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