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_relocatable.h>
138# include <__type_traits/is_same.h>
139# include <__type_traits/is_swappable.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 = __conditional_t<__is_trivially_relocatable_v<_Tp>, array, void>;
177
178 // types:
179 using __self _LIBCPP_NODEBUG = array;
180 using value_type = _Tp;
181 using reference = value_type&;
182 using const_reference = const value_type&;
183 using pointer = value_type*;
184 using const_pointer = const value_type*;
185# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
186 using iterator = __static_bounded_iter<pointer, _Size>;
187 using const_iterator = __static_bounded_iter<const_pointer, _Size>;
188# elif defined(_LIBCPP_ABI_USE_WRAP_ITER_IN_STD_ARRAY)
189 using iterator = __wrap_iter<pointer>;
190 using const_iterator = __wrap_iter<const_pointer>;
191# else
192 using iterator = pointer;
193 using const_iterator = const_pointer;
194# endif
195 using size_type = size_t;
196 using difference_type = ptrdiff_t;
197 using reverse_iterator = std::reverse_iterator<iterator>;
198 using const_reverse_iterator = std::reverse_iterator<const_iterator>;
199
200 _Tp __elems_[_Size];
201
202 // No explicit construct/copy/destroy for aggregate type
203 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type& __u) {
204 std::fill_n(data(), _Size, __u);
205 }
206
207 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array& __a) _NOEXCEPT_(__is_nothrow_swappable_v<_Tp>) {
208 std::swap_ranges(data(), data() + _Size, __a.data());
209 }
210
211 // iterators:
212 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT {
213# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
214 return std::__make_static_bounded_iter<_Size>(data(), data());
215# else
216 return iterator(data());
217# endif
218 }
219 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
220# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
221 return std::__make_static_bounded_iter<_Size>(data(), data());
222# else
223 return const_iterator(data());
224# endif
225 }
226 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT {
227# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
228 return std::__make_static_bounded_iter<_Size>(data() + _Size, data());
229# else
230 return iterator(data() + _Size);
231# endif
232 }
233 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
234# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
235 return std::__make_static_bounded_iter<_Size>(data() + _Size, data());
236# else
237 return const_iterator(data() + _Size);
238# endif
239 }
240
241 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
242 return reverse_iterator(end());
243 }
244 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
245 rbegin() const _NOEXCEPT {
246 return const_reverse_iterator(end());
247 }
248 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
249 return reverse_iterator(begin());
250 }
251 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
252 return const_reverse_iterator(begin());
253 }
254
255 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT {
256 return begin();
257 }
258 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT {
259 return end();
260 }
261 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
262 crbegin() const _NOEXCEPT {
263 return rbegin();
264 }
265 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT {
266 return rend();
267 }
268
269 // capacity:
270 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return _Size; }
271 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return _Size; }
272 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return _Size == 0; }
273
274 // element access:
275 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type __n) _NOEXCEPT {
276 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
277 return __elems_[__n];
278 }
279 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference
280 operator[](size_type __n) const _NOEXCEPT {
281 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
282 return __elems_[__n];
283 }
284
285 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type __n) {
286 if (__n >= _Size)
287 std::__throw_out_of_range(msg: "array::at");
288 return __elems_[__n];
289 }
290
291 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type __n) const {
292 if (__n >= _Size)
293 std::__throw_out_of_range(msg: "array::at");
294 return __elems_[__n];
295 }
296
297 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT {
298 return (*this)[0];
299 }
300 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT {
301 return (*this)[0];
302 }
303 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT {
304 return (*this)[_Size - 1];
305 }
306 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
307 return (*this)[_Size - 1];
308 }
309
310 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT {
311 return __elems_;
312 }
313 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT {
314 return __elems_;
315 }
316};
317
318template <class _Tp>
319struct array<_Tp, 0> {
320 // types:
321 using __self _LIBCPP_NODEBUG = array;
322 using value_type = _Tp;
323 using reference = value_type&;
324 using const_reference = const value_type&;
325 using pointer = value_type*;
326 using const_pointer = const value_type*;
327# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
328 using iterator = __static_bounded_iter<pointer, 0>;
329 using const_iterator = __static_bounded_iter<const_pointer, 0>;
330# elif defined(_LIBCPP_ABI_USE_WRAP_ITER_IN_STD_ARRAY)
331 using iterator = __wrap_iter<pointer>;
332 using const_iterator = __wrap_iter<const_pointer>;
333# else
334 using iterator = pointer;
335 using const_iterator = const_pointer;
336# endif
337 using size_type = size_t;
338 using difference_type = ptrdiff_t;
339 using reverse_iterator = std::reverse_iterator<iterator>;
340 using const_reverse_iterator = std::reverse_iterator<const_iterator>;
341
342 using _EmptyType _LIBCPP_NODEBUG = __conditional_t<is_const<_Tp>::value, const __empty, __empty>;
343
344 struct _ArrayInStructT {
345 _Tp __data_[1];
346 };
347 _ALIGNAS_TYPE(_ArrayInStructT) _EmptyType __elems_[sizeof(_ArrayInStructT)];
348
349 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return nullptr; }
350 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT {
351 return nullptr;
352 }
353
354 // No explicit construct/copy/destroy for aggregate type
355 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type&) {
356 static_assert(!is_const<_Tp>::value, "cannot fill zero-sized array of type 'const T'");
357 }
358
359 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array&) _NOEXCEPT {
360 static_assert(!is_const<_Tp>::value, "cannot swap zero-sized array of type 'const T'");
361 }
362
363 // iterators:
364 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT {
365# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
366 return std::__make_static_bounded_iter<0>(data(), data());
367# else
368 return iterator(data());
369# endif
370 }
371 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
372# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
373 return std::__make_static_bounded_iter<0>(data(), data());
374# else
375 return const_iterator(data());
376# endif
377 }
378 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT {
379# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
380 return std::__make_static_bounded_iter<0>(data(), data());
381# else
382 return iterator(data());
383# endif
384 }
385 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
386# if defined(_LIBCPP_ABI_BOUNDED_ITERATORS_IN_STD_ARRAY)
387 return std::__make_static_bounded_iter<0>(data(), data());
388# else
389 return const_iterator(data());
390# endif
391 }
392
393 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
394 return reverse_iterator(end());
395 }
396 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
397 rbegin() const _NOEXCEPT {
398 return const_reverse_iterator(end());
399 }
400 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
401 return reverse_iterator(begin());
402 }
403 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
404 return const_reverse_iterator(begin());
405 }
406
407 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT {
408 return begin();
409 }
410 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT {
411 return end();
412 }
413 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator
414 crbegin() const _NOEXCEPT {
415 return rbegin();
416 }
417 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT {
418 return rend();
419 }
420
421 // capacity:
422 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return 0; }
423 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return 0; }
424 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return true; }
425
426 // element access:
427 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type) _NOEXCEPT {
428 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
429 __libcpp_unreachable();
430 }
431
432 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference
433 operator[](size_type) const _NOEXCEPT {
434 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
435 __libcpp_unreachable();
436 }
437
438 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type) {
439 std::__throw_out_of_range(msg: "array<T, 0>::at");
440 __libcpp_unreachable();
441 }
442
443 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type) const {
444 std::__throw_out_of_range(msg: "array<T, 0>::at");
445 __libcpp_unreachable();
446 }
447
448 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT {
449 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
450 __libcpp_unreachable();
451 }
452
453 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT {
454 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
455 __libcpp_unreachable();
456 }
457
458 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT {
459 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
460 __libcpp_unreachable();
461 }
462
463 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
464 _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
465 __libcpp_unreachable();
466 }
467};
468
469# if _LIBCPP_STD_VER >= 17
470template <class _Tp, class... _Args, class = enable_if_t<__all<_IsSame<_Tp, _Args>::value...>::value> >
471array(_Tp, _Args...) -> array<_Tp, 1 + sizeof...(_Args)>;
472# endif
473
474template <class _Tp, size_t _Size>
475inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
476operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
477 return std::equal(__x.begin(), __x.end(), __y.begin());
478}
479
480# if _LIBCPP_STD_VER <= 17
481
482template <class _Tp, size_t _Size>
483inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
484 return !(__x == __y);
485}
486
487template <class _Tp, size_t _Size>
488inline _LIBCPP_HIDE_FROM_ABI bool operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
489 return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
490}
491
492template <class _Tp, size_t _Size>
493inline _LIBCPP_HIDE_FROM_ABI bool operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
494 return __y < __x;
495}
496
497template <class _Tp, size_t _Size>
498inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
499 return !(__y < __x);
500}
501
502template <class _Tp, size_t _Size>
503inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
504 return !(__x < __y);
505}
506
507# else // _LIBCPP_STD_VER <= 17
508
509template <class _Tp, size_t _Size>
510_LIBCPP_HIDE_FROM_ABI constexpr __synth_three_way_result<_Tp>
511operator<=>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
512 return std::lexicographical_compare_three_way(__x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
513}
514
515# endif // _LIBCPP_STD_VER <= 17
516
517template <class _Tp, size_t _Size, __enable_if_t<_Size == 0 || __is_swappable_v<_Tp>, int> = 0>
518inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
519 _NOEXCEPT_(noexcept(__x.swap(__y))) {
520 __x.swap(__y);
521}
522
523template <class _Tp, size_t _Size>
524struct tuple_size<array<_Tp, _Size> > : public integral_constant<size_t, _Size> {};
525
526template <size_t _Ip, class _Tp, size_t _Size>
527struct tuple_element<_Ip, array<_Tp, _Size> > {
528 static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
529 using type _LIBCPP_NODEBUG = _Tp;
530};
531
532template <size_t _Ip, class _Tp, size_t _Size>
533[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&
534get(array<_Tp, _Size>& __a) _NOEXCEPT {
535 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
536 return __a.__elems_[_Ip];
537}
538
539template <size_t _Ip, class _Tp, size_t _Size>
540[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&
541get(const array<_Tp, _Size>& __a) _NOEXCEPT {
542 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
543 return __a.__elems_[_Ip];
544}
545
546template <size_t _Ip, class _Tp, size_t _Size>
547[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&&
548get(array<_Tp, _Size>&& __a) _NOEXCEPT {
549 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
550 return std::move(__a.__elems_[_Ip]);
551}
552
553template <size_t _Ip, class _Tp, size_t _Size>
554[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&&
555get(const array<_Tp, _Size>&& __a) _NOEXCEPT {
556 static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
557 return std::move(__a.__elems_[_Ip]);
558}
559
560# if _LIBCPP_STD_VER >= 20
561
562template <typename _Tp, size_t _Size, size_t... _Index>
563_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
564__to_array_lvalue_impl(_Tp (&__arr)[_Size], index_sequence<_Index...>) {
565 return {{__arr[_Index]...}};
566}
567
568template <typename _Tp, size_t _Size, size_t... _Index>
569_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
570__to_array_rvalue_impl(_Tp (&&__arr)[_Size], index_sequence<_Index...>) {
571 return {{std::move(__arr[_Index])...}};
572}
573
574template <typename _Tp, size_t _Size>
575[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
576to_array(_Tp (&__arr)[_Size]) noexcept(is_nothrow_constructible_v<_Tp, _Tp&>) {
577 static_assert(!is_array_v<_Tp>, "[array.creation]/1: to_array does not accept multidimensional arrays.");
578 static_assert(is_constructible_v<_Tp, _Tp&>, "[array.creation]/1: to_array requires copy constructible elements.");
579 return std::__to_array_lvalue_impl(__arr, make_index_sequence<_Size>());
580}
581
582template <typename _Tp, size_t _Size>
583[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
584to_array(_Tp (&&__arr)[_Size]) noexcept(is_nothrow_move_constructible_v<_Tp>) {
585 static_assert(!is_array_v<_Tp>, "[array.creation]/4: to_array does not accept multidimensional arrays.");
586 static_assert(is_move_constructible_v<_Tp>, "[array.creation]/4: to_array requires move constructible elements.");
587 return std::__to_array_rvalue_impl(std::move(__arr), make_index_sequence<_Size>());
588}
589
590# endif // _LIBCPP_STD_VER >= 20
591
592_LIBCPP_END_NAMESPACE_STD
593
594_LIBCPP_POP_MACROS
595
596#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
597
598#endif // _LIBCPP_ARRAY
599