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