1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_ARRAY
11#define _LIBCPP_ARRAY
12
13/*
14 array synopsis
15
16namespace std
17{
18template <class T, size_t N >
19struct array
20{
21 // types:
22 using value_type = T;
23 using pointer = T*;
24 using const_pointer = const T*;
25 using reference = T&;
26 using const_reference = const T&;
27 using size_type = size_t;
28 using difference_type = ptrdiff_t;
29 using iterator = implementation-defined;
30 using const_iterator = implementation-defined;
31 using reverse_iterator = std::reverse_iterator<iterator>;
32 using const_reverse_iterator = std::reverse_iterator<const_iterator>;
33
34 // No explicit construct/copy/destroy for aggregate type
35 void fill(const T& u); // constexpr in C++20
36 void swap(array& a) noexcept(is_nothrow_swappable_v<T>); // constexpr in C++20
37
38 // iterators:
39 iterator begin() noexcept; // constexpr in C++17
40 const_iterator begin() const noexcept; // constexpr in C++17
41 iterator end() noexcept; // constexpr in C++17
42 const_iterator end() const noexcept; // constexpr in C++17
43
44 reverse_iterator rbegin() noexcept; // constexpr in C++17
45 const_reverse_iterator rbegin() const noexcept; // constexpr in C++17
46 reverse_iterator rend() noexcept; // constexpr in C++17
47 const_reverse_iterator rend() const noexcept; // constexpr in C++17
48
49 const_iterator cbegin() const noexcept; // constexpr in C++17
50 const_iterator cend() const noexcept; // constexpr in C++17
51 const_reverse_iterator crbegin() const noexcept; // constexpr in C++17
52 const_reverse_iterator crend() const noexcept; // constexpr in C++17
53
54 // capacity:
55 constexpr size_type size() const noexcept;
56 constexpr size_type max_size() const noexcept;
57 constexpr bool empty() const noexcept;
58
59 // element access:
60 reference operator[](size_type n); // constexpr in C++17
61 const_reference operator[](size_type n) const; // constexpr in C++14
62 reference at(size_type n); // constexpr in C++17
63 const_reference at(size_type n) const; // constexpr in C++14
64
65 reference front(); // constexpr in C++17
66 const_reference front() const; // constexpr in C++14
67 reference back(); // constexpr in C++17
68 const_reference back() const; // constexpr in C++14
69
70 T* data() noexcept; // constexpr in C++17
71 const T* data() const noexcept; // constexpr in C++17
72};
73
74template <class T, class... U>
75 array(T, U...) -> array<T, 1 + sizeof...(U)>; // C++17
76
77template <class T, size_t N>
78 bool operator==(const array<T,N>& x, const array<T,N>& y); // constexpr in C++20
79template <class T, size_t N>
80 bool operator!=(const array<T,N>& x, const array<T,N>& y); // removed in C++20
81template <class T, size_t N>
82 bool operator<(const array<T,N>& x, const array<T,N>& y); // removed in C++20
83template <class T, size_t N>
84 bool operator>(const array<T,N>& x, const array<T,N>& y); // removed in C++20
85template <class T, size_t N>
86 bool operator<=(const array<T,N>& x, const array<T,N>& y); // removed in C++20
87template <class T, size_t N>
88 bool operator>=(const array<T,N>& x, const array<T,N>& y); // removed in C++20
89template<class T, size_t N>
90 constexpr synth-three-way-result<T>
91 operator<=>(const array<T, N>& x, const array<T, N>& y); // since C++20
92
93template <class T, size_t N >
94 void swap(array<T,N>& x, array<T,N>& y) noexcept(noexcept(x.swap(y))); // constexpr in C++20
95
96template <class T, size_t N>
97 constexpr array<remove_cv_t<T>, N> to_array(T (&a)[N]); // C++20
98template <class T, size_t N>
99 constexpr array<remove_cv_t<T>, N> to_array(T (&&a)[N]); // C++20
100
101template <class T> struct tuple_size;
102template <size_t I, class T> struct tuple_element;
103template <class T, size_t N> struct tuple_size<array<T, N>>;
104template <size_t I, class T, size_t N> struct tuple_element<I, array<T, N>>;
105template <size_t I, class T, size_t N> T& get(array<T, N>&) noexcept; // constexpr in C++14
106template <size_t I, class T, size_t N> const T& get(const array<T, N>&) noexcept; // constexpr in C++14
107template <size_t I, class T, size_t N> T&& get(array<T, N>&&) noexcept; // constexpr in C++14
108template <size_t I, class T, size_t N> const T&& get(const array<T, N>&&) noexcept; // constexpr in C++14
109
110} // std
111
112*/
113
114#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
115# include <__cxx03/array>
116#else
117# include <__algorithm/equal.h>
118# include <__algorithm/fill_n.h>
119# include <__algorithm/lexicographical_compare.h>
120# include <__algorithm/lexicographical_compare_three_way.h>
121# include <__algorithm/swap_ranges.h>
122# include <__assert>
123# include <__config>
124# include <__cstddef/ptrdiff_t.h>
125# include <__fwd/array.h>
126# include <__iterator/reverse_iterator.h>
127# include <__iterator/static_bounded_iter.h>
128# include <__iterator/wrap_iter.h>
129# include <__tuple/sfinae_helpers.h>
130# include <__type_traits/conditional.h>
131# include <__type_traits/conjunction.h>
132# include <__type_traits/enable_if.h>
133# include <__type_traits/is_array.h>
134# include <__type_traits/is_const.h>
135# include <__type_traits/is_constructible.h>
136# include <__type_traits/is_nothrow_constructible.h>
137# include <__type_traits/is_same.h>
138# include <__type_traits/is_swappable.h>
139# include <__type_traits/is_trivially_relocatable.h>
140# include <__type_traits/remove_cv.h>
141# include <__utility/empty.h>
142# include <__utility/integer_sequence.h>
143# include <__utility/move.h>
144# include <__utility/unreachable.h>
145# include <stdexcept>
146# include <version>
147
148// standard-mandated includes
149
150// [iterator.range]
151# include <__iterator/access.h>
152# include <__iterator/data.h>
153# include <__iterator/empty.h>
154# include <__iterator/reverse_access.h>
155# include <__iterator/size.h>
156
157// [array.syn]
158# include <compare>
159# include <initializer_list>
160
161// [tuple.helper]
162# include <__tuple/tuple_element.h>
163# include <__tuple/tuple_size.h>
164
165# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
166# pragma GCC system_header
167# endif
168
169_LIBCPP_PUSH_MACROS
170# include <__undef_macros>
171
172_LIBCPP_BEGIN_NAMESPACE_STD
173
174template <class _Tp, size_t _Size>
175struct array {
176 using __trivially_relocatable _LIBCPP_NODEBUG =
177 __conditional_t<__libcpp_is_trivially_relocatable<_Tp>::value, array, void>;
178
179 // types:
180 using __self _LIBCPP_NODEBUG = array;
181 using value_type = _Tp;
182 using reference = value_type&;
183 using const_reference = const value_type&;
184 using pointer = value_type*;
185 using const_pointer = const value_type*;
186# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
187 using iterator = __static_bounded_iter<pointer, _Size>;
188 using const_iterator = __static_bounded_iter<const_pointer, _Size>;
189# elif defined(_LIBCPP_ABI_USE_WRAP_ITER_IN_STD_ARRAY)
190 using iterator = __wrap_iter<pointer>;
191 using const_iterator = __wrap_iter<const_pointer>;
192# else
193 using iterator = pointer;
194 using const_iterator = const_pointer;
195# endif
196 using size_type = size_t;
197 using difference_type = ptrdiff_t;
198 using reverse_iterator = std::reverse_iterator<iterator>;
199 using const_reverse_iterator = std::reverse_iterator<const_iterator>;
200
201 _Tp __elems_[_Size];
202
203 // No explicit construct/copy/destroy for aggregate type
204 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type& __u) {
205 std::fill_n(data(), _Size, __u);
206 }
207
208 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array& __a) _NOEXCEPT_(__is_nothrow_swappable_v<_Tp>) {
209 std::swap_ranges(data(), data() + _Size, __a.data());
210 }
211
212 // iterators:
213 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT {
214# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
215 return std::__make_static_bounded_iter<_Size>(data(), data());
216# else
217 return iterator(data());
218# endif
219 }
220 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
221# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
222 return std::__make_static_bounded_iter<_Size>(data(), data());
223# else
224 return const_iterator(data());
225# endif
226 }
227 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT {
228# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
229 return std::__make_static_bounded_iter<_Size>(data() + _Size, data());
230# else
231 return iterator(data() + _Size);
232# endif
233 }
234 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
235# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
236 return std::__make_static_bounded_iter<_Size>(data() + _Size, data());
237# else
238 return const_iterator(data() + _Size);
239# endif
240 }
241
242 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
243 return reverse_iterator(end());
244 }
245 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
246 rbegin() const _NOEXCEPT {
247 return const_reverse_iterator(end());
248 }
249 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
250 return reverse_iterator(begin());
251 }
252 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
253 return const_reverse_iterator(begin());
254 }
255
256 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT {
257 return begin();
258 }
259 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT {
260 return end();
261 }
262 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
263 crbegin() const _NOEXCEPT {
264 return rbegin();
265 }
266 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT {
267 return rend();
268 }
269
270 // capacity:
271 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return _Size; }
272 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return _Size; }
273 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return _Size == 0; }
274
275 // element access:
276 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type __n) _NOEXCEPT {
277 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
278 return __elems_[__n];
279 }
280 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference
281 operator[](size_type __n) const _NOEXCEPT {
282 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
283 return __elems_[__n];
284 }
285
286 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type __n) {
287 if (__n >= _Size)
288 std::__throw_out_of_range(msg: "array::at");
289 return __elems_[__n];
290 }
291
292 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type __n) const {
293 if (__n >= _Size)
294 std::__throw_out_of_range(msg: "array::at");
295 return __elems_[__n];
296 }
297
298 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT {
299 return (*this)[0];
300 }
301 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT {
302 return (*this)[0];
303 }
304 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT {
305 return (*this)[_Size - 1];
306 }
307 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
308 return (*this)[_Size - 1];
309 }
310
311 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT {
312 return __elems_;
313 }
314 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT {
315 return __elems_;
316 }
317};
318
319template <class _Tp>
320struct array<_Tp, 0> {
321 // types:
322 using __self _LIBCPP_NODEBUG = array;
323 using value_type = _Tp;
324 using reference = value_type&;
325 using const_reference = const value_type&;
326 using pointer = value_type*;
327 using const_pointer = const value_type*;
328# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
329 using iterator = __static_bounded_iter<pointer, 0>;
330 using const_iterator = __static_bounded_iter<const_pointer, 0>;
331# elif defined(_LIBCPP_ABI_USE_WRAP_ITER_IN_STD_ARRAY)
332 using iterator = __wrap_iter<pointer>;
333 using const_iterator = __wrap_iter<const_pointer>;
334# else
335 using iterator = pointer;
336 using const_iterator = const_pointer;
337# endif
338 using size_type = size_t;
339 using difference_type = ptrdiff_t;
340 using reverse_iterator = std::reverse_iterator<iterator>;
341 using const_reverse_iterator = std::reverse_iterator<const_iterator>;
342
343 using _EmptyType _LIBCPP_NODEBUG = __conditional_t<is_const<_Tp>::value, const __empty, __empty>;
344
345 struct _ArrayInStructT {
346 _Tp __data_[1];
347 };
348 _ALIGNAS_TYPE(_ArrayInStructT) _EmptyType __elems_[sizeof(_ArrayInStructT)];
349
350 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return nullptr; }
351 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT {
352 return nullptr;
353 }
354
355 // No explicit construct/copy/destroy for aggregate type
356 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type&) {
357 static_assert(!is_const<_Tp>::value, "cannot fill zero-sized array of type 'const T'");
358 }
359
360 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array&) _NOEXCEPT {
361 static_assert(!is_const<_Tp>::value, "cannot swap zero-sized array of type 'const T'");
362 }
363
364 // iterators:
365 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT {
366# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
367 return std::__make_static_bounded_iter<0>(data(), data());
368# else
369 return iterator(data());
370# endif
371 }
372 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
373# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
374 return std::__make_static_bounded_iter<0>(data(), data());
375# else
376 return const_iterator(data());
377# endif
378 }
379 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT {
380# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
381 return std::__make_static_bounded_iter<0>(data(), data());
382# else
383 return iterator(data());
384# endif
385 }
386 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
387# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
388 return std::__make_static_bounded_iter<0>(data(), data());
389# else
390 return const_iterator(data());
391# endif
392 }
393
394 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
395 return reverse_iterator(end());
396 }
397 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
398 rbegin() const _NOEXCEPT {
399 return const_reverse_iterator(end());
400 }
401 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
402 return reverse_iterator(begin());
403 }
404 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
405 return const_reverse_iterator(begin());
406 }
407
408 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT {
409 return begin();
410 }
411 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT {
412 return end();
413 }
414 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
415 crbegin() const _NOEXCEPT {
416 return rbegin();
417 }
418 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT {
419 return rend();
420 }
421
422 // capacity:
423 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return 0; }
424 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return 0; }
425 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return true; }
426
427 // element access:
428 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type) _NOEXCEPT {
429 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
430 __libcpp_unreachable();
431 }
432
433 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference
434 operator[](size_type) const _NOEXCEPT {
435 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
436 __libcpp_unreachable();
437 }
438
439 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type) {
440 std::__throw_out_of_range(msg: "array<T, 0>::at");
441 __libcpp_unreachable();
442 }
443
444 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type) const {
445 std::__throw_out_of_range(msg: "array<T, 0>::at");
446 __libcpp_unreachable();
447 }
448
449 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT {
450 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
451 __libcpp_unreachable();
452 }
453
454 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT {
455 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
456 __libcpp_unreachable();
457 }
458
459 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT {
460 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
461 __libcpp_unreachable();
462 }
463
464 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
465 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
466 __libcpp_unreachable();
467 }
468};
469
470# if _LIBCPP_STD_VER >= 17
471template <class _Tp, class... _Args, class = enable_if_t<__all<_IsSame<_Tp, _Args>::value...>::value> >
472array(_Tp, _Args...) -> array<_Tp, 1 + sizeof...(_Args)>;
473# endif
474
475template <class _Tp, size_t _Size>
476inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
477operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
478 return std::equal(__x.begin(), __x.end(), __y.begin());
479}
480
481# if _LIBCPP_STD_VER <= 17
482
483template <class _Tp, size_t _Size>
484inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
485 return !(__x == __y);
486}
487
488template <class _Tp, size_t _Size>
489inline _LIBCPP_HIDE_FROM_ABI bool operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
490 return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
491}
492
493template <class _Tp, size_t _Size>
494inline _LIBCPP_HIDE_FROM_ABI bool operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
495 return __y < __x;
496}
497
498template <class _Tp, size_t _Size>
499inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
500 return !(__y < __x);
501}
502
503template <class _Tp, size_t _Size>
504inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
505 return !(__x < __y);
506}
507
508# else // _LIBCPP_STD_VER <= 17
509
510template <class _Tp, size_t _Size>
511_LIBCPP_HIDE_FROM_ABI constexpr __synth_three_way_result<_Tp>
512operator<=>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
513 return std::lexicographical_compare_three_way(__x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
514}
515
516# endif // _LIBCPP_STD_VER <= 17
517
518template <class _Tp, size_t _Size, __enable_if_t<_Size == 0 || __is_swappable_v<_Tp>, int> = 0>
519inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
520 _NOEXCEPT_(noexcept(__x.swap(__y))) {
521 __x.swap(__y);
522}
523
524template <class _Tp, size_t _Size>
525struct tuple_size<array<_Tp, _Size> > : public integral_constant<size_t, _Size> {};
526
527template <size_t _Ip, class _Tp, size_t _Size>
528struct tuple_element<_Ip, array<_Tp, _Size> > {
529 static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
530 using type _LIBCPP_NODEBUG = _Tp;
531};
532
533template <size_t _Ip, class _Tp, size_t _Size>
534[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&
535get(array<_Tp, _Size>& __a) _NOEXCEPT {
536 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
537 return __a.__elems_[_Ip];
538}
539
540template <size_t _Ip, class _Tp, size_t _Size>
541[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&
542get(const array<_Tp, _Size>& __a) _NOEXCEPT {
543 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
544 return __a.__elems_[_Ip];
545}
546
547template <size_t _Ip, class _Tp, size_t _Size>
548[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&&
549get(array<_Tp, _Size>&& __a) _NOEXCEPT {
550 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
551 return std::move(__a.__elems_[_Ip]);
552}
553
554template <size_t _Ip, class _Tp, size_t _Size>
555[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&&
556get(const array<_Tp, _Size>&& __a) _NOEXCEPT {
557 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
558 return std::move(__a.__elems_[_Ip]);
559}
560
561# if _LIBCPP_STD_VER >= 20
562
563template <typename _Tp, size_t _Size, size_t... _Index>
564_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
565__to_array_lvalue_impl(_Tp (&__arr)[_Size], index_sequence<_Index...>) {
566 return {{__arr[_Index]...}};
567}
568
569template <typename _Tp, size_t _Size, size_t... _Index>
570_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
571__to_array_rvalue_impl(_Tp (&&__arr)[_Size], index_sequence<_Index...>) {
572 return {{std::move(__arr[_Index])...}};
573}
574
575template <typename _Tp, size_t _Size>
576[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
577to_array(_Tp (&__arr)[_Size]) noexcept(is_nothrow_constructible_v<_Tp, _Tp&>) {
578 static_assert(!is_array_v<_Tp>, "[array.creation]/1: to_array does not accept multidimensional arrays.");
579 static_assert(is_constructible_v<_Tp, _Tp&>, "[array.creation]/1: to_array requires copy constructible elements.");
580 return std::__to_array_lvalue_impl(__arr, make_index_sequence<_Size>());
581}
582
583template <typename _Tp, size_t _Size>
584[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
585to_array(_Tp (&&__arr)[_Size]) noexcept(is_nothrow_move_constructible_v<_Tp>) {
586 static_assert(!is_array_v<_Tp>, "[array.creation]/4: to_array does not accept multidimensional arrays.");
587 static_assert(is_move_constructible_v<_Tp>, "[array.creation]/4: to_array requires move constructible elements.");
588 return std::__to_array_rvalue_impl(std::move(__arr), make_index_sequence<_Size>());
589}
590
591# endif // _LIBCPP_STD_VER >= 20
592
593_LIBCPP_END_NAMESPACE_STD
594
595_LIBCPP_POP_MACROS
596
597# if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
598# include <algorithm>
599# include <concepts>
600# include <cstdlib>
601# include <iterator>
602# include <new>
603# include <optional>
604# include <type_traits>
605# include <utility>
606# endif
607#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
608
609#endif // _LIBCPP_ARRAY
610