexpr _Vp |
6644 | base() const & requires copy_constructible<_Vp> |
6645 | { return _M_base; } |
6646 | |
6647 | constexpr _Vp |
6648 | base() && |
6649 | { return std::move(_M_base); } |
6650 | |
6651 | constexpr auto |
6652 | begin() requires (!(__detail::__simple_view<_Vp> |
6653 | && __detail::__slide_caches_nothing<const _Vp>)) |
6654 | { |
6655 | if constexpr (__detail::__slide_caches_first<_Vp>) |
6656 | { |
6657 | iterator_t<_Vp> __it; |
6658 | if (_M_cached_begin._M_has_value()) |
6659 | __it = _M_cached_begin._M_get(_M_base); |
6660 | else |
6661 | { |
6662 | __it = ranges::next(ranges::begin(_M_base), _M_n - 1, ranges::end(_M_base)); |
6663 | _M_cached_begin._M_set(_M_base, __it); |
6664 | } |
6665 | return _Iterator<false>(ranges::begin(_M_base), std::move(__it), _M_n); |
6666 | } |
6667 | else |
6668 | return _Iterator<false>(ranges::begin(_M_base), _M_n); |
6669 | } |
6670 | |
6671 | constexpr auto |
6672 | begin() const requires __detail::__slide_caches_nothing<const _Vp> |
6673 | { return _Iterator<true>(ranges::begin(_M_base), _M_n); } |
6674 | |
6675 | constexpr auto |
6676 | end() requires (!(__detail::__simple_view<_Vp> |
6677 | && __detail::__slide_caches_nothing<const _Vp>)) |
6678 | { |
6679 | if constexpr (__detail::__slide_caches_nothing<_Vp>) |
6680 | return _Iterator<false>(ranges::begin(_M_base) + range_difference_t<_Vp>(size()), |
6681 | _M_n); |
6682 | else if constexpr (__detail::__slide_caches_last<_Vp>) |
6683 | { |
6684 | iterator_t<_Vp> __it; |
6685 | if (_M_cached_end._M_has_value()) |
6686 | __it = _M_cached_end._M_get(_M_base); |
6687 | else |
6688 | { |
6689 | __it = ranges::prev(ranges::end(_M_base), _M_n - 1, ranges::begin(_M_base)); |
6690 | _M_cached_end._M_set(_M_base, __it); |
6691 | } |
6692 | return _Iterator<false>(std::move(__it), _M_n); |
6693 | } |
6694 | else if constexpr (common_range<_Vp>) |
6695 | return _Iterator<false>(ranges::end(_M_base), ranges::end(_M_base), _M_n); |
6696 | else |
6697 | return _Sentinel(ranges::end(_M_base)); |
6698 | } |
6699 | |
6700 | constexpr auto |
6701 | end() const requires __detail::__slide_caches_nothing<const _Vp> |
6702 | { return begin() + range_difference_t<const _Vp>(size()); } |
6703 | |
6704 | constexpr auto |
6705 | size() requires sized_range<_Vp> |
6706 | { |
6707 | auto __sz = ranges::distance(_M_base) - _M_n + 1; |
6708 | if (__sz < 0) |
6709 | __sz = 0; |
6710 | return __detail::__to_unsigned_like(__sz); |
6711 | } |
6712 | |
6713 | constexpr auto |
6714 | size() const requires sized_range<const _Vp> |
6715 | { |
6716 | auto __sz = ranges::distance(_M_base) - _M_n + 1; |
6717 | if (__sz < 0) |
6718 | __sz = 0; |
6719 | return __detail::__to_unsigned_like(__sz); |
6720 | } |
6721 | }; |
6722 | |
6723 | template<typename _Range> |
6724 | slide_view(_Range&&, range_difference_t<_Range>) -> slide_view<views::all_t<_Range>>; |
6725 | |
6726 | template<typename _Vp> |
6727 | inline constexpr bool enable_borrowed_range<slide_view<_Vp>> |
6728 | = enable_borrowed_range<_Vp>; |
6729 | |
6730 | template<forward_range _Vp> |
6731 | requires view<_Vp> |
6732 | template<bool _Const> |
6733 | class slide_view<_Vp>::_Iterator |
6734 | { |
6735 | using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
6736 | static constexpr bool _S_last_elt_present |
6737 | = __detail::__slide_caches_first<_Base>; |
6738 | |
6739 | iterator_t<_Base> _M_current = iterator_t<_Base>(); |
6740 | [[no_unique_address]] |
6741 | __detail::__maybe_present_t<_S_last_elt_present, iterator_t<_Base>> |
6742 | _M_last_elt = decltype(_M_last_elt)(); |
6743 | range_difference_t<_Base> _M_n = 0; |
6744 | |
6745 | constexpr |
6746 | _Iterator(iterator_t<_Base> __current, range_difference_t<_Base> __n) |
6747 | requires (!_S_last_elt_present) |
6748 | : _M_current(__current), _M_n(__n) |
6749 | { } |
6750 | |
6751 | constexpr |
6752 | _Iterator(iterator_t<_Base> __current, iterator_t<_Base> __last_elt, |
6753 | range_difference_t<_Base> __n) |
6754 | requires _S_last_elt_present |
6755 | : _M_current(__current), _M_last_elt(__last_elt), _M_n(__n) |
6756 | { } |
6757 | |
6758 | static auto |
6759 | _S_iter_concept() |
6760 | { |
6761 | if constexpr (random_access_range<_Base>) |
6762 | return random_access_iterator_tag{}; |
6763 | else if constexpr (bidirectional_range<_Base>) |
6764 | return bidirectional_iterator_tag{}; |
6765 | else |
6766 | return forward_iterator_tag{}; |
6767 | } |
6768 | |
6769 | friend slide_view; |
6770 | friend slide_view::_Sentinel; |
6771 | |
6772 | public: |
6773 | using iterator_category = input_iterator_tag; |
6774 | using iterator_concept = decltype(_S_iter_concept()); |
6775 | using value_type = decltype(views::counted(_M_current, _M_n)); |
6776 | using difference_type = range_difference_t<_Base>; |
6777 | |
6778 | _Iterator() = default; |
6779 | |
6780 | constexpr |
6781 | _Iterator(_Iterator<!_Const> __i) |
6782 | requires _Const && convertible_to<iterator_t<_Vp>, iterator_t<_Base>> |
6783 | : _M_current(std::move(__i._M_current)), _M_n(__i._M_n) |
6784 | { } |
6785 | |
6786 | constexpr auto |
6787 | operator*() const |
6788 | { return views::counted(_M_current, _M_n); } |
6789 | |
6790 | constexpr _Iterator& |
6791 | operator++() |
6792 | { |
6793 | ++_M_current; |
6794 | if constexpr (_S_last_elt_present) |
6795 | ++_M_last_elt; |
6796 | return *this; |
6797 | } |
6798 | |
6799 | constexpr _Iterator |
6800 | operator++(int) |
6801 | { |
6802 | auto __tmp = *this; |
6803 | ++*this; |
6804 | return __tmp; |
6805 | } |
6806 | |
6807 | constexpr _Iterator& |
6808 | operator--() requires bidirectional_range<_Base> |
6809 | { |
6810 | --_M_current; |
6811 | if constexpr (_S_last_elt_present) |
6812 | --_M_last_elt; |
6813 | return *this; |
6814 | } |
6815 | |
6816 | constexpr _Iterator |
6817 | operator--(int) requires bidirectional_range<_Base> |
6818 | { |
6819 | auto __tmp = *this; |
6820 | --*this; |
6821 | return __tmp; |
6822 | } |
6823 | |
6824 | constexpr _Iterator& |
6825 | operator+=(difference_type __x) |
6826 | requires random_access_range<_Base> |
6827 | { |
6828 | _M_current += __x; |
6829 | if constexpr (_S_last_elt_present) |
6830 | _M_last_elt += __x; |
6831 | return *this; |
6832 | } |
6833 | |
6834 | constexpr _Iterator& |
6835 | operator-=(difference_type __x) |
6836 | requires random_access_range<_Base> |
6837 | { |
6838 | _M_current -= __x; |
6839 | if constexpr (_S_last_elt_present) |
6840 | _M_last_elt -= __x; |
6841 | return *this; |
6842 | } |
6843 | |
6844 | constexpr auto |
6845 | operator[](difference_type __n) const |
6846 | requires random_access_range<_Base> |
6847 | { return views::counted(_M_current + __n, _M_n); } |
6848 | |
6849 | friend constexpr bool |
6850 | operator==(const _Iterator& __x, const _Iterator& __y) |
6851 | { |
6852 | if constexpr (_S_last_elt_present) |
6853 | return __x._M_last_elt == __y._M_last_elt; |
6854 | else |
6855 | return __x._M_current == __y._M_current; |
6856 | } |
6857 | |
6858 | friend constexpr bool |
6859 | operator<(const _Iterator& __x, const _Iterator& __y) |
6860 | requires random_access_range<_Base> |
6861 | { return __x._M_current < __y._M_current; } |
6862 | |
6863 | friend constexpr bool |
6864 | operator>(const _Iterator& __x, const _Iterator& __y) |
6865 | requires random_access_range<_Base> |
6866 | { return __y < __x; } |
6867 | |
6868 | friend constexpr bool |
6869 | operator<=(const _Iterator& __x, const _Iterator& __y) |
6870 | requires random_access_range<_Base> |
6871 | { return !(__y < __x); } |
6872 | |
6873 | friend constexpr bool |
6874 | operator>=(const _Iterator& __x, const _Iterator& __y) |
6875 | requires random_access_range<_Base> |
6876 | { return !(__x < __y); } |
6877 | |
6878 | friend constexpr auto |
6879 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
6880 | requires random_access_range<_Base> |
6881 | && three_way_comparable<iterator_t<_Base>> |
6882 | { return __x._M_current <=> __y._M_current; } |
6883 | |
6884 | friend constexpr _Iterator |
6885 | operator+(const _Iterator& __i, difference_type __n) |
6886 | requires random_access_range<_Base> |
6887 | { |
6888 | auto __r = __i; |
6889 | __r += __n; |
6890 | return __r; |
6891 | } |
6892 | |
6893 | friend constexpr _Iterator |
6894 | operator+(difference_type __n, const _Iterator& __i) |
6895 | requires random_access_range<_Base> |
6896 | { |
6897 | auto __r = __i; |
6898 | __r += __n; |
6899 | return __r; |
6900 | } |
6901 | |
6902 | friend constexpr _Iterator |
6903 | operator-(const _Iterator& __i, difference_type __n) |
6904 | requires random_access_range<_Base> |
6905 | { |
6906 | auto __r = __i; |
6907 | __r -= __n; |
6908 | return __r; |
6909 | } |
6910 | |
6911 | friend constexpr difference_type |
6912 | operator-(const _Iterator& __x, const _Iterator& __y) |
6913 | requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>> |
6914 | { |
6915 | if constexpr (_S_last_elt_present) |
6916 | return __x._M_last_elt - __y._M_last_elt; |
6917 | else |
6918 | return __x._M_current - __y._M_current; |
6919 | } |
6920 | }; |
6921 | |
6922 | template<forward_range _Vp> |
6923 | requires view<_Vp> |
6924 | class slide_view<_Vp>::_Sentinel |
6925 | { |
6926 | sentinel_t<_Vp> _M_end = sentinel_t<_Vp>(); |
6927 | |
6928 | constexpr explicit |
6929 | _Sentinel(sentinel_t<_Vp> __end) |
6930 | : _M_end(__end) |
6931 | { } |
6932 | |
6933 | friend slide_view; |
6934 | |
6935 | public: |
6936 | _Sentinel() = default; |
6937 | |
6938 | friend constexpr bool |
6939 | operator==(const _Iterator<false>& __x, const _Sentinel& __y) |
6940 | { return __x._M_last_elt == __y._M_end; } |
6941 | |
6942 | friend constexpr range_difference_t<_Vp> |
6943 | operator-(const _Iterator<false>& __x, const _Sentinel& __y) |
6944 | requires sized_sentinel_for<sentinel_t<_Vp>, iterator_t<_Vp>> |
6945 | { return __x._M_last_elt - __y._M_end; } |
6946 | |
6947 | friend constexpr range_difference_t<_Vp> |
6948 | operator-(const _Sentinel& __y, const _Iterator<false>& __x) |
6949 | requires sized_sentinel_for<sentinel_t<_Vp>, iterator_t<_Vp>> |
6950 | { return __y._M_end -__x._M_last_elt; } |
6951 | }; |
6952 | |
6953 | namespace views |
6954 | { |
6955 | namespace __detail |
6956 | { |
6957 | template<typename _Range, typename _Dp> |
6958 | concept __can_slide_view |
6959 | = requires { slide_view(std::declval<_Range>(), std::declval<_Dp>()); }; |
6960 | } |
6961 | |
6962 | struct _Slide : __adaptor::_RangeAdaptor<_Slide> |
6963 | { |
6964 | template<viewable_range _Range, typename _Dp = range_difference_t<_Range>> |
6965 | requires __detail::__can_slide_view<_Range, _Dp> |
6966 | constexpr auto |
6967 | operator() [[nodiscard]] (_Range&& __r, type_identity_t<_Dp> __n) const |
6968 | { return slide_view(std::forward<_Range>(__r), __n); } |
6969 | |
6970 | using __adaptor::_RangeAdaptor<_Slide>::operator(); |
6971 | static constexpr int _S_arity = 2; |
6972 | static constexpr bool = true; |
6973 | }; |
6974 | |
6975 | inline constexpr _Slide slide; |
6976 | } |
6977 | #endif // __cpp_lib_ranges_slide |
6978 | |
6979 | #ifdef __cpp_lib_ranges_chunk_by // C++ >= 23 |
6980 | template<forward_range _Vp, |
6981 | indirect_binary_predicate<iterator_t<_Vp>, iterator_t<_Vp>> _Pred> |
6982 | requires view<_Vp> && is_object_v<_Pred> |
6983 | class chunk_by_view : public view_interface<chunk_by_view<_Vp, _Pred>> |
6984 | { |
6985 | _Vp _M_base = _Vp(); |
6986 | __detail::__box<_Pred> _M_pred; |
6987 | __detail::_CachedPosition<_Vp> _M_cached_begin; |
6988 | |
6989 | constexpr iterator_t<_Vp> |
6990 | _M_find_next(iterator_t<_Vp> __current) |
6991 | { |
6992 | __glibcxx_assert(_M_pred.has_value()); |
6993 | auto __pred = [this]<typename _Tp, typename _Up>(_Tp&& __x, _Up&& __y) { |
6994 | return !bool((*_M_pred)(std::forward<_Tp>(__x), std::forward<_Up>(__y))); |
6995 | }; |
6996 | auto __it = ranges::adjacent_find(__current, ranges::end(_M_base), __pred); |
6997 | return ranges::next(__it, 1, ranges::end(_M_base)); |
6998 | } |
6999 | |
7000 | constexpr iterator_t<_Vp> |
7001 | _M_find_prev(iterator_t<_Vp> __current) requires bidirectional_range<_Vp> |
7002 | { |
7003 | __glibcxx_assert(_M_pred.has_value()); |
7004 | auto __pred = [this]<typename _Tp, typename _Up>(_Tp&& __x, _Up&& __y) { |
7005 | return !bool((*_M_pred)(std::forward<_Up>(__y), std::forward<_Tp>(__x))); |
7006 | }; |
7007 | auto __rbegin = std::make_reverse_iterator(__current); |
7008 | auto __rend = std::make_reverse_iterator(ranges::begin(_M_base)); |
7009 | __glibcxx_assert(__rbegin != __rend); |
7010 | auto __it = ranges::adjacent_find(__rbegin, __rend, __pred).base(); |
7011 | return ranges::prev(__it, 1, ranges::begin(_M_base)); |
7012 | } |
7013 | |
7014 | class _Iterator; |
7015 | |
7016 | public: |
7017 | chunk_by_view() requires (default_initializable<_Vp> |
7018 | && default_initializable<_Pred>) |
7019 | = default; |
7020 | |
7021 | constexpr explicit |
7022 | chunk_by_view(_Vp __base, _Pred __pred) |
7023 | : _M_base(std::move(__base)), _M_pred(std::move(__pred)) |
7024 | { } |
7025 | |
7026 | constexpr _Vp |
7027 | base() const & requires copy_constructible<_Vp> |
7028 | { return _M_base; } |
7029 | |
7030 | constexpr _Vp |
7031 | base() && |
7032 | { return std::move(_M_base); } |
7033 | |
7034 | constexpr const _Pred& |
7035 | pred() const |
7036 | { return *_M_pred; } |
7037 | |
7038 | constexpr _Iterator |
7039 | begin() |
7040 | { |
7041 | __glibcxx_assert(_M_pred.has_value()); |
7042 | iterator_t<_Vp> __it; |
7043 | if (_M_cached_begin._M_has_value()) |
7044 | __it = _M_cached_begin._M_get(_M_base); |
7045 | else |
7046 | { |
7047 | __it = _M_find_next(current: ranges::begin(_M_base)); |
7048 | _M_cached_begin._M_set(_M_base, __it); |
7049 | } |
7050 | return _Iterator(*this, ranges::begin(_M_base), __it); |
7051 | } |
7052 | |
7053 | constexpr auto |
7054 | end() |
7055 | { |
7056 | if constexpr (common_range<_Vp>) |
7057 | return _Iterator(*this, ranges::end(_M_base), ranges::end(_M_base)); |
7058 | else |
7059 | return default_sentinel; |
7060 | } |
7061 | }; |
7062 | |
7063 | template<typename _Range, typename _Pred> |
7064 | chunk_by_view(_Range&&, _Pred) -> chunk_by_view<views::all_t<_Range>, _Pred>; |
7065 | |
7066 | template<forward_range _Vp, |
7067 | indirect_binary_predicate<iterator_t<_Vp>, iterator_t<_Vp>> _Pred> |
7068 | requires view<_Vp> && is_object_v<_Pred> |
7069 | class chunk_by_view<_Vp, _Pred>::_Iterator |
7070 | { |
7071 | chunk_by_view* _M_parent = nullptr; |
7072 | iterator_t<_Vp> _M_current = iterator_t<_Vp>(); |
7073 | iterator_t<_Vp> _M_next = iterator_t<_Vp>(); |
7074 | |
7075 | constexpr |
7076 | _Iterator(chunk_by_view& __parent, iterator_t<_Vp> __current, iterator_t<_Vp> __next) |
7077 | : _M_parent(std::__addressof(__parent)), _M_current(__current), _M_next(__next) |
7078 | { } |
7079 | |
7080 | static auto |
7081 | _S_iter_concept() |
7082 | { |
7083 | if constexpr (bidirectional_range<_Vp>) |
7084 | return bidirectional_iterator_tag{}; |
7085 | else |
7086 | return forward_iterator_tag{}; |
7087 | } |
7088 | |
7089 | friend chunk_by_view; |
7090 | |
7091 | public: |
7092 | using value_type = subrange<iterator_t<_Vp>>; |
7093 | using difference_type = range_difference_t<_Vp>; |
7094 | using iterator_category = input_iterator_tag; |
7095 | using iterator_concept = decltype(_S_iter_concept()); |
7096 | |
7097 | _Iterator() = default; |
7098 | |
7099 | constexpr value_type |
7100 | operator*() const |
7101 | { |
7102 | __glibcxx_assert(_M_current != _M_next); |
7103 | return ranges::subrange(_M_current, _M_next); |
7104 | } |
7105 | |
7106 | constexpr _Iterator& |
7107 | operator++() |
7108 | { |
7109 | __glibcxx_assert(_M_current != _M_next); |
7110 | _M_current = _M_next; |
7111 | _M_next = _M_parent->_M_find_next(current: _M_current); |
7112 | return *this; |
7113 | } |
7114 | |
7115 | constexpr _Iterator |
7116 | operator++(int) |
7117 | { |
7118 | auto __tmp = *this; |
7119 | ++*this; |
7120 | return __tmp; |
7121 | } |
7122 | |
7123 | constexpr _Iterator& |
7124 | operator--() requires bidirectional_range<_Vp> |
7125 | { |
7126 | _M_next = _M_current; |
7127 | _M_current = _M_parent->_M_find_prev(current: _M_next); |
7128 | return *this; |
7129 | } |
7130 | |
7131 | constexpr _Iterator |
7132 | operator--(int) requires bidirectional_range<_Vp> |
7133 | { |
7134 | auto __tmp = *this; |
7135 | --*this; |
7136 | return __tmp; |
7137 | } |
7138 | |
7139 | friend constexpr bool |
7140 | operator==(const _Iterator& __x, const _Iterator& __y) |
7141 | { return __x._M_current == __y._M_current; } |
7142 | |
7143 | friend constexpr bool |
7144 | operator==(const _Iterator& __x, default_sentinel_t) |
7145 | { return __x._M_current == __x._M_next; } |
7146 | }; |
7147 | |
7148 | namespace views |
7149 | { |
7150 | namespace __detail |
7151 | { |
7152 | template<typename _Range, typename _Pred> |
7153 | concept __can_chunk_by_view |
7154 | = requires { chunk_by_view(std::declval<_Range>(), std::declval<_Pred>()); }; |
7155 | } |
7156 | |
7157 | struct _ChunkBy : __adaptor::_RangeAdaptor<_ChunkBy> |
7158 | { |
7159 | template<viewable_range _Range, typename _Pred> |
7160 | requires __detail::__can_chunk_by_view<_Range, _Pred> |
7161 | constexpr auto |
7162 | operator() [[nodiscard]] (_Range&& __r, _Pred&& __pred) const |
7163 | { return chunk_by_view(std::forward<_Range>(__r), std::forward<_Pred>(__pred)); } |
7164 | |
7165 | using __adaptor::_RangeAdaptor<_ChunkBy>::operator(); |
7166 | static constexpr int _S_arity = 2; |
7167 | static constexpr bool = true; |
7168 | }; |
7169 | |
7170 | inline constexpr _ChunkBy chunk_by; |
7171 | } |
7172 | #endif // __cpp_lib_ranges_chunk_by |
7173 | |
7174 | #ifdef __cpp_lib_ranges_join_with // C++ >= 23 |
7175 | namespace __detail |
7176 | { |
7177 | template<typename _Range, typename _Pattern> |
7178 | concept __compatible_joinable_ranges |
7179 | = common_with<range_value_t<_Range>, range_value_t<_Pattern>> |
7180 | && common_reference_with<range_reference_t<_Range>, |
7181 | range_reference_t<_Pattern>> |
7182 | && common_reference_with<range_rvalue_reference_t<_Range>, |
7183 | range_rvalue_reference_t<_Pattern>>; |
7184 | |
7185 | template<typename _Range> |
7186 | concept __bidirectional_common = bidirectional_range<_Range> && common_range<_Range>; |
7187 | } |
7188 | |
7189 | template<input_range _Vp, forward_range _Pattern> |
7190 | requires view<_Vp> && view<_Pattern> |
7191 | && input_range<range_reference_t<_Vp>> |
7192 | && __detail::__compatible_joinable_ranges<range_reference_t<_Vp>, _Pattern> |
7193 | class join_with_view : public view_interface<join_with_view<_Vp, _Pattern>> |
7194 | { |
7195 | using _InnerRange = range_reference_t<_Vp>; |
7196 | |
7197 | _Vp _M_base = _Vp(); |
7198 | [[no_unique_address]] |
7199 | __detail::__maybe_present_t<!forward_range<_Vp>, |
7200 | __detail::__non_propagating_cache<iterator_t<_Vp>>> _M_outer_it; |
7201 | __detail::__non_propagating_cache<remove_cv_t<_InnerRange>> _M_inner; |
7202 | _Pattern _M_pattern = _Pattern(); |
7203 | |
7204 | template<bool _Const> using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
7205 | template<bool _Const> using _InnerBase = range_reference_t<_Base<_Const>>; |
7206 | template<bool _Const> using _PatternBase = __detail::__maybe_const_t<_Const, _Pattern>; |
7207 | |
7208 | template<bool _Const> using _OuterIter = iterator_t<_Base<_Const>>; |
7209 | template<bool _Const> using _InnerIter = iterator_t<_InnerBase<_Const>>; |
7210 | template<bool _Const> using _PatternIter = iterator_t<_PatternBase<_Const>>; |
7211 | |
7212 | template<bool _Const> |
7213 | static constexpr bool _S_ref_is_glvalue = is_reference_v<_InnerBase<_Const>>; |
7214 | |
7215 | template<bool _Const> |
7216 | struct __iter_cat |
7217 | { }; |
7218 | |
7219 | template<bool _Const> |
7220 | requires _S_ref_is_glvalue<_Const> |
7221 | && forward_range<_Base<_Const>> |
7222 | && forward_range<_InnerBase<_Const>> |
7223 | struct __iter_cat<_Const> |
7224 | { |
7225 | private: |
7226 | static auto |
7227 | _S_iter_cat() |
7228 | { |
7229 | using _OuterIter = join_with_view::_OuterIter<_Const>; |
7230 | using _InnerIter = join_with_view::_InnerIter<_Const>; |
7231 | using _PatternIter = join_with_view::_PatternIter<_Const>; |
7232 | using _OuterCat = typename iterator_traits<_OuterIter>::iterator_category; |
7233 | using _InnerCat = typename iterator_traits<_InnerIter>::iterator_category; |
7234 | using _PatternCat = typename iterator_traits<_PatternIter>::iterator_category; |
7235 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
7236 | // 3798. Rvalue reference and iterator_category |
7237 | if constexpr (!is_reference_v<common_reference_t<iter_reference_t<_InnerIter>, |
7238 | iter_reference_t<_PatternIter>>>) |
7239 | return input_iterator_tag{}; |
7240 | else if constexpr (derived_from<_OuterCat, bidirectional_iterator_tag> |
7241 | && derived_from<_InnerCat, bidirectional_iterator_tag> |
7242 | && derived_from<_PatternCat, bidirectional_iterator_tag> |
7243 | && common_range<_InnerBase<_Const>> |
7244 | && common_range<_PatternBase<_Const>>) |
7245 | return bidirectional_iterator_tag{}; |
7246 | else if constexpr (derived_from<_OuterCat, forward_iterator_tag> |
7247 | && derived_from<_InnerCat, forward_iterator_tag> |
7248 | && derived_from<_PatternCat, forward_iterator_tag>) |
7249 | return forward_iterator_tag{}; |
7250 | else |
7251 | return input_iterator_tag{}; |
7252 | } |
7253 | public: |
7254 | using iterator_category = decltype(_S_iter_cat()); |
7255 | }; |
7256 | |
7257 | template<bool> struct _Iterator; |
7258 | template<bool> struct _Sentinel; |
7259 | |
7260 | public: |
7261 | join_with_view() requires (default_initializable<_Vp> |
7262 | && default_initializable<_Pattern>) |
7263 | = default; |
7264 | |
7265 | constexpr |
7266 | join_with_view(_Vp __base, _Pattern __pattern) |
7267 | : _M_base(std::move(__base)), _M_pattern(std::move(__pattern)) |
7268 | { } |
7269 | |
7270 | template<input_range _Range> |
7271 | requires constructible_from<_Vp, views::all_t<_Range>> |
7272 | && constructible_from<_Pattern, single_view<range_value_t<_InnerRange>>> |
7273 | constexpr |
7274 | join_with_view(_Range&& __r, range_value_t<_InnerRange> __e) |
7275 | : _M_base(views::all(std::forward<_Range>(__r))), |
7276 | _M_pattern(views::single(std::move(__e))) |
7277 | { } |
7278 | |
7279 | constexpr _Vp |
7280 | base() const& requires copy_constructible<_Vp> |
7281 | { return _M_base; } |
7282 | |
7283 | constexpr _Vp |
7284 | base() && |
7285 | { return std::move(_M_base); } |
7286 | |
7287 | constexpr auto |
7288 | begin() |
7289 | { |
7290 | if constexpr (forward_range<_Vp>) |
7291 | { |
7292 | constexpr bool __use_const = is_reference_v<_InnerRange> |
7293 | && __detail::__simple_view<_Vp> && __detail::__simple_view<_Pattern>; |
7294 | return _Iterator<__use_const>{*this, ranges::begin(_M_base)}; |
7295 | } |
7296 | else |
7297 | { |
7298 | _M_outer_it = ranges::begin(_M_base); |
7299 | return _Iterator<false>{*this}; |
7300 | } |
7301 | } |
7302 | |
7303 | constexpr auto |
7304 | begin() const |
7305 | requires forward_range<const _Vp> |
7306 | && forward_range<const _Pattern> |
7307 | && is_reference_v<range_reference_t<const _Vp>> |
7308 | && input_range<range_reference_t<const _Vp>> |
7309 | { return _Iterator<true>{*this, ranges::begin(_M_base)}; } |
7310 | |
7311 | constexpr auto |
7312 | end() |
7313 | { |
7314 | constexpr bool __use_const |
7315 | = __detail::__simple_view<_Vp> && __detail::__simple_view<_Pattern>; |
7316 | if constexpr (is_reference_v<_InnerRange> |
7317 | && forward_range<_Vp> && common_range<_Vp> |
7318 | && forward_range<_InnerRange> && common_range<_InnerRange>) |
7319 | return _Iterator<__use_const>{*this, ranges::end(_M_base)}; |
7320 | else |
7321 | return _Sentinel<__use_const>{*this}; |
7322 | } |
7323 | |
7324 | constexpr auto |
7325 | end() const |
7326 | requires forward_range<const _Vp> |
7327 | && forward_range<const _Pattern> |
7328 | && is_reference_v<range_reference_t<const _Vp>> |
7329 | && input_range<range_reference_t<const _Vp>> |
7330 | { |
7331 | using _InnerConstRange = range_reference_t<const _Vp>; |
7332 | if constexpr (forward_range<_InnerConstRange> |
7333 | && common_range<const _Vp> |
7334 | && common_range<_InnerConstRange>) |
7335 | return _Iterator<true>{*this, ranges::end(_M_base)}; |
7336 | else |
7337 | return _Sentinel<true>{*this}; |
7338 | } |
7339 | }; |
7340 | |
7341 | template<typename _Range, typename _Pattern> |
7342 | join_with_view(_Range&&, _Pattern&&) |
7343 | -> join_with_view<views::all_t<_Range>, views::all_t<_Pattern>>; |
7344 | |
7345 | template<input_range _Range> |
7346 | join_with_view(_Range&&, range_value_t<range_reference_t<_Range>>) |
7347 | -> join_with_view<views::all_t<_Range>, |
7348 | single_view<range_value_t<range_reference_t<_Range>>>>; |
7349 | |
7350 | template<input_range _Vp, forward_range _Pattern> |
7351 | requires view<_Vp> && view<_Pattern> |
7352 | && input_range<range_reference_t<_Vp>> |
7353 | && __detail::__compatible_joinable_ranges<range_reference_t<_Vp>, _Pattern> |
7354 | template<bool _Const> |
7355 | class join_with_view<_Vp, _Pattern>::_Iterator : public __iter_cat<_Const> |
7356 | { |
7357 | using _Parent = __detail::__maybe_const_t<_Const, join_with_view>; |
7358 | using _Base = join_with_view::_Base<_Const>; |
7359 | using _InnerBase = join_with_view::_InnerBase<_Const>; |
7360 | using _PatternBase = join_with_view::_PatternBase<_Const>; |
7361 | |
7362 | using _OuterIter = join_with_view::_OuterIter<_Const>; |
7363 | using _InnerIter = join_with_view::_InnerIter<_Const>; |
7364 | using _PatternIter = join_with_view::_PatternIter<_Const>; |
7365 | |
7366 | static constexpr bool _S_ref_is_glvalue = join_with_view::_S_ref_is_glvalue<_Const>; |
7367 | |
7368 | _Parent* _M_parent = nullptr; |
7369 | [[no_unique_address]] |
7370 | __detail::__maybe_present_t<forward_range<_Base>, _OuterIter> _M_outer_it; |
7371 | variant<_PatternIter, _InnerIter> _M_inner_it; |
7372 | |
7373 | constexpr _OuterIter& |
7374 | _M_get_outer() |
7375 | { |
7376 | if constexpr (forward_range<_Base>) |
7377 | return _M_outer_it; |
7378 | else |
7379 | return *_M_parent->_M_outer_it; |
7380 | } |
7381 | |
7382 | constexpr const _OuterIter& |
7383 | _M_get_outer() const |
7384 | { |
7385 | if constexpr (forward_range<_Base>) |
7386 | return _M_outer_it; |
7387 | else |
7388 | return *_M_parent->_M_outer_it; |
7389 | } |
7390 | |
7391 | constexpr |
7392 | _Iterator(_Parent& __parent, _OuterIter __outer) |
7393 | requires forward_range<_Base> |
7394 | : _M_parent(std::__addressof(__parent)), _M_outer_it(std::move(__outer)) |
7395 | { |
7396 | if (_M_get_outer() != ranges::end(_M_parent->_M_base)) |
7397 | { |
7398 | auto&& __inner = _M_update_inner(); |
7399 | _M_inner_it.template emplace<1>(ranges::begin(__inner)); |
7400 | _M_satisfy(); |
7401 | } |
7402 | } |
7403 | |
7404 | constexpr |
7405 | _Iterator(_Parent& __parent) |
7406 | requires (!forward_range<_Base>) |
7407 | : _M_parent(std::__addressof(__parent)) |
7408 | { |
7409 | if (_M_get_outer() != ranges::end(_M_parent->_M_base)) |
7410 | { |
7411 | auto&& __inner = _M_update_inner(); |
7412 | _M_inner_it.template emplace<1>(ranges::begin(__inner)); |
7413 | _M_satisfy(); |
7414 | } |
7415 | } |
7416 | |
7417 | constexpr auto& |
7418 | _M_update_inner() |
7419 | { |
7420 | _OuterIter& __outer = _M_get_outer(); |
7421 | if constexpr (_S_ref_is_glvalue) |
7422 | return __detail::__as_lvalue(*__outer); |
7423 | else |
7424 | return _M_parent->_M_inner._M_emplace_deref(__outer); |
7425 | } |
7426 | |
7427 | constexpr auto& |
7428 | _M_get_inner() |
7429 | { |
7430 | if constexpr (_S_ref_is_glvalue) |
7431 | return __detail::__as_lvalue(*_M_get_outer()); |
7432 | else |
7433 | return *_M_parent->_M_inner; |
7434 | } |
7435 | |
7436 | constexpr void |
7437 | _M_satisfy() |
7438 | { |
7439 | while (true) |
7440 | { |
7441 | if (_M_inner_it.index() == 0) |
7442 | { |
7443 | if (std::get<0>(_M_inner_it) != ranges::end(_M_parent->_M_pattern)) |
7444 | break; |
7445 | |
7446 | auto&& __inner = _M_update_inner(); |
7447 | _M_inner_it.template emplace<1>(ranges::begin(__inner)); |
7448 | } |
7449 | else |
7450 | { |
7451 | auto&& __inner = _M_get_inner(); |
7452 | if (std::get<1>(_M_inner_it) != ranges::end(__inner)) |
7453 | break; |
7454 | |
7455 | if (++_M_get_outer() == ranges::end(_M_parent->_M_base)) |
7456 | { |
7457 | if constexpr (_S_ref_is_glvalue) |
7458 | _M_inner_it.template emplace<0>(); |
7459 | break; |
7460 | } |
7461 | |
7462 | _M_inner_it.template emplace<0>(ranges::begin(_M_parent->_M_pattern)); |
7463 | } |
7464 | } |
7465 | } |
7466 | |
7467 | static auto |
7468 | _S_iter_concept() |
7469 | { |
7470 | if constexpr (_S_ref_is_glvalue |
7471 | && bidirectional_range<_Base> |
7472 | && __detail::__bidirectional_common<_InnerBase> |
7473 | && __detail::__bidirectional_common<_PatternBase>) |
7474 | return bidirectional_iterator_tag{}; |
7475 | else if constexpr (_S_ref_is_glvalue |
7476 | && forward_range<_Base> |
7477 | && forward_range<_InnerBase>) |
7478 | return forward_iterator_tag{}; |
7479 | else |
7480 | return input_iterator_tag{}; |
7481 | } |
7482 | |
7483 | friend join_with_view; |
7484 | |
7485 | public: |
7486 | using iterator_concept = decltype(_S_iter_concept()); |
7487 | // iterator_category defined in join_with_view::__iter_cat |
7488 | using value_type = common_type_t<iter_value_t<_InnerIter>, |
7489 | iter_value_t<_PatternIter>>; |
7490 | using difference_type = common_type_t<iter_difference_t<_OuterIter>, |
7491 | iter_difference_t<_InnerIter>, |
7492 | iter_difference_t<_PatternIter>>; |
7493 | |
7494 | _Iterator() = default; |
7495 | |
7496 | constexpr |
7497 | _Iterator(_Iterator<!_Const> __i) |
7498 | requires _Const |
7499 | && convertible_to<iterator_t<_Vp>, _OuterIter> |
7500 | && convertible_to<iterator_t<_InnerRange>, _InnerIter> |
7501 | && convertible_to<iterator_t<_Pattern>, _PatternIter> |
7502 | : _M_parent(__i._M_parent), |
7503 | _M_outer_it(std::move(__i._M_outer_it)) |
7504 | { |
7505 | if (__i._M_inner_it.index() == 0) |
7506 | _M_inner_it.template emplace<0>(std::get<0>(std::move(__i._M_inner_it))); |
7507 | else |
7508 | _M_inner_it.template emplace<1>(std::get<1>(std::move(__i._M_inner_it))); |
7509 | } |
7510 | |
7511 | constexpr common_reference_t<iter_reference_t<_InnerIter>, |
7512 | iter_reference_t<_PatternIter>> |
7513 | operator*() const |
7514 | { |
7515 | if (_M_inner_it.index() == 0) |
7516 | return *std::get<0>(_M_inner_it); |
7517 | else |
7518 | return *std::get<1>(_M_inner_it); |
7519 | } |
7520 | |
7521 | constexpr _Iterator& |
7522 | operator++() |
7523 | { |
7524 | if (_M_inner_it.index() == 0) |
7525 | ++std::get<0>(_M_inner_it); |
7526 | else |
7527 | ++std::get<1>(_M_inner_it); |
7528 | _M_satisfy(); |
7529 | return *this; |
7530 | } |
7531 | |
7532 | constexpr void |
7533 | operator++(int) |
7534 | { ++*this; } |
7535 | |
7536 | constexpr _Iterator |
7537 | operator++(int) |
7538 | requires _S_ref_is_glvalue |
7539 | && forward_iterator<_OuterIter> && forward_iterator<_InnerIter> |
7540 | { |
7541 | _Iterator __tmp = *this; |
7542 | ++*this; |
7543 | return __tmp; |
7544 | } |
7545 | |
7546 | constexpr _Iterator& |
7547 | operator--() |
7548 | requires _S_ref_is_glvalue |
7549 | && bidirectional_range<_Base> |
7550 | && __detail::__bidirectional_common<_InnerBase> |
7551 | && __detail::__bidirectional_common<_PatternBase> |
7552 | { |
7553 | if (_M_outer_it == ranges::end(_M_parent->_M_base)) |
7554 | { |
7555 | auto&& __inner = *--_M_outer_it; |
7556 | _M_inner_it.template emplace<1>(ranges::end(__inner)); |
7557 | } |
7558 | |
7559 | while (true) |
7560 | { |
7561 | if (_M_inner_it.index() == 0) |
7562 | { |
7563 | auto& __it = std::get<0>(_M_inner_it); |
7564 | if (__it == ranges::begin(_M_parent->_M_pattern)) |
7565 | { |
7566 | auto&& __inner = *--_M_outer_it; |
7567 | _M_inner_it.template emplace<1>(ranges::end(__inner)); |
7568 | } |
7569 | else |
7570 | break; |
7571 | } |
7572 | else |
7573 | { |
7574 | auto& __it = std::get<1>(_M_inner_it); |
7575 | auto&& __inner = *_M_outer_it; |
7576 | if (__it == ranges::begin(__inner)) |
7577 | _M_inner_it.template emplace<0>(ranges::end(_M_parent->_M_pattern)); |
7578 | else |
7579 | break; |
7580 | } |
7581 | } |
7582 | |
7583 | if (_M_inner_it.index() == 0) |
7584 | --std::get<0>(_M_inner_it); |
7585 | else |
7586 | --std::get<1>(_M_inner_it); |
7587 | return *this; |
7588 | } |
7589 | |
7590 | constexpr _Iterator |
7591 | operator--(int) |
7592 | requires _S_ref_is_glvalue && bidirectional_range<_Base> |
7593 | && __detail::__bidirectional_common<_InnerBase> |
7594 | && __detail::__bidirectional_common<_PatternBase> |
7595 | { |
7596 | _Iterator __tmp = *this; |
7597 | --*this; |
7598 | return __tmp; |
7599 | } |
7600 | |
7601 | friend constexpr bool |
7602 | operator==(const _Iterator& __x, const _Iterator& __y) |
7603 | requires _S_ref_is_glvalue |
7604 | && forward_range<_Base> && equality_comparable<_InnerIter> |
7605 | { return __x._M_outer_it == __y._M_outer_it && __x._M_inner_it ==__y._M_inner_it; } |
7606 | |
7607 | friend constexpr common_reference_t<iter_rvalue_reference_t<_InnerIter>, |
7608 | iter_rvalue_reference_t<_PatternIter>> |
7609 | iter_move(const _Iterator& __x) |
7610 | { |
7611 | if (__x._M_inner_it.index() == 0) |
7612 | return ranges::iter_move(std::get<0>(__x._M_inner_it)); |
7613 | else |
7614 | return ranges::iter_move(std::get<1>(__x._M_inner_it)); |
7615 | } |
7616 | |
7617 | friend constexpr void |
7618 | iter_swap(const _Iterator& __x, const _Iterator& __y) |
7619 | requires indirectly_swappable<_InnerIter, _PatternIter> |
7620 | { |
7621 | if (__x._M_inner_it.index() == 0) |
7622 | { |
7623 | if (__y._M_inner_it.index() == 0) |
7624 | ranges::iter_swap(std::get<0>(__x._M_inner_it), std::get<0>(__y._M_inner_it)); |
7625 | else |
7626 | ranges::iter_swap(std::get<0>(__x._M_inner_it), std::get<1>(__y._M_inner_it)); |
7627 | } |
7628 | else |
7629 | { |
7630 | if (__y._M_inner_it.index() == 0) |
7631 | ranges::iter_swap(std::get<1>(__x._M_inner_it), std::get<0>(__y._M_inner_it)); |
7632 | else |
7633 | ranges::iter_swap(std::get<1>(__x._M_inner_it), std::get<1>(__y._M_inner_it)); |
7634 | } |
7635 | } |
7636 | }; |
7637 | |
7638 | template<input_range _Vp, forward_range _Pattern> |
7639 | requires view<_Vp> && view<_Pattern> |
7640 | && input_range<range_reference_t<_Vp>> |
7641 | && __detail::__compatible_joinable_ranges<range_reference_t<_Vp>, _Pattern> |
7642 | template<bool _Const> |
7643 | class join_with_view<_Vp, _Pattern>::_Sentinel |
7644 | { |
7645 | using _Parent = __detail::__maybe_const_t<_Const, join_with_view>; |
7646 | using _Base = join_with_view::_Base<_Const>; |
7647 | |
7648 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
7649 | |
7650 | constexpr explicit |
7651 | _Sentinel(_Parent& __parent) |
7652 | : _M_end(ranges::end(__parent._M_base)) |
7653 | { } |
7654 | |
7655 | friend join_with_view; |
7656 | |
7657 | public: |
7658 | _Sentinel() = default; |
7659 | |
7660 | constexpr |
7661 | _Sentinel(_Sentinel<!_Const> __s) |
7662 | requires _Const && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
7663 | : _M_end(std::move(__s._M_end)) |
7664 | { } |
7665 | |
7666 | template<bool _OtherConst> |
7667 | requires sentinel_for<sentinel_t<_Base>, |
7668 | iterator_t<__detail::__maybe_const_t<_OtherConst, _Vp>>> |
7669 | friend constexpr bool |
7670 | operator==(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
7671 | { return __x._M_get_outer() == __y._M_end; } |
7672 | }; |
7673 | |
7674 | namespace views |
7675 | { |
7676 | namespace __detail |
7677 | { |
7678 | template<typename _Range, typename _Pattern> |
7679 | concept __can_join_with_view |
7680 | = requires { join_with_view(std::declval<_Range>(), std::declval<_Pattern>()); }; |
7681 | } // namespace __detail |
7682 | |
7683 | struct _JoinWith : __adaptor::_RangeAdaptor<_JoinWith> |
7684 | { |
7685 | template<viewable_range _Range, typename _Pattern> |
7686 | requires __detail::__can_join_with_view<_Range, _Pattern> |
7687 | constexpr auto |
7688 | operator() [[nodiscard]] (_Range&& __r, _Pattern&& __f) const |
7689 | { |
7690 | return join_with_view(std::forward<_Range>(__r), std::forward<_Pattern>(__f)); |
7691 | } |
7692 | |
7693 | using _RangeAdaptor<_JoinWith>::operator(); |
7694 | static constexpr int _S_arity = 2; |
7695 | template<typename _Pattern> |
7696 | static constexpr bool |
7697 | = _LazySplit::_S_has_simple_extra_args<_Pattern>; |
7698 | }; |
7699 | |
7700 | inline constexpr _JoinWith join_with; |
7701 | } // namespace views |
7702 | #endif // __cpp_lib_ranges_join_with |
7703 | |
7704 | #ifdef __cpp_lib_ranges_repeat // C++ >= 23 |
7705 | template<move_constructible _Tp, semiregular _Bound = unreachable_sentinel_t> |
7706 | requires is_object_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>> |
7707 | && (__detail::__is_integer_like<_Bound> || same_as<_Bound, unreachable_sentinel_t>) |
7708 | class repeat_view : public view_interface<repeat_view<_Tp, _Bound>> |
7709 | { |
7710 | __detail::__box<_Tp> _M_value; |
7711 | [[no_unique_address]] _Bound _M_bound = _Bound(); |
7712 | |
7713 | struct _Iterator; |
7714 | |
7715 | template<typename _Range> |
7716 | friend constexpr auto |
7717 | views::__detail::__take_of_repeat_view(_Range&&, range_difference_t<_Range>); |
7718 | |
7719 | template<typename _Range> |
7720 | friend constexpr auto |
7721 | views::__detail::__drop_of_repeat_view(_Range&&, range_difference_t<_Range>); |
7722 | |
7723 | public: |
7724 | repeat_view() requires default_initializable<_Tp> = default; |
7725 | |
7726 | constexpr explicit |
7727 | repeat_view(const _Tp& __value, _Bound __bound = _Bound()) |
7728 | requires copy_constructible<_Tp> |
7729 | : _M_value(__value), _M_bound(__bound) |
7730 | { |
7731 | if constexpr (!same_as<_Bound, unreachable_sentinel_t>) |
7732 | __glibcxx_assert(__bound >= 0); |
7733 | } |
7734 | |
7735 | constexpr explicit |
7736 | repeat_view(_Tp&& __value, _Bound __bound = _Bound()) |
7737 | : _M_value(std::move(__value)), _M_bound(__bound) |
7738 | { } |
7739 | |
7740 | template<typename... _Args, typename... _BoundArgs> |
7741 | requires constructible_from<_Tp, _Args...> |
7742 | && constructible_from<_Bound, _BoundArgs...> |
7743 | constexpr explicit |
7744 | repeat_view(piecewise_construct_t, |
7745 | tuple<_Args...> __args, |
7746 | tuple<_BoundArgs...> __bound_args = tuple<>{}) |
7747 | : _M_value(std::make_from_tuple<_Tp>(std::move(__args))), |
7748 | _M_bound(std::make_from_tuple<_Bound>(std::move(__bound_args))) |
7749 | { } |
7750 | |
7751 | constexpr _Iterator |
7752 | begin() const |
7753 | { return _Iterator(std::__addressof(*_M_value)); } |
7754 | |
7755 | constexpr _Iterator |
7756 | end() const requires (!same_as<_Bound, unreachable_sentinel_t>) |
7757 | { return _Iterator(std::__addressof(*_M_value), _M_bound); } |
7758 | |
7759 | constexpr unreachable_sentinel_t |
7760 | end() const noexcept |
7761 | { return unreachable_sentinel; } |
7762 | |
7763 | constexpr auto |
7764 | size() const requires (!same_as<_Bound, unreachable_sentinel_t>) |
7765 | { return __detail::__to_unsigned_like(_M_bound); } |
7766 | }; |
7767 | |
7768 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
7769 | // 4053. Unary call to std::views::repeat does not decay the argument |
7770 | template<typename _Tp, typename _Bound = unreachable_sentinel_t> |
7771 | repeat_view(_Tp, _Bound = _Bound()) -> repeat_view<_Tp, _Bound>; |
7772 | |
7773 | template<move_constructible _Tp, semiregular _Bound> |
7774 | requires is_object_v<_Tp> && same_as<_Tp, remove_cv_t<_Tp>> |
7775 | && (__detail::__is_integer_like<_Bound> || same_as<_Bound, unreachable_sentinel_t>) |
7776 | class repeat_view<_Tp, _Bound>::_Iterator |
7777 | { |
7778 | using __index_type |
7779 | = __conditional_t<same_as<_Bound, unreachable_sentinel_t>, ptrdiff_t, _Bound>; |
7780 | |
7781 | const _Tp* _M_value = nullptr; |
7782 | __index_type _M_current = __index_type(); |
7783 | |
7784 | constexpr explicit |
7785 | _Iterator(const _Tp* __value, __index_type __bound = __index_type()) |
7786 | : _M_value(__value), _M_current(__bound) |
7787 | { |
7788 | if constexpr (!same_as<_Bound, unreachable_sentinel_t>) |
7789 | __glibcxx_assert(__bound >= 0); |
7790 | } |
7791 | |
7792 | friend repeat_view; |
7793 | |
7794 | public: |
7795 | using iterator_concept = random_access_iterator_tag; |
7796 | using iterator_category = random_access_iterator_tag; |
7797 | using value_type = _Tp; |
7798 | using difference_type = __conditional_t<__detail::__is_signed_integer_like<__index_type>, |
7799 | __index_type, |
7800 | __detail::__iota_diff_t<__index_type>>; |
7801 | |
7802 | _Iterator() = default; |
7803 | |
7804 | constexpr const _Tp& |
7805 | operator*() const noexcept |
7806 | { return *_M_value; } |
7807 | |
7808 | constexpr _Iterator& |
7809 | operator++() |
7810 | { |
7811 | ++_M_current; |
7812 | return *this; |
7813 | } |
7814 | |
7815 | constexpr _Iterator |
7816 | operator++(int) |
7817 | { |
7818 | auto __tmp = *this; |
7819 | ++*this; |
7820 | return __tmp; |
7821 | } |
7822 | |
7823 | constexpr _Iterator& |
7824 | operator--() |
7825 | { |
7826 | if constexpr (!same_as<_Bound, unreachable_sentinel_t>) |
7827 | __glibcxx_assert(_M_current > 0); |
7828 | --_M_current; |
7829 | return *this; |
7830 | } |
7831 | |
7832 | constexpr _Iterator |
7833 | operator--(int) |
7834 | { |
7835 | auto __tmp = *this; |
7836 | --*this; |
7837 | return __tmp; |
7838 | } |
7839 | |
7840 | constexpr _Iterator& |
7841 | operator+=(difference_type __n) |
7842 | { |
7843 | if constexpr (!same_as<_Bound, unreachable_sentinel_t>) |
7844 | __glibcxx_assert(_M_current + __n >= 0); |
7845 | _M_current += __n; |
7846 | return *this; |
7847 | } |
7848 | |
7849 | constexpr _Iterator& |
7850 | operator-=(difference_type __n) |
7851 | { |
7852 | if constexpr (!same_as<_Bound, unreachable_sentinel_t>) |
7853 | __glibcxx_assert(_M_current - __n >= 0); |
7854 | _M_current -= __n; |
7855 | return *this; |
7856 | } |
7857 | |
7858 | constexpr const _Tp& |
7859 | operator[](difference_type __n) const noexcept |
7860 | { return *(*this + __n); } |
7861 | |
7862 | friend constexpr bool |
7863 | operator==(const _Iterator& __x, const _Iterator& __y) |
7864 | { return __x._M_current == __y._M_current; } |
7865 | |
7866 | friend constexpr auto |
7867 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
7868 | { return __x._M_current <=> __y._M_current; } |
7869 | |
7870 | friend constexpr _Iterator |
7871 | operator+(_Iterator __i, difference_type __n) |
7872 | { |
7873 | __i += __n; |
7874 | return __i; |
7875 | } |
7876 | |
7877 | friend constexpr _Iterator |
7878 | operator+(difference_type __n, _Iterator __i) |
7879 | { return __i + __n; } |
7880 | |
7881 | friend constexpr _Iterator |
7882 | operator-(_Iterator __i, difference_type __n) |
7883 | { |
7884 | __i -= __n; |
7885 | return __i; |
7886 | } |
7887 | |
7888 | friend constexpr difference_type |
7889 | operator-(const _Iterator& __x, const _Iterator& __y) |
7890 | { |
7891 | return (static_cast<difference_type>(__x._M_current) |
7892 | - static_cast<difference_type>(__y._M_current)); |
7893 | } |
7894 | }; |
7895 | |
7896 | namespace views |
7897 | { |
7898 | namespace __detail |
7899 | { |
7900 | template<typename _Tp, typename _Bound> |
7901 | inline constexpr bool __is_repeat_view<repeat_view<_Tp, _Bound>> = true; |
7902 | |
7903 | template<typename _Tp> |
7904 | concept __can_repeat_view |
7905 | = requires { repeat_view(std::declval<_Tp>()); }; |
7906 | |
7907 | template<typename _Tp, typename _Bound> |
7908 | concept __can_bounded_repeat_view |
7909 | = requires { repeat_view(std::declval<_Tp>(), std::declval<_Bound>()); }; |
7910 | } |
7911 | |
7912 | struct _Repeat |
7913 | { |
7914 | template<typename _Tp> |
7915 | requires __detail::__can_repeat_view<_Tp> |
7916 | constexpr auto |
7917 | operator() [[nodiscard]] (_Tp&& __value) const |
7918 | { |
7919 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
7920 | // 4054. Repeating a repeat_view should repeat the view |
7921 | return repeat_view<decay_t<_Tp>>(std::forward<_Tp>(__value)); |
7922 | } |
7923 | |
7924 | template<typename _Tp, typename _Bound> |
7925 | requires __detail::__can_bounded_repeat_view<_Tp, _Bound> |
7926 | constexpr auto |
7927 | operator() [[nodiscard]] (_Tp&& __value, _Bound __bound) const |
7928 | { return repeat_view(std::forward<_Tp>(__value), __bound); } |
7929 | }; |
7930 | |
7931 | inline constexpr _Repeat repeat; |
7932 | |
7933 | namespace __detail |
7934 | { |
7935 | template<typename _Range> |
7936 | constexpr auto |
7937 | __take_of_repeat_view(_Range&& __r, range_difference_t<_Range> __n) |
7938 | { |
7939 | using _Tp = remove_cvref_t<_Range>; |
7940 | static_assert(__is_repeat_view<_Tp>); |
7941 | if constexpr (sized_range<_Tp>) |
7942 | return views::repeat(*std::forward<_Range>(__r)._M_value, |
7943 | std::min(ranges::distance(__r), __n)); |
7944 | else |
7945 | return views::repeat(*std::forward<_Range>(__r)._M_value, __n); |
7946 | } |
7947 | |
7948 | template<typename _Range> |
7949 | constexpr auto |
7950 | __drop_of_repeat_view(_Range&& __r, range_difference_t<_Range> __n) |
7951 | { |
7952 | using _Tp = remove_cvref_t<_Range>; |
7953 | static_assert(__is_repeat_view<_Tp>); |
7954 | if constexpr (sized_range<_Tp>) |
7955 | { |
7956 | auto __sz = ranges::distance(__r); |
7957 | return views::repeat(*std::forward<_Range>(__r)._M_value, |
7958 | __sz - std::min(__sz, __n)); |
7959 | } |
7960 | else |
7961 | return __r; |
7962 | } |
7963 | } |
7964 | } |
7965 | #endif // __cpp_lib_ranges_repeat |
7966 | |
7967 | #ifdef __cpp_lib_ranges_stride // C++ >= 23 |
7968 | template<input_range _Vp> |
7969 | requires view<_Vp> |
7970 | class stride_view : public view_interface<stride_view<_Vp>> |
7971 | { |
7972 | _Vp _M_base; |
7973 | range_difference_t<_Vp> _M_stride; |
7974 | |
7975 | template<bool _Const> using _Base = __detail::__maybe_const_t<_Const, _Vp>; |
7976 | |
7977 | template<bool _Const> |
7978 | struct __iter_cat |
7979 | { }; |
7980 | |
7981 | template<bool _Const> |
7982 | requires forward_range<_Base<_Const>> |
7983 | struct __iter_cat<_Const> |
7984 | { |
7985 | private: |
7986 | static auto |
7987 | _S_iter_cat() |
7988 | { |
7989 | using _Cat = typename iterator_traits<iterator_t<_Base<_Const>>>::iterator_category; |
7990 | if constexpr (derived_from<_Cat, random_access_iterator_tag>) |
7991 | return random_access_iterator_tag{}; |
7992 | else |
7993 | return _Cat{}; |
7994 | } |
7995 | public: |
7996 | using iterator_category = decltype(_S_iter_cat()); |
7997 | }; |
7998 | |
7999 | template<bool> class _Iterator; |
8000 | |
8001 | public: |
8002 | constexpr explicit |
8003 | stride_view(_Vp __base, range_difference_t<_Vp> __stride) |
8004 | : _M_base(std::move(__base)), _M_stride(__stride) |
8005 | { __glibcxx_assert(__stride > 0); } |
8006 | |
8007 | constexpr _Vp |
8008 | base() const& requires copy_constructible<_Vp> |
8009 | { return _M_base; } |
8010 | |
8011 | constexpr _Vp |
8012 | base() && |
8013 | { return std::move(_M_base); } |
8014 | |
8015 | constexpr range_difference_t<_Vp> |
8016 | stride() const noexcept |
8017 | { return _M_stride; } |
8018 | |
8019 | constexpr auto |
8020 | begin() requires (!__detail::__simple_view<_Vp>) |
8021 | { return _Iterator<false>(this, ranges::begin(_M_base)); } |
8022 | |
8023 | constexpr auto |
8024 | begin() const requires range<const _Vp> |
8025 | { return _Iterator<true>(this, ranges::begin(_M_base)); } |
8026 | |
8027 | constexpr auto |
8028 | end() requires (!__detail::__simple_view<_Vp>) |
8029 | { |
8030 | if constexpr (common_range<_Vp> && sized_range<_Vp> && forward_range<_Vp>) |
8031 | { |
8032 | auto __missing = (_M_stride - ranges::distance(_M_base) % _M_stride) % _M_stride; |
8033 | return _Iterator<false>(this, ranges::end(_M_base), __missing); |
8034 | } |
8035 | else if constexpr (common_range<_Vp> && !bidirectional_range<_Vp>) |
8036 | return _Iterator<false>(this, ranges::end(_M_base)); |
8037 | else |
8038 | return default_sentinel; |
8039 | } |
8040 | |
8041 | constexpr auto |
8042 | end() const requires range<const _Vp> |
8043 | { |
8044 | if constexpr (common_range<const _Vp> && sized_range<const _Vp> |
8045 | && forward_range<const _Vp>) |
8046 | { |
8047 | auto __missing = (_M_stride - ranges::distance(_M_base) % _M_stride) % _M_stride; |
8048 | return _Iterator<true>(this, ranges::end(_M_base), __missing); |
8049 | } |
8050 | else if constexpr (common_range<const _Vp> && !bidirectional_range<const _Vp>) |
8051 | return _Iterator<true>(this, ranges::end(_M_base)); |
8052 | else |
8053 | return default_sentinel; |
8054 | } |
8055 | |
8056 | constexpr auto |
8057 | size() requires sized_range<_Vp> |
8058 | { |
8059 | return __detail::__to_unsigned_like |
8060 | (__detail::__div_ceil(ranges::distance(_M_base), _M_stride)); |
8061 | } |
8062 | |
8063 | constexpr auto |
8064 | size() const requires sized_range<const _Vp> |
8065 | { |
8066 | return __detail::__to_unsigned_like |
8067 | (__detail::__div_ceil(ranges::distance(_M_base), _M_stride)); |
8068 | } |
8069 | }; |
8070 | |
8071 | template<typename _Range> |
8072 | stride_view(_Range&&, range_difference_t<_Range>) -> stride_view<views::all_t<_Range>>; |
8073 | |
8074 | template<typename _Vp> |
8075 | inline constexpr bool enable_borrowed_range<stride_view<_Vp>> |
8076 | = enable_borrowed_range<_Vp>; |
8077 | |
8078 | template<input_range _Vp> |
8079 | requires view<_Vp> |
8080 | template<bool _Const> |
8081 | class stride_view<_Vp>::_Iterator : public __iter_cat<_Const> |
8082 | { |
8083 | using _Parent = __detail::__maybe_const_t<_Const, stride_view>; |
8084 | using _Base = stride_view::_Base<_Const>; |
8085 | |
8086 | iterator_t<_Base> _M_current = iterator_t<_Base>(); |
8087 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
8088 | range_difference_t<_Base> _M_stride = 0; |
8089 | range_difference_t<_Base> _M_missing = 0; |
8090 | |
8091 | constexpr |
8092 | _Iterator(_Parent* __parent, iterator_t<_Base> __current, |
8093 | range_difference_t<_Base> __missing = 0) |
8094 | : _M_current(std::move(__current)), _M_end(ranges::end(__parent->_M_base)), |
8095 | _M_stride(__parent->_M_stride), _M_missing(__missing) |
8096 | { } |
8097 | |
8098 | static auto |
8099 | _S_iter_concept() |
8100 | { |
8101 | if constexpr (random_access_range<_Base>) |
8102 | return random_access_iterator_tag{}; |
8103 | else if constexpr (bidirectional_range<_Base>) |
8104 | return bidirectional_iterator_tag{}; |
8105 | else if constexpr (forward_range<_Base>) |
8106 | return forward_iterator_tag{}; |
8107 | else |
8108 | return input_iterator_tag{}; |
8109 | } |
8110 | |
8111 | friend stride_view; |
8112 | |
8113 | public: |
8114 | using difference_type = range_difference_t<_Base>; |
8115 | using value_type = range_value_t<_Base>; |
8116 | using iterator_concept = decltype(_S_iter_concept()); |
8117 | // iterator_category defined in stride_view::__iter_cat |
8118 | |
8119 | _Iterator() requires default_initializable<iterator_t<_Base>> = default; |
8120 | |
8121 | constexpr |
8122 | _Iterator(_Iterator<!_Const> __other) |
8123 | requires _Const |
8124 | && convertible_to<iterator_t<_Vp>, iterator_t<_Base>> |
8125 | && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
8126 | : _M_current(std::move(__other._M_current)), _M_end(std::move(__other._M_end)), |
8127 | _M_stride(__other._M_stride), _M_missing(__other._M_missing) |
8128 | { } |
8129 | |
8130 | constexpr iterator_t<_Base> |
8131 | base() && |
8132 | { return std::move(_M_current); } |
8133 | |
8134 | constexpr const iterator_t<_Base>& |
8135 | base() const & noexcept |
8136 | { return _M_current; } |
8137 | |
8138 | constexpr decltype(auto) |
8139 | operator*() const |
8140 | { return *_M_current; } |
8141 | |
8142 | constexpr _Iterator& |
8143 | operator++() |
8144 | { |
8145 | __glibcxx_assert(_M_current != _M_end); |
8146 | _M_missing = ranges::advance(_M_current, _M_stride, _M_end); |
8147 | return *this; |
8148 | } |
8149 | |
8150 | constexpr void |
8151 | operator++(int) |
8152 | { ++*this; } |
8153 | |
8154 | constexpr _Iterator |
8155 | operator++(int) requires forward_range<_Base> |
8156 | { |
8157 | auto __tmp = *this; |
8158 | ++*this; |
8159 | return __tmp; |
8160 | } |
8161 | |
8162 | constexpr _Iterator& |
8163 | operator--() requires bidirectional_range<_Base> |
8164 | { |
8165 | ranges::advance(_M_current, _M_missing - _M_stride); |
8166 | _M_missing = 0; |
8167 | return *this; |
8168 | } |
8169 | |
8170 | constexpr _Iterator |
8171 | operator--(int) requires bidirectional_range<_Base> |
8172 | { |
8173 | auto __tmp = *this; |
8174 | --*this; |
8175 | return __tmp; |
8176 | } |
8177 | |
8178 | constexpr _Iterator& |
8179 | operator+=(difference_type __n) requires random_access_range<_Base> |
8180 | { |
8181 | if (__n > 0) |
8182 | { |
8183 | __glibcxx_assert(ranges::distance(_M_current, _M_end) > _M_stride * (__n - 1)); |
8184 | _M_missing = ranges::advance(_M_current, _M_stride * __n, _M_end); |
8185 | } |
8186 | else if (__n < 0) |
8187 | { |
8188 | ranges::advance(_M_current, _M_stride * __n + _M_missing); |
8189 | _M_missing = 0; |
8190 | } |
8191 | return *this; |
8192 | } |
8193 | |
8194 | constexpr _Iterator& |
8195 | operator-=(difference_type __n) requires random_access_range<_Base> |
8196 | { return *this += -__n; } |
8197 | |
8198 | constexpr decltype(auto) operator[](difference_type __n) const |
8199 | requires random_access_range<_Base> |
8200 | { return *(*this + __n); } |
8201 | |
8202 | friend constexpr bool |
8203 | operator==(const _Iterator& __x, default_sentinel_t) |
8204 | { return __x._M_current == __x._M_end; } |
8205 | |
8206 | friend constexpr bool |
8207 | operator==(const _Iterator& __x, const _Iterator& __y) |
8208 | requires equality_comparable<iterator_t<_Base>> |
8209 | { return __x._M_current == __y._M_current; } |
8210 | |
8211 | friend constexpr bool |
8212 | operator<(const _Iterator& __x, const _Iterator& __y) |
8213 | requires random_access_range<_Base> |
8214 | { return __x._M_current < __y._M_current; } |
8215 | |
8216 | friend constexpr bool |
8217 | operator>(const _Iterator& __x, const _Iterator& __y) |
8218 | requires random_access_range<_Base> |
8219 | { return __y._M_current < __x._M_current; } |
8220 | |
8221 | friend constexpr bool |
8222 | operator<=(const _Iterator& __x, const _Iterator& __y) |
8223 | requires random_access_range<_Base> |
8224 | { return !(__y._M_current < __x._M_current); } |
8225 | |
8226 | friend constexpr bool |
8227 | operator>=(const _Iterator& __x, const _Iterator& __y) |
8228 | requires random_access_range<_Base> |
8229 | { return !(__x._M_current < __y._M_current); } |
8230 | |
8231 | friend constexpr auto |
8232 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
8233 | requires random_access_range<_Base> && three_way_comparable<iterator_t<_Base>> |
8234 | { return __x._M_current <=> __y._M_current; } |
8235 | |
8236 | friend constexpr _Iterator |
8237 | operator+(const _Iterator& __i, difference_type __n) |
8238 | requires random_access_range<_Base> |
8239 | { |
8240 | auto __r = __i; |
8241 | __r += __n; |
8242 | return __r; |
8243 | } |
8244 | |
8245 | friend constexpr _Iterator |
8246 | operator+(difference_type __n, const _Iterator& __i) |
8247 | requires random_access_range<_Base> |
8248 | { return __i + __n; } |
8249 | |
8250 | friend constexpr _Iterator |
8251 | operator-(const _Iterator& __i, difference_type __n) |
8252 | requires random_access_range<_Base> |
8253 | { |
8254 | auto __r = __i; |
8255 | __r -= __n; |
8256 | return __r; |
8257 | } |
8258 | |
8259 | friend constexpr difference_type |
8260 | operator-(const _Iterator& __x, const _Iterator& __y) |
8261 | requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>> |
8262 | { |
8263 | auto __n = __x._M_current - __y._M_current; |
8264 | if constexpr (forward_range<_Base>) |
8265 | return (__n + __x._M_missing - __y._M_missing) / __x._M_stride; |
8266 | else if (__n < 0) |
8267 | return -__detail::__div_ceil(-__n, __x._M_stride); |
8268 | else |
8269 | return __detail::__div_ceil(__n, __x._M_stride); |
8270 | } |
8271 | |
8272 | friend constexpr difference_type |
8273 | operator-(default_sentinel_t __y, const _Iterator& __x) |
8274 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base>> |
8275 | { return __detail::__div_ceil(__x._M_end - __x._M_current, __x._M_stride); } |
8276 | |
8277 | friend constexpr difference_type |
8278 | operator-(const _Iterator& __x, default_sentinel_t __y) |
8279 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base>> |
8280 | { return -(__y - __x); } |
8281 | |
8282 | friend constexpr range_rvalue_reference_t<_Base> |
8283 | iter_move(const _Iterator& __i) |
8284 | noexcept(noexcept(ranges::iter_move(__i._M_current))) |
8285 | { return ranges::iter_move(__i._M_current); } |
8286 | |
8287 | friend constexpr void |
8288 | iter_swap(const _Iterator& __x, const _Iterator& __y) |
8289 | noexcept(noexcept(ranges::iter_swap(__x._M_current, __y._M_current))) |
8290 | requires indirectly_swappable<iterator_t<_Base>> |
8291 | { ranges::iter_swap(__x._M_current, __y._M_current); } |
8292 | }; |
8293 | |
8294 | namespace views |
8295 | { |
8296 | namespace __detail |
8297 | { |
8298 | template<typename _Range, typename _Dp> |
8299 | concept __can_stride_view |
8300 | = requires { stride_view(std::declval<_Range>(), std::declval<_Dp>()); }; |
8301 | } |
8302 | |
8303 | struct _Stride : __adaptor::_RangeAdaptor<_Stride> |
8304 | { |
8305 | template<viewable_range _Range, typename _Dp = range_difference_t<_Range>> |
8306 | requires __detail::__can_stride_view<_Range, _Dp> |
8307 | constexpr auto |
8308 | operator() [[nodiscard]] (_Range&& __r, type_identity_t<_Dp> __n) const |
8309 | { return stride_view(std::forward<_Range>(__r), __n); } |
8310 | |
8311 | using __adaptor::_RangeAdaptor<_Stride>::operator(); |
8312 | static constexpr int _S_arity = 2; |
8313 | static constexpr bool = true; |
8314 | }; |
8315 | |
8316 | inline constexpr _Stride stride; |
8317 | } |
8318 | #endif // __cpp_lib_ranges_stride |
8319 | |
8320 | #ifdef __cpp_lib_ranges_cartesian_product // C++ >= 23 |
8321 | namespace __detail |
8322 | { |
8323 | template<bool _Const, typename _First, typename... _Vs> |
8324 | concept __cartesian_product_is_random_access |
8325 | = (random_access_range<__maybe_const_t<_Const, _First>> |
8326 | && ... |
8327 | && (random_access_range<__maybe_const_t<_Const, _Vs>> |
8328 | && sized_range<__maybe_const_t<_Const, _Vs>>)); |
8329 | |
8330 | template<typename _Range> |
8331 | concept __cartesian_product_common_arg |
8332 | = common_range<_Range> || (sized_range<_Range> && random_access_range<_Range>); |
8333 | |
8334 | template<bool _Const, typename _First, typename... _Vs> |
8335 | concept __cartesian_product_is_bidirectional |
8336 | = (bidirectional_range<__maybe_const_t<_Const, _First>> |
8337 | && ... |
8338 | && (bidirectional_range<__maybe_const_t<_Const, _Vs>> |
8339 | && __cartesian_product_common_arg<__maybe_const_t<_Const, _Vs>>)); |
8340 | |
8341 | template<typename _First, typename... _Vs> |
8342 | concept __cartesian_product_is_common = __cartesian_product_common_arg<_First>; |
8343 | |
8344 | template<typename... _Vs> |
8345 | concept __cartesian_product_is_sized = (sized_range<_Vs> && ...); |
8346 | |
8347 | template<bool _Const, template<typename> class FirstSent, typename _First, typename... _Vs> |
8348 | concept __cartesian_is_sized_sentinel |
8349 | = (sized_sentinel_for<FirstSent<__maybe_const_t<_Const, _First>>, |
8350 | iterator_t<__maybe_const_t<_Const, _First>>> |
8351 | && ... |
8352 | && (sized_range<__maybe_const_t<_Const, _Vs>> |
8353 | && sized_sentinel_for<iterator_t<__maybe_const_t<_Const, _Vs>>, |
8354 | iterator_t<__maybe_const_t<_Const, _Vs>>>)); |
8355 | |
8356 | template<__cartesian_product_common_arg _Range> |
8357 | constexpr auto |
8358 | __cartesian_common_arg_end(_Range& __r) |
8359 | { |
8360 | if constexpr (common_range<_Range>) |
8361 | return ranges::end(__r); |
8362 | else |
8363 | return ranges::begin(__r) + ranges::distance(__r); |
8364 | } |
8365 | } // namespace __detail |
8366 | |
8367 | template<input_range _First, forward_range... _Vs> |
8368 | requires (view<_First> && ... && view<_Vs>) |
8369 | class cartesian_product_view : public view_interface<cartesian_product_view<_First, _Vs...>> |
8370 | { |
8371 | tuple<_First, _Vs...> _M_bases; |
8372 | |
8373 | template<bool> class _Iterator; |
8374 | |
8375 | static auto |
8376 | _S_difference_type() |
8377 | { |
8378 | // TODO: Implement the recommended practice of using the smallest |
8379 | // sufficiently wide type according to the maximum sizes of the |
8380 | // underlying ranges? |
8381 | return common_type_t<ptrdiff_t, |
8382 | range_difference_t<_First>, |
8383 | range_difference_t<_Vs>...>{}; |
8384 | } |
8385 | |
8386 | public: |
8387 | cartesian_product_view() = default; |
8388 | |
8389 | constexpr explicit |
8390 | cartesian_product_view(_First __first, _Vs... __rest) |
8391 | : _M_bases(std::move(__first), std::move(__rest)...) |
8392 | { } |
8393 | |
8394 | constexpr _Iterator<false> |
8395 | begin() requires (!__detail::__simple_view<_First> || ... || !__detail::__simple_view<_Vs>) |
8396 | { return _Iterator<false>(*this, __detail::__tuple_transform(ranges::begin, _M_bases)); } |
8397 | |
8398 | constexpr _Iterator<true> |
8399 | begin() const requires (range<const _First> && ... && range<const _Vs>) |
8400 | { return _Iterator<true>(*this, __detail::__tuple_transform(ranges::begin, _M_bases)); } |
8401 | |
8402 | constexpr _Iterator<false> |
8403 | end() requires ((!__detail::__simple_view<_First> || ... || !__detail::__simple_view<_Vs>) |
8404 | && __detail::__cartesian_product_is_common<_First, _Vs...>) |
8405 | { |
8406 | auto __its = [this]<size_t... _Is>(index_sequence<_Is...>) { |
8407 | using _Ret = tuple<iterator_t<_First>, iterator_t<_Vs>...>; |
8408 | bool __empty_tail = (ranges::empty(std::get<1 + _Is>(_M_bases)) || ...); |
8409 | auto& __first = std::get<0>(_M_bases); |
8410 | return _Ret{(__empty_tail |
8411 | ? ranges::begin(__first) |
8412 | : __detail::__cartesian_common_arg_end(__first)), |
8413 | ranges::begin(std::get<1 + _Is>(_M_bases))...}; |
8414 | }(make_index_sequence<sizeof...(_Vs)>{}); |
8415 | |
8416 | return _Iterator<false>{*this, std::move(__its)}; |
8417 | } |
8418 | |
8419 | constexpr _Iterator<true> |
8420 | end() const requires __detail::__cartesian_product_is_common<const _First, const _Vs...> |
8421 | { |
8422 | auto __its = [this]<size_t... _Is>(index_sequence<_Is...>) { |
8423 | using _Ret = tuple<iterator_t<const _First>, iterator_t<const _Vs>...>; |
8424 | bool __empty_tail = (ranges::empty(std::get<1 + _Is>(_M_bases)) || ...); |
8425 | auto& __first = std::get<0>(_M_bases); |
8426 | return _Ret{(__empty_tail |
8427 | ? ranges::begin(__first) |
8428 | : __detail::__cartesian_common_arg_end(__first)), |
8429 | ranges::begin(std::get<1 + _Is>(_M_bases))...}; |
8430 | }(make_index_sequence<sizeof...(_Vs)>{}); |
8431 | |
8432 | return _Iterator<true>{*this, std::move(__its)}; |
8433 | } |
8434 | |
8435 | constexpr default_sentinel_t |
8436 | end() const noexcept |
8437 | { return default_sentinel; } |
8438 | |
8439 | constexpr auto |
8440 | size() requires __detail::__cartesian_product_is_sized<_First, _Vs...> |
8441 | { |
8442 | using _ST = __detail::__make_unsigned_like_t<decltype(_S_difference_type())>; |
8443 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
8444 | auto __size = static_cast<_ST>(1); |
8445 | #ifdef _GLIBCXX_ASSERTIONS |
8446 | if constexpr (integral<_ST>) |
8447 | { |
8448 | bool __overflow |
8449 | = (__builtin_mul_overflow(__size, |
8450 | static_cast<_ST>(ranges::size(std::get<_Is>(_M_bases))), |
8451 | &__size) |
8452 | || ...); |
8453 | __glibcxx_assert(!__overflow); |
8454 | } |
8455 | else |
8456 | #endif |
8457 | __size = (static_cast<_ST>(ranges::size(std::get<_Is>(_M_bases))) * ...); |
8458 | return __size; |
8459 | }(make_index_sequence<1 + sizeof...(_Vs)>{}); |
8460 | } |
8461 | |
8462 | constexpr auto |
8463 | size() const requires __detail::__cartesian_product_is_sized<const _First, const _Vs...> |
8464 | { |
8465 | using _ST = __detail::__make_unsigned_like_t<decltype(_S_difference_type())>; |
8466 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
8467 | auto __size = static_cast<_ST>(1); |
8468 | #ifdef _GLIBCXX_ASSERTIONS |
8469 | if constexpr (integral<_ST>) |
8470 | { |
8471 | bool __overflow |
8472 | = (__builtin_mul_overflow(__size, |
8473 | static_cast<_ST>(ranges::size(std::get<_Is>(_M_bases))), |
8474 | &__size) |
8475 | || ...); |
8476 | __glibcxx_assert(!__overflow); |
8477 | } |
8478 | else |
8479 | #endif |
8480 | __size = (static_cast<_ST>(ranges::size(std::get<_Is>(_M_bases))) * ...); |
8481 | return __size; |
8482 | }(make_index_sequence<1 + sizeof...(_Vs)>{}); |
8483 | } |
8484 | }; |
8485 | |
8486 | template<typename... _Vs> |
8487 | cartesian_product_view(_Vs&&...) -> cartesian_product_view<views::all_t<_Vs>...>; |
8488 | |
8489 | template<input_range _First, forward_range... _Vs> |
8490 | requires (view<_First> && ... && view<_Vs>) |
8491 | template<bool _Const> |
8492 | class cartesian_product_view<_First, _Vs...>::_Iterator |
8493 | { |
8494 | using _Parent = __maybe_const_t<_Const, cartesian_product_view>; |
8495 | _Parent* _M_parent = nullptr; |
8496 | tuple<iterator_t<__maybe_const_t<_Const, _First>>, |
8497 | iterator_t<__maybe_const_t<_Const, _Vs>>...> _M_current; |
8498 | |
8499 | constexpr |
8500 | _Iterator(_Parent& __parent, decltype(_M_current) __current) |
8501 | : _M_parent(std::__addressof(__parent)), |
8502 | _M_current(std::move(__current)) |
8503 | { } |
8504 | |
8505 | static auto |
8506 | _S_iter_concept() |
8507 | { |
8508 | if constexpr (__detail::__cartesian_product_is_random_access<_Const, _First, _Vs...>) |
8509 | return random_access_iterator_tag{}; |
8510 | else if constexpr (__detail::__cartesian_product_is_bidirectional<_Const, _First, _Vs...>) |
8511 | return bidirectional_iterator_tag{}; |
8512 | else if constexpr (forward_range<__maybe_const_t<_Const, _First>>) |
8513 | return forward_iterator_tag{}; |
8514 | else |
8515 | return input_iterator_tag{}; |
8516 | } |
8517 | |
8518 | friend cartesian_product_view; |
8519 | |
8520 | public: |
8521 | using iterator_category = input_iterator_tag; |
8522 | using iterator_concept = decltype(_S_iter_concept()); |
8523 | using value_type |
8524 | = tuple<range_value_t<__maybe_const_t<_Const, _First>>, |
8525 | range_value_t<__maybe_const_t<_Const, _Vs>>...>; |
8526 | using reference |
8527 | = tuple<range_reference_t<__maybe_const_t<_Const, _First>>, |
8528 | range_reference_t<__maybe_const_t<_Const, _Vs>>...>; |
8529 | using difference_type = decltype(cartesian_product_view::_S_difference_type()); |
8530 | |
8531 | _Iterator() = default; |
8532 | |
8533 | constexpr |
8534 | _Iterator(_Iterator<!_Const> __i) |
8535 | requires _Const |
8536 | && (convertible_to<iterator_t<_First>, iterator_t<const _First>> |
8537 | && ... && convertible_to<iterator_t<_Vs>, iterator_t<const _Vs>>) |
8538 | : _M_parent(std::__addressof(__i._M_parent)), |
8539 | _M_current(std::move(__i._M_current)) |
8540 | { } |
8541 | |
8542 | constexpr auto |
8543 | operator*() const |
8544 | { |
8545 | auto __f = [](auto& __i) -> decltype(auto) { |
8546 | return *__i; |
8547 | }; |
8548 | return __detail::__tuple_transform(__f, _M_current); |
8549 | } |
8550 | |
8551 | constexpr _Iterator& |
8552 | operator++() |
8553 | { |
8554 | _M_next(); |
8555 | return *this; |
8556 | } |
8557 | |
8558 | constexpr void |
8559 | operator++(int) |
8560 | { ++*this; } |
8561 | |
8562 | constexpr _Iterator |
8563 | operator++(int) requires forward_range<__maybe_const_t<_Const, _First>> |
8564 | { |
8565 | auto __tmp = *this; |
8566 | ++*this; |
8567 | return __tmp; |
8568 | } |
8569 | |
8570 | constexpr _Iterator& |
8571 | operator--() |
8572 | requires __detail::__cartesian_product_is_bidirectional<_Const, _First, _Vs...> |
8573 | { |
8574 | _M_prev(); |
8575 | return *this; |
8576 | } |
8577 | |
8578 | constexpr _Iterator |
8579 | operator--(int) |
8580 | requires __detail::__cartesian_product_is_bidirectional<_Const, _First, _Vs...> |
8581 | { |
8582 | auto __tmp = *this; |
8583 | --*this; |
8584 | return __tmp; |
8585 | } |
8586 | |
8587 | constexpr _Iterator& |
8588 | operator+=(difference_type __x) |
8589 | requires __detail::__cartesian_product_is_random_access<_Const, _First, _Vs...> |
8590 | { |
8591 | _M_advance(__x); |
8592 | return *this; |
8593 | } |
8594 | |
8595 | constexpr _Iterator& |
8596 | operator-=(difference_type __x) |
8597 | requires __detail::__cartesian_product_is_random_access<_Const, _First, _Vs...> |
8598 | { return *this += -__x; } |
8599 | |
8600 | constexpr reference |
8601 | operator[](difference_type __n) const |
8602 | requires __detail::__cartesian_product_is_random_access<_Const, _First, _Vs...> |
8603 | { return *((*this) + __n); } |
8604 | |
8605 | friend constexpr bool |
8606 | operator==(const _Iterator& __x, const _Iterator& __y) |
8607 | requires equality_comparable<iterator_t<__maybe_const_t<_Const, _First>>> |
8608 | { return __x._M_current == __y._M_current; } |
8609 | |
8610 | friend constexpr bool |
8611 | operator==(const _Iterator& __x, default_sentinel_t) |
8612 | { |
8613 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
8614 | return ((std::get<_Is>(__x._M_current) |
8615 | == ranges::end(std::get<_Is>(__x._M_parent->_M_bases))) |
8616 | || ...); |
8617 | }(make_index_sequence<1 + sizeof...(_Vs)>{}); |
8618 | } |
8619 | |
8620 | friend constexpr auto |
8621 | operator<=>(const _Iterator& __x, const _Iterator& __y) |
8622 | requires __detail::__all_random_access<_Const, _First, _Vs...> |
8623 | { return __x._M_current <=> __y._M_current; } |
8624 | |
8625 | friend constexpr _Iterator |
8626 | operator+(_Iterator __x, difference_type __y) |
8627 | requires __detail::__cartesian_product_is_random_access<_Const, _First, _Vs...> |
8628 | { return __x += __y; } |
8629 | |
8630 | friend constexpr _Iterator |
8631 | operator+(difference_type __x, _Iterator __y) |
8632 | requires __detail::__cartesian_product_is_random_access<_Const, _First, _Vs...> |
8633 | { return __y += __x; } |
8634 | |
8635 | friend constexpr _Iterator |
8636 | operator-(_Iterator __x, difference_type __y) |
8637 | requires __detail::__cartesian_product_is_random_access<_Const, _First, _Vs...> |
8638 | { return __x -= __y; } |
8639 | |
8640 | friend constexpr difference_type |
8641 | operator-(const _Iterator& __x, const _Iterator& __y) |
8642 | requires __detail::__cartesian_is_sized_sentinel<_Const, iterator_t, _First, _Vs...> |
8643 | { return __x._M_distance_from(__y._M_current); } |
8644 | |
8645 | friend constexpr difference_type |
8646 | operator-(const _Iterator& __i, default_sentinel_t) |
8647 | requires __detail::__cartesian_is_sized_sentinel<_Const, sentinel_t, _First, _Vs...> |
8648 | { |
8649 | tuple __end_tuple = [&]<size_t... _Is>(index_sequence<_Is...>) { |
8650 | return tuple{ranges::end(std::get<0>(__i._M_parent->_M_bases)), |
8651 | ranges::begin(std::get<1 + _Is>(__i._M_parent->_M_bases))...}; |
8652 | }(make_index_sequence<sizeof...(_Vs)>{}); |
8653 | return __i._M_distance_from(__end_tuple); |
8654 | } |
8655 | |
8656 | friend constexpr difference_type |
8657 | operator-(default_sentinel_t, const _Iterator& __i) |
8658 | requires __detail::__cartesian_is_sized_sentinel<_Const, sentinel_t, _First, _Vs...> |
8659 | { return -(__i - default_sentinel); } |
8660 | |
8661 | friend constexpr auto |
8662 | iter_move(const _Iterator& __i) |
8663 | { return __detail::__tuple_transform(ranges::iter_move, __i._M_current); } |
8664 | |
8665 | friend constexpr void |
8666 | iter_swap(const _Iterator& __l, const _Iterator& __r) |
8667 | requires (indirectly_swappable<iterator_t<__maybe_const_t<_Const, _First>>> |
8668 | && ... |
8669 | && indirectly_swappable<iterator_t<__maybe_const_t<_Const, _Vs>>>) |
8670 | { |
8671 | [&]<size_t... _Is>(index_sequence<_Is...>) { |
8672 | (ranges::iter_swap(std::get<_Is>(__l._M_current), std::get<_Is>(__r._M_current)), ...); |
8673 | }(make_index_sequence<1 + sizeof...(_Vs)>{}); |
8674 | } |
8675 | |
8676 | private: |
8677 | template<size_t _Nm = sizeof...(_Vs)> |
8678 | constexpr void |
8679 | _M_next() |
8680 | { |
8681 | auto& __it = std::get<_Nm>(_M_current); |
8682 | ++__it; |
8683 | if constexpr (_Nm > 0) |
8684 | if (__it == ranges::end(std::get<_Nm>(_M_parent->_M_bases))) |
8685 | { |
8686 | __it = ranges::begin(std::get<_Nm>(_M_parent->_M_bases)); |
8687 | _M_next<_Nm - 1>(); |
8688 | } |
8689 | } |
8690 | |
8691 | template<size_t _Nm = sizeof...(_Vs)> |
8692 | constexpr void |
8693 | _M_prev() |
8694 | { |
8695 | auto& __it = std::get<_Nm>(_M_current); |
8696 | if constexpr (_Nm > 0) |
8697 | if (__it == ranges::begin(std::get<_Nm>(_M_parent->_M_bases))) |
8698 | { |
8699 | __it = __detail::__cartesian_common_arg_end(std::get<_Nm>(_M_parent->_M_bases)); |
8700 | _M_prev<_Nm - 1>(); |
8701 | } |
8702 | --__it; |
8703 | } |
8704 | |
8705 | template<size_t _Nm = sizeof...(_Vs)> |
8706 | constexpr void |
8707 | _M_advance(difference_type __x) |
8708 | requires __detail::__cartesian_product_is_random_access<_Const, _First, _Vs...> |
8709 | { |
8710 | if (__x == 1) |
8711 | _M_next<_Nm>(); |
8712 | else if (__x == -1) |
8713 | _M_prev<_Nm>(); |
8714 | else if (__x != 0) |
8715 | { |
8716 | // Constant time iterator advancement. |
8717 | auto& __r = std::get<_Nm>(_M_parent->_M_bases); |
8718 | auto& __it = std::get<_Nm>(_M_current); |
8719 | if constexpr (_Nm == 0) |
8720 | { |
8721 | #ifdef _GLIBCXX_ASSERTIONS |
8722 | if constexpr (sized_range<__maybe_const_t<_Const, _First>>) |
8723 | { |
8724 | auto __size = ranges::ssize(__r); |
8725 | auto __begin = ranges::begin(__r); |
8726 | auto __offset = __it - __begin; |
8727 | __glibcxx_assert(__offset + __x >= 0 && __offset + __x <= __size); |
8728 | } |
8729 | #endif |
8730 | __it += __x; |
8731 | } |
8732 | else |
8733 | { |
8734 | auto __size = ranges::ssize(__r); |
8735 | auto __begin = ranges::begin(__r); |
8736 | auto __offset = __it - __begin; |
8737 | __offset += __x; |
8738 | __x = __offset / __size; |
8739 | __offset %= __size; |
8740 | if (__offset < 0) |
8741 | { |
8742 | __offset = __size + __offset; |
8743 | --__x; |
8744 | } |
8745 | __it = __begin + __offset; |
8746 | _M_advance<_Nm - 1>(__x); |
8747 | } |
8748 | } |
8749 | } |
8750 | |
8751 | template<typename _Tuple> |
8752 | constexpr difference_type |
8753 | _M_distance_from(const _Tuple& __t) const |
8754 | { |
8755 | return [&]<size_t... _Is>(index_sequence<_Is...>) { |
8756 | auto __sum = static_cast<difference_type>(0); |
8757 | #ifdef _GLIBCXX_ASSERTIONS |
8758 | if constexpr (integral<difference_type>) |
8759 | { |
8760 | bool __overflow |
8761 | = (__builtin_add_overflow(__sum, _M_scaled_distance<_Is>(__t), &__sum) |
8762 | || ...); |
8763 | __glibcxx_assert(!__overflow); |
8764 | } |
8765 | else |
8766 | #endif |
8767 | __sum = (_M_scaled_distance<_Is>(__t) + ...); |
8768 | return __sum; |
8769 | }(make_index_sequence<1 + sizeof...(_Vs)>{}); |
8770 | } |
8771 | |
8772 | template<size_t _Nm, typename _Tuple> |
8773 | constexpr difference_type |
8774 | _M_scaled_distance(const _Tuple& __t) const |
8775 | { |
8776 | auto __dist = static_cast<difference_type>(std::get<_Nm>(_M_current) |
8777 | - std::get<_Nm>(__t)); |
8778 | #ifdef _GLIBCXX_ASSERTIONS |
8779 | if constexpr (integral<difference_type>) |
8780 | { |
8781 | bool __overflow = __builtin_mul_overflow(__dist, _M_scaled_size<_Nm+1>(), &__dist); |
8782 | __glibcxx_assert(!__overflow); |
8783 | } |
8784 | else |
8785 | #endif |
8786 | __dist *= _M_scaled_size<_Nm+1>(); |
8787 | return __dist; |
8788 | } |
8789 | |
8790 | template<size_t _Nm> |
8791 | constexpr difference_type |
8792 | _M_scaled_size() const |
8793 | { |
8794 | if constexpr (_Nm <= sizeof...(_Vs)) |
8795 | { |
8796 | auto __size = static_cast<difference_type>(ranges::size |
8797 | (std::get<_Nm>(_M_parent->_M_bases))); |
8798 | #ifdef _GLIBCXX_ASSERTIONS |
8799 | if constexpr (integral<difference_type>) |
8800 | { |
8801 | bool __overflow = __builtin_mul_overflow(__size, _M_scaled_size<_Nm+1>(), &__size); |
8802 | __glibcxx_assert(!__overflow); |
8803 | } |
8804 | else |
8805 | #endif |
8806 | __size *= _M_scaled_size<_Nm+1>(); |
8807 | return __size; |
8808 | } |
8809 | else |
8810 | return static_cast<difference_type>(1); |
8811 | } |
8812 | }; |
8813 | |
8814 | namespace views |
8815 | { |
8816 | namespace __detail |
8817 | { |
8818 | template<typename... _Ts> |
8819 | concept __can_cartesian_product_view |
8820 | = requires { cartesian_product_view<all_t<_Ts>...>(std::declval<_Ts>()...); }; |
8821 | } |
8822 | |
8823 | struct _CartesianProduct |
8824 | { |
8825 | template<typename... _Ts> |
8826 | requires (sizeof...(_Ts) == 0 || __detail::__can_cartesian_product_view<_Ts...>) |
8827 | constexpr auto |
8828 | operator() [[nodiscard]] (_Ts&&... __ts) const |
8829 | { |
8830 | if constexpr (sizeof...(_Ts) == 0) |
8831 | return views::single(tuple{}); |
8832 | else |
8833 | return cartesian_product_view<all_t<_Ts>...>(std::forward<_Ts>(__ts)...); |
8834 | } |
8835 | }; |
8836 | |
8837 | inline constexpr _CartesianProduct cartesian_product; |
8838 | } |
8839 | #endif // __cpp_lib_ranges_cartesian_product |
8840 | |
8841 | #ifdef __cpp_lib_ranges_as_rvalue // C++ >= 23 |
8842 | template<input_range _Vp> |
8843 | requires view<_Vp> |
8844 | class as_rvalue_view : public view_interface<as_rvalue_view<_Vp>> |
8845 | { |
8846 | _Vp _M_base = _Vp(); |
8847 | |
8848 | public: |
8849 | as_rvalue_view() requires default_initializable<_Vp> = default; |
8850 | |
8851 | constexpr explicit |
8852 | as_rvalue_view(_Vp __base) |
8853 | : _M_base(std::move(__base)) |
8854 | { } |
8855 | |
8856 | constexpr _Vp |
8857 | base() const& requires copy_constructible<_Vp> |
8858 | { return _M_base; } |
8859 | |
8860 | constexpr _Vp |
8861 | base() && |
8862 | { return std::move(_M_base); } |
8863 | |
8864 | constexpr auto |
8865 | begin() requires (!__detail::__simple_view<_Vp>) |
8866 | { return move_iterator(ranges::begin(_M_base)); } |
8867 | |
8868 | constexpr auto |
8869 | begin() const requires range<const _Vp> |
8870 | { return move_iterator(ranges::begin(_M_base)); } |
8871 | |
8872 | constexpr auto |
8873 | end() requires (!__detail::__simple_view<_Vp>) |
8874 | { |
8875 | if constexpr (common_range<_Vp>) |
8876 | return move_iterator(ranges::end(_M_base)); |
8877 | else |
8878 | return move_sentinel(ranges::end(_M_base)); |
8879 | } |
8880 | |
8881 | constexpr auto |
8882 | end() const requires range<const _Vp> |
8883 | { |
8884 | if constexpr (common_range<const _Vp>) |
8885 | return move_iterator(ranges::end(_M_base)); |
8886 | else |
8887 | return move_sentinel(ranges::end(_M_base)); |
8888 | } |
8889 | |
8890 | constexpr auto |
8891 | size() requires sized_range<_Vp> |
8892 | { return ranges::size(_M_base); } |
8893 | |
8894 | constexpr auto |
8895 | size() const requires sized_range<const _Vp> |
8896 | { return ranges::size(_M_base); } |
8897 | }; |
8898 | |
8899 | template<typename _Range> |
8900 | as_rvalue_view(_Range&&) -> as_rvalue_view<views::all_t<_Range>>; |
8901 | |
8902 | template<typename _Tp> |
8903 | inline constexpr bool enable_borrowed_range<as_rvalue_view<_Tp>> |
8904 | = enable_borrowed_range<_Tp>; |
8905 | |
8906 | namespace views |
8907 | { |
8908 | namespace __detail |
8909 | { |
8910 | template<typename _Tp> |
8911 | concept __can_as_rvalue_view = requires { as_rvalue_view(std::declval<_Tp>()); }; |
8912 | } |
8913 | |
8914 | struct _AsRvalue : __adaptor::_RangeAdaptorClosure<_AsRvalue> |
8915 | { |
8916 | template<viewable_range _Range> |
8917 | requires __detail::__can_as_rvalue_view<_Range> |
8918 | constexpr auto |
8919 | operator() [[nodiscard]] (_Range&& __r) const |
8920 | { |
8921 | if constexpr (same_as<range_rvalue_reference_t<_Range>, |
8922 | range_reference_t<_Range>>) |
8923 | return views::all(std::forward<_Range>(__r)); |
8924 | else |
8925 | return as_rvalue_view(std::forward<_Range>(__r)); |
8926 | } |
8927 | }; |
8928 | |
8929 | inline constexpr _AsRvalue as_rvalue; |
8930 | } |
8931 | #endif // __cpp_lib_as_rvalue |
8932 | |
8933 | #ifdef __cpp_lib_ranges_enumerate // C++ >= 23 |
8934 | namespace __detail |
8935 | { |
8936 | template<typename _Range> |
8937 | concept __range_with_movable_reference = input_range<_Range> |
8938 | && move_constructible<range_reference_t<_Range>> |
8939 | && move_constructible<range_rvalue_reference_t<_Range>>; |
8940 | } |
8941 | |
8942 | template<view _Vp> |
8943 | requires __detail::__range_with_movable_reference<_Vp> |
8944 | class enumerate_view : public view_interface<enumerate_view<_Vp>> |
8945 | { |
8946 | _Vp _M_base = _Vp(); |
8947 | |
8948 | template<bool _Const> class _Iterator; |
8949 | template<bool _Const> class _Sentinel; |
8950 | |
8951 | public: |
8952 | enumerate_view() requires default_initializable<_Vp> = default; |
8953 | |
8954 | constexpr explicit |
8955 | enumerate_view(_Vp __base) |
8956 | : _M_base(std::move(__base)) |
8957 | { } |
8958 | |
8959 | constexpr auto |
8960 | begin() requires (!__detail::__simple_view<_Vp>) |
8961 | { return _Iterator<false>(ranges::begin(_M_base), 0); } |
8962 | |
8963 | constexpr auto |
8964 | begin() const requires __detail::__range_with_movable_reference<const _Vp> |
8965 | { return _Iterator<true>(ranges::begin(_M_base), 0); } |
8966 | |
8967 | constexpr auto |
8968 | end() requires (!__detail::__simple_view<_Vp>) |
8969 | { |
8970 | if constexpr (common_range<_Vp> && sized_range<_Vp>) |
8971 | return _Iterator<false>(ranges::end(_M_base), ranges::distance(_M_base)); |
8972 | else |
8973 | return _Sentinel<false>(ranges::end(_M_base)); |
8974 | } |
8975 | |
8976 | constexpr auto |
8977 | end() const requires __detail::__range_with_movable_reference<const _Vp> |
8978 | { |
8979 | if constexpr (common_range<const _Vp> && sized_range<const _Vp>) |
8980 | return _Iterator<true>(ranges::end(_M_base), ranges::distance(_M_base)); |
8981 | else |
8982 | return _Sentinel<true>(ranges::end(_M_base)); |
8983 | } |
8984 | |
8985 | constexpr auto |
8986 | size() requires sized_range<_Vp> |
8987 | { return ranges::size(_M_base); } |
8988 | |
8989 | constexpr auto |
8990 | size() const requires sized_range<const _Vp> |
8991 | { return ranges::size(_M_base); } |
8992 | |
8993 | constexpr _Vp |
8994 | base() const & requires copy_constructible<_Vp> |
8995 | { return _M_base; } |
8996 | |
8997 | constexpr _Vp |
8998 | base() && |
8999 | { return std::move(_M_base); } |
9000 | }; |
9001 | |
9002 | template<typename _Range> |
9003 | enumerate_view(_Range&&) -> enumerate_view<views::all_t<_Range>>; |
9004 | |
9005 | template<typename _Tp> |
9006 | inline constexpr bool enable_borrowed_range<enumerate_view<_Tp>> |
9007 | = enable_borrowed_range<_Tp>; |
9008 | |
9009 | template<view _Vp> |
9010 | requires __detail::__range_with_movable_reference<_Vp> |
9011 | template<bool _Const> |
9012 | class enumerate_view<_Vp>::_Iterator |
9013 | { |
9014 | using _Base = __maybe_const_t<_Const, _Vp>; |
9015 | |
9016 | static auto |
9017 | _S_iter_concept() |
9018 | { |
9019 | if constexpr (random_access_range<_Base>) |
9020 | return random_access_iterator_tag{}; |
9021 | else if constexpr (bidirectional_range<_Base>) |
9022 | return bidirectional_iterator_tag{}; |
9023 | else if constexpr (forward_range<_Base>) |
9024 | return forward_iterator_tag{}; |
9025 | else |
9026 | return input_iterator_tag{}; |
9027 | } |
9028 | |
9029 | friend enumerate_view; |
9030 | |
9031 | public: |
9032 | using iterator_category = input_iterator_tag; |
9033 | using iterator_concept = decltype(_S_iter_concept()); |
9034 | using difference_type = range_difference_t<_Base>; |
9035 | using value_type = tuple<difference_type, range_value_t<_Base>>; |
9036 | |
9037 | private: |
9038 | using __reference_type = tuple<difference_type, range_reference_t<_Base>>; |
9039 | |
9040 | iterator_t<_Base> _M_current = iterator_t<_Base>(); |
9041 | difference_type _M_pos = 0; |
9042 | |
9043 | constexpr explicit |
9044 | _Iterator(iterator_t<_Base> __current, difference_type __pos) |
9045 | : _M_current(std::move(__current)), _M_pos(__pos) |
9046 | { } |
9047 | |
9048 | public: |
9049 | _Iterator() requires default_initializable<iterator_t<_Base>> = default; |
9050 | |
9051 | constexpr |
9052 | _Iterator(_Iterator<!_Const> __i) |
9053 | requires _Const && convertible_to<iterator_t<_Vp>, iterator_t<_Base>> |
9054 | : _M_current(std::move(__i._M_current)), _M_pos(__i._M_pos) |
9055 | { } |
9056 | |
9057 | constexpr const iterator_t<_Base> & |
9058 | base() const & noexcept |
9059 | { return _M_current; } |
9060 | |
9061 | constexpr iterator_t<_Base> |
9062 | base() && |
9063 | { return std::move(_M_current); } |
9064 | |
9065 | constexpr difference_type |
9066 | index() const noexcept |
9067 | { return _M_pos; } |
9068 | |
9069 | constexpr auto |
9070 | operator*() const |
9071 | { return __reference_type(_M_pos, *_M_current); } |
9072 | |
9073 | constexpr _Iterator& |
9074 | operator++() |
9075 | { |
9076 | ++_M_current; |
9077 | ++_M_pos; |
9078 | return *this; |
9079 | } |
9080 | |
9081 | constexpr void |
9082 | operator++(int) |
9083 | { ++*this; } |
9084 | |
9085 | constexpr _Iterator |
9086 | operator++(int) requires forward_range<_Base> |
9087 | { |
9088 | auto __tmp = *this; |
9089 | ++*this; |
9090 | return __tmp; |
9091 | } |
9092 | |
9093 | constexpr _Iterator& |
9094 | operator--() requires bidirectional_range<_Base> |
9095 | { |
9096 | --_M_current; |
9097 | --_M_pos; |
9098 | return *this; |
9099 | } |
9100 | |
9101 | constexpr _Iterator |
9102 | operator--(int) requires bidirectional_range<_Base> |
9103 | { |
9104 | auto __tmp = *this; |
9105 | --*this; |
9106 | return __tmp; |
9107 | } |
9108 | |
9109 | constexpr _Iterator& |
9110 | operator+=(difference_type __n) requires random_access_range<_Base> |
9111 | { |
9112 | _M_current += __n; |
9113 | _M_pos += __n; |
9114 | return *this; |
9115 | } |
9116 | |
9117 | constexpr _Iterator& |
9118 | operator-=(difference_type __n) requires random_access_range<_Base> |
9119 | { |
9120 | _M_current -= __n; |
9121 | _M_pos -= __n; |
9122 | return *this; |
9123 | } |
9124 | |
9125 | constexpr auto |
9126 | operator[](difference_type __n) const requires random_access_range<_Base> |
9127 | { return __reference_type(_M_pos + __n, _M_current[__n]); } |
9128 | |
9129 | friend constexpr bool |
9130 | operator==(const _Iterator& __x, const _Iterator& __y) noexcept |
9131 | { return __x._M_pos == __y._M_pos; } |
9132 | |
9133 | friend constexpr strong_ordering |
9134 | operator<=>(const _Iterator& __x, const _Iterator& __y) noexcept |
9135 | { return __x._M_pos <=> __y._M_pos; } |
9136 | |
9137 | friend constexpr _Iterator |
9138 | operator+(const _Iterator& __x, difference_type __y) |
9139 | requires random_access_range<_Base> |
9140 | { return (auto(__x) += __y); } |
9141 | |
9142 | friend constexpr _Iterator |
9143 | operator+(difference_type __x, const _Iterator& __y) |
9144 | requires random_access_range<_Base> |
9145 | { return auto(__y) += __x; } |
9146 | |
9147 | friend constexpr _Iterator |
9148 | operator-(const _Iterator& __x, difference_type __y) |
9149 | requires random_access_range<_Base> |
9150 | { return auto(__x) -= __y; } |
9151 | |
9152 | friend constexpr difference_type |
9153 | operator-(const _Iterator& __x, const _Iterator& __y) |
9154 | { return __x._M_pos - __y._M_pos; } |
9155 | |
9156 | friend constexpr auto |
9157 | iter_move(const _Iterator& __i) |
9158 | noexcept(noexcept(ranges::iter_move(__i._M_current)) |
9159 | && is_nothrow_move_constructible_v<range_rvalue_reference_t<_Base>>) |
9160 | { |
9161 | return tuple<difference_type, range_rvalue_reference_t<_Base>> |
9162 | (__i._M_pos, ranges::iter_move(__i._M_current)); |
9163 | } |
9164 | }; |
9165 | |
9166 | template<view _Vp> |
9167 | requires __detail::__range_with_movable_reference<_Vp> |
9168 | template<bool _Const> |
9169 | class enumerate_view<_Vp>::_Sentinel |
9170 | { |
9171 | using _Base = __maybe_const_t<_Const, _Vp>; |
9172 | |
9173 | sentinel_t<_Base> _M_end = sentinel_t<_Base>(); |
9174 | |
9175 | constexpr explicit |
9176 | _Sentinel(sentinel_t<_Base> __end) |
9177 | : _M_end(std::move(__end)) |
9178 | { } |
9179 | |
9180 | friend enumerate_view; |
9181 | |
9182 | public: |
9183 | _Sentinel() = default; |
9184 | |
9185 | constexpr |
9186 | _Sentinel(_Sentinel<!_Const> __other) |
9187 | requires _Const && convertible_to<sentinel_t<_Vp>, sentinel_t<_Base>> |
9188 | : _M_end(std::move(__other._M_end)) |
9189 | { } |
9190 | |
9191 | constexpr sentinel_t<_Base> |
9192 | base() const |
9193 | { return _M_end; } |
9194 | |
9195 | template<bool _OtherConst> |
9196 | requires sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const_t<_OtherConst, _Vp>>> |
9197 | friend constexpr bool |
9198 | operator==(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
9199 | { return __x._M_current == __y._M_end; } |
9200 | |
9201 | template<bool _OtherConst> |
9202 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const_t<_OtherConst, _Vp>>> |
9203 | friend constexpr range_difference_t<__maybe_const_t<_OtherConst, _Vp>> |
9204 | operator-(const _Iterator<_OtherConst>& __x, const _Sentinel& __y) |
9205 | { return __x._M_current - __y._M_end; } |
9206 | |
9207 | template<bool _OtherConst> |
9208 | requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<__maybe_const_t<_OtherConst, _Vp>>> |
9209 | friend constexpr range_difference_t<__maybe_const_t<_OtherConst, _Vp>> |
9210 | operator-(const _Sentinel& __x, const _Iterator<_OtherConst>& __y) |
9211 | { return __x._M_end - __y._M_current; } |
9212 | }; |
9213 | |
9214 | namespace views |
9215 | { |
9216 | namespace __detail |
9217 | { |
9218 | template<typename _Tp> |
9219 | concept __can_enumerate_view |
9220 | = requires { enumerate_view<all_t<_Tp>>(std::declval<_Tp>()); }; |
9221 | } |
9222 | |
9223 | struct _Enumerate : __adaptor::_RangeAdaptorClosure<_Enumerate> |
9224 | { |
9225 | template<viewable_range _Range> |
9226 | requires __detail::__can_enumerate_view<_Range> |
9227 | constexpr auto |
9228 | operator() [[nodiscard]] (_Range&& __r) const |
9229 | { return enumerate_view<all_t<_Range>>(std::forward<_Range>(__r)); } |
9230 | }; |
9231 | |
9232 | inline constexpr _Enumerate enumerate; |
9233 | } |
9234 | #endif // __cpp_lib_ranges_enumerate |
9235 | |
9236 | #ifdef __cpp_lib_ranges_as_const // C++ >= 23 |
9237 | template<view _Vp> |
9238 | requires input_range<_Vp> |
9239 | class as_const_view : public view_interface<as_const_view<_Vp>> |
9240 | { |
9241 | _Vp _M_base = _Vp(); |
9242 | |
9243 | public: |
9244 | as_const_view() requires default_initializable<_Vp> = default; |
9245 | |
9246 | constexpr explicit |
9247 | as_const_view(_Vp __base) |
9248 | noexcept(is_nothrow_move_constructible_v<_Vp>) |
9249 | : _M_base(std::move(__base)) |
9250 | { } |
9251 | |
9252 | constexpr _Vp |
9253 | base() const & |
9254 | noexcept(is_nothrow_copy_constructible_v<_Vp>) |
9255 | requires copy_constructible<_Vp> |
9256 | { return _M_base; } |
9257 | |
9258 | constexpr _Vp |
9259 | base() && |
9260 | noexcept(is_nothrow_move_constructible_v<_Vp>) |
9261 | { return std::move(_M_base); } |
9262 | |
9263 | constexpr auto |
9264 | begin() requires (!__detail::__simple_view<_Vp>) |
9265 | { return ranges::cbegin(_M_base); } |
9266 | |
9267 | constexpr auto |
9268 | begin() const requires range<const _Vp> |
9269 | { return ranges::cbegin(_M_base); } |
9270 | |
9271 | constexpr auto |
9272 | end() requires (!__detail::__simple_view<_Vp>) |
9273 | { return ranges::cend(_M_base); } |
9274 | |
9275 | constexpr auto |
9276 | end() const requires range<const _Vp> |
9277 | { return ranges::cend(_M_base); } |
9278 | |
9279 | constexpr auto |
9280 | size() requires sized_range<_Vp> |
9281 | { return ranges::size(_M_base); } |
9282 | |
9283 | constexpr auto |
9284 | size() const requires sized_range<const _Vp> |
9285 | { return ranges::size(_M_base); } |
9286 | }; |
9287 | |
9288 | template<typename _Range> |
9289 | as_const_view(_Range&&) -> as_const_view<views::all_t<_Range>>; |
9290 | |
9291 | template<typename _Tp> |
9292 | inline constexpr bool enable_borrowed_range<as_const_view<_Tp>> |
9293 | = enable_borrowed_range<_Tp>; |
9294 | |
9295 | namespace views |
9296 | { |
9297 | namespace __detail |
9298 | { |
9299 | template<typename _Tp> |
9300 | inline constexpr bool __is_ref_view = false; |
9301 | |
9302 | template<typename _Range> |
9303 | inline constexpr bool __is_ref_view<ref_view<_Range>> = true; |
9304 | |
9305 | template<typename _Range> |
9306 | concept __can_as_const_view = requires { as_const_view(std::declval<_Range>()); }; |
9307 | } |
9308 | |
9309 | struct _AsConst : __adaptor::_RangeAdaptorClosure<_AsConst> |
9310 | { |
9311 | template<viewable_range _Range> |
9312 | constexpr auto |
9313 | operator()(_Range&& __r) const |
9314 | noexcept(noexcept(as_const_view(std::declval<_Range>()))) |
9315 | requires __detail::__can_as_const_view<_Range> |
9316 | { |
9317 | using _Tp = remove_cvref_t<_Range>; |
9318 | using element_type = remove_reference_t<range_reference_t<_Range>>; |
9319 | if constexpr (constant_range<views::all_t<_Range>>) |
9320 | return views::all(std::forward<_Range>(__r)); |
9321 | else if constexpr (__detail::__is_empty_view<_Tp>) |
9322 | return views::empty<const element_type>; |
9323 | else if constexpr (std::__detail::__is_span<_Tp>) |
9324 | return span<const element_type, _Tp::extent>(std::forward<_Range>(__r)); |
9325 | else if constexpr (__detail::__is_ref_view<_Tp> |
9326 | && constant_range<const element_type>) |
9327 | return ref_view(static_cast<const element_type&> |
9328 | (std::forward<_Range>(__r).base())); |
9329 | else if constexpr (is_lvalue_reference_v<_Range> |
9330 | && constant_range<const _Tp> |
9331 | && !view<_Tp>) |
9332 | return ref_view(static_cast<const _Tp&>(__r)); |
9333 | else |
9334 | return as_const_view(std::forward<_Range>(__r)); |
9335 | } |
9336 | }; |
9337 | |
9338 | inline constexpr _AsConst as_const; |
9339 | } |
9340 | #endif // __cpp_lib_as_const |
9341 | } // namespace ranges |
9342 | |
9343 | namespace views = ranges::views; |
9344 | |
9345 | #if __cpp_lib_ranges_to_container // C++ >= 23 |
9346 | namespace ranges |
9347 | { |
9348 | /// @cond undocumented |
9349 | namespace __detail |
9350 | { |
9351 | template<typename _Container> |
9352 | constexpr bool __reservable_container |
9353 | = sized_range<_Container> |
9354 | && requires(_Container& __c, range_size_t<_Container> __n) { |
9355 | __c.reserve(__n); |
9356 | { __c.capacity() } -> same_as<decltype(__n)>; |
9357 | { __c.max_size() } -> same_as<decltype(__n)>; |
9358 | }; |
9359 | |
9360 | template<typename _Cont, typename _Range> |
9361 | constexpr bool __toable = requires { |
9362 | requires (!input_range<_Cont> |
9363 | || convertible_to<range_reference_t<_Range>, |
9364 | range_value_t<_Cont>>); |
9365 | }; |
9366 | } // namespace __detail |
9367 | /// @endcond |
9368 | |
9369 | /// Convert a range to a container. |
9370 | /** |
9371 | * @tparam _Cont A container type. |
9372 | * @param __r A range that models the `input_range` concept. |
9373 | * @param __args... Arguments to pass to the container constructor. |
9374 | * @since C++23 |
9375 | * |
9376 | * This function converts a range to the `_Cont` type. |
9377 | * |
9378 | * For example, `std::ranges::to<std::vector<int>>(some_view)` |
9379 | * will convert the view to `std::vector<int>`. |
9380 | * |
9381 | * Additional constructor arguments for the container can be supplied after |
9382 | * the input range argument, e.g. |
9383 | * `std::ranges::to<std::vector<int, Alloc<int>>>(a_range, an_allocator)`. |
9384 | */ |
9385 | template<typename _Cont, input_range _Rg, typename... _Args> |
9386 | requires (!view<_Cont>) |
9387 | constexpr _Cont |
9388 | to [[nodiscard]] (_Rg&& __r, _Args&&... __args) |
9389 | { |
9390 | static_assert(!is_const_v<_Cont> && !is_volatile_v<_Cont>); |
9391 | static_assert(is_class_v<_Cont>); |
9392 | |
9393 | if constexpr (__detail::__toable<_Cont, _Rg>) |
9394 | { |
9395 | if constexpr (constructible_from<_Cont, _Rg, _Args...>) |
9396 | return _Cont(std::forward<_Rg>(__r), |
9397 | std::forward<_Args>(__args)...); |
9398 | else if constexpr (constructible_from<_Cont, from_range_t, _Rg, _Args...>) |
9399 | return _Cont(from_range, std::forward<_Rg>(__r), |
9400 | std::forward<_Args>(__args)...); |
9401 | else if constexpr (requires { requires common_range<_Rg>; |
9402 | typename __iter_category_t<iterator_t<_Rg>>; |
9403 | requires derived_from<__iter_category_t<iterator_t<_Rg>>, |
9404 | input_iterator_tag>; |
9405 | requires constructible_from<_Cont, iterator_t<_Rg>, |
9406 | sentinel_t<_Rg>, _Args...>; |
9407 | }) |
9408 | return _Cont(ranges::begin(__r), ranges::end(__r), |
9409 | std::forward<_Args>(__args)...); |
9410 | else |
9411 | { |
9412 | static_assert(constructible_from<_Cont, _Args...>); |
9413 | _Cont __c(std::forward<_Args>(__args)...); |
9414 | if constexpr (sized_range<_Rg> |
9415 | && __detail::__reservable_container<_Cont>) |
9416 | __c.reserve(static_cast<range_size_t<_Cont>>(ranges::size(__r))); |
9417 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
9418 | // 4016. container-insertable checks do not match what |
9419 | // container-inserter does |
9420 | auto __it = ranges::begin(__r); |
9421 | const auto __sent = ranges::end(__r); |
9422 | while (__it != __sent) |
9423 | { |
9424 | if constexpr (requires { __c.emplace_back(*__it); }) |
9425 | __c.emplace_back(*__it); |
9426 | else if constexpr (requires { __c.push_back(*__it); }) |
9427 | __c.push_back(*__it); |
9428 | else if constexpr (requires { __c.emplace(__c.end(), *__it); }) |
9429 | __c.emplace(__c.end(), *__it); |
9430 | else |
9431 | __c.insert(__c.end(), *__it); |
9432 | ++__it; |
9433 | } |
9434 | return __c; |
9435 | } |
9436 | } |
9437 | else |
9438 | { |
9439 | static_assert(input_range<range_reference_t<_Rg>>); |
9440 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
9441 | // 3984. ranges::to's recursion branch may be ill-formed |
9442 | return ranges::to<_Cont>(ref_view(__r) | views::transform( |
9443 | []<typename _Elt>(_Elt&& __elem) { |
9444 | using _ValT = range_value_t<_Cont>; |
9445 | return ranges::to<_ValT>(std::forward<_Elt>(__elem)); |
9446 | }), std::forward<_Args>(__args)...); |
9447 | } |
9448 | } |
9449 | |
9450 | /// @cond undocumented |
9451 | namespace __detail |
9452 | { |
9453 | template<typename _Rg> |
9454 | struct _InputIter |
9455 | { |
9456 | using iterator_category = input_iterator_tag; |
9457 | using value_type = range_value_t<_Rg>; |
9458 | using difference_type = ptrdiff_t; |
9459 | using pointer = add_pointer_t<range_reference_t<_Rg>>; |
9460 | using reference = range_reference_t<_Rg>; |
9461 | reference operator*() const; |
9462 | pointer operator->() const; |
9463 | _InputIter& operator++(); |
9464 | _InputIter operator++(int); |
9465 | bool operator==(const _InputIter&) const; |
9466 | }; |
9467 | |
9468 | template<template<typename...> typename _Cont, input_range _Rg, |
9469 | typename... _Args> |
9470 | using _DeduceExpr1 |
9471 | = decltype(_Cont(std::declval<_Rg>(), std::declval<_Args>()...)); |
9472 | |
9473 | template<template<typename...> typename _Cont, input_range _Rg, |
9474 | typename... _Args> |
9475 | using _DeduceExpr2 |
9476 | = decltype(_Cont(from_range, std::declval<_Rg>(), |
9477 | std::declval<_Args>()...)); |
9478 | |
9479 | template<template<typename...> typename _Cont, input_range _Rg, |
9480 | typename... _Args> |
9481 | using _DeduceExpr3 |
9482 | = decltype(_Cont(std::declval<_InputIter<_Rg>>(), |
9483 | std::declval<_InputIter<_Rg>>(), |
9484 | std::declval<_Args>()...)); |
9485 | |
9486 | } // namespace __detail |
9487 | /// @endcond |
9488 | |
9489 | template<template<typename...> typename _Cont, input_range _Rg, |
9490 | typename... _Args> |
9491 | constexpr auto |
9492 | to [[nodiscard]] (_Rg&& __r, _Args&&... __args) |
9493 | { |
9494 | using __detail::_DeduceExpr1; |
9495 | using __detail::_DeduceExpr2; |
9496 | using __detail::_DeduceExpr3; |
9497 | if constexpr (requires { typename _DeduceExpr1<_Cont, _Rg, _Args...>; }) |
9498 | return ranges::to<_DeduceExpr1<_Cont, _Rg, _Args...>>( |
9499 | std::forward<_Rg>(__r), std::forward<_Args>(__args)...); |
9500 | else if constexpr (requires { typename _DeduceExpr2<_Cont, _Rg, _Args...>; }) |
9501 | return ranges::to<_DeduceExpr2<_Cont, _Rg, _Args...>>( |
9502 | std::forward<_Rg>(__r), std::forward<_Args>(__args)...); |
9503 | else if constexpr (requires { typename _DeduceExpr3<_Cont, _Rg, _Args...>; }) |
9504 | return ranges::to<_DeduceExpr3<_Cont, _Rg, _Args...>>( |
9505 | std::forward<_Rg>(__r), std::forward<_Args>(__args)...); |
9506 | else |
9507 | static_assert(false); // Cannot deduce container specialization. |
9508 | } |
9509 | |
9510 | /// @cond undocumented |
9511 | namespace __detail |
9512 | { |
9513 | template<typename _Cont> |
9514 | struct _To |
9515 | { |
9516 | template<typename _Range, typename... _Args> |
9517 | requires requires { ranges::to<_Cont>(std::declval<_Range>(), |
9518 | std::declval<_Args>()...); } |
9519 | constexpr auto |
9520 | operator()(_Range&& __r, _Args&&... __args) const |
9521 | { |
9522 | return ranges::to<_Cont>(std::forward<_Range>(__r), |
9523 | std::forward<_Args>(__args)...); |
9524 | } |
9525 | }; |
9526 | } // namespace __detail |
9527 | /// @endcond |
9528 | |
9529 | /// ranges::to adaptor for converting a range to a container type |
9530 | /** |
9531 | * @tparam _Cont A container type. |
9532 | * @param __args... Arguments to pass to the container constructor. |
9533 | * @since C++23 |
9534 | * |
9535 | * This range adaptor returns a range adaptor closure object that converts |
9536 | * a range to the `_Cont` type. |
9537 | * |
9538 | * For example, `some_view | std::ranges::to<std::vector<int>>()` |
9539 | * will convert the view to `std::vector<int>`. |
9540 | * |
9541 | * Additional constructor arguments for the container can be supplied, e.g. |
9542 | * `r | std::ranges::to<std::vector<int, Alloc<int>>>(an_allocator)`. |
9543 | */ |
9544 | template<typename _Cont, typename... _Args> |
9545 | requires (!view<_Cont>) |
9546 | constexpr auto |
9547 | to [[nodiscard]] (_Args&&... __args) |
9548 | { |
9549 | using __detail::_To; |
9550 | using views::__adaptor::_Partial; |
9551 | return _Partial<_To<_Cont>, decay_t<_Args>...>{0, std::forward<_Args>(__args)...}; |
9552 | } |
9553 | |
9554 | /// @cond undocumented |
9555 | namespace __detail |
9556 | { |
9557 | template<template<typename...> typename _Cont> |
9558 | struct _To2 |
9559 | { |
9560 | template<typename _Range, typename... _Args> |
9561 | requires requires { ranges::to<_Cont>(std::declval<_Range>(), |
9562 | std::declval<_Args>()...); } |
9563 | constexpr auto |
9564 | operator()(_Range&& __r, _Args&&... __args) const |
9565 | { |
9566 | return ranges::to<_Cont>(std::forward<_Range>(__r), |
9567 | std::forward<_Args>(__args)...); |
9568 | } |
9569 | }; |
9570 | } // namespace __detail |
9571 | /// @endcond |
9572 | |
9573 | /// ranges::to adaptor for converting a range to a deduced container type. |
9574 | /** |
9575 | * @tparam _Cont A container template. |
9576 | * @param __args... Arguments to pass to the container constructor. |
9577 | * @since C++23 |
9578 | * |
9579 | * This range adaptor returns a range adaptor closure object that converts |
9580 | * a range to a specialization of the `_Cont` class template. The specific |
9581 | * specialization of `_Cont` to be used is deduced automatically. |
9582 | * |
9583 | * For example, `some_view | std::ranges::to<std::vector>(Alloc<int>{})` |
9584 | * will convert the view to `std::vector<T, Alloc<T>>`, where `T` is the |
9585 | * view's value type, i.e. `std::ranges::range_value_t<decltype(some_view)>`. |
9586 | * |
9587 | * Additional constructor arguments for the container can be supplied, e.g. |
9588 | * `r | std::ranges::to<std::vector>(an_allocator)`. |
9589 | */ |
9590 | template<template<typename...> typename _Cont, typename... _Args> |
9591 | constexpr auto |
9592 | to [[nodiscard]] (_Args&&... __args) |
9593 | { |
9594 | using __detail::_To2; |
9595 | using views::__adaptor::_Partial; |
9596 | return _Partial<_To2<_Cont>, decay_t<_Args>...>{0, std::forward<_Args>(__args)...}; |
9597 | } |
9598 | |
9599 | } // namespace ranges |
9600 | #endif // __cpp_lib_ranges_to_container |
9601 | |
9602 | _GLIBCXX_END_NAMESPACE_VERSION |
9603 | } // namespace std |
9604 | #endif // library concepts |
9605 | #endif // C++2a |
9606 | #endif /* _GLIBCXX_RANGES */ |
9607 | |