xref: /llvm-project/libcxx/include/array (revision 1ba8ed0cd7d03ed9b70aaf32b3d8e9205ef95ef2)
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    typedef T & reference;
23    typedef const T & const_reference;
24    typedef implementation defined iterator;
25    typedef implementation defined const_iterator;
26    typedef size_t size_type;
27    typedef ptrdiff_t difference_type;
28    typedef T value_type;
29    typedef T* pointer;
30    typedef const T* const_pointer;
31    typedef std::reverse_iterator<iterator> reverse_iterator;
32    typedef std::reverse_iterator<const_iterator> const_reverse_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#include <__algorithm/equal.h>
115#include <__algorithm/fill_n.h>
116#include <__algorithm/lexicographical_compare.h>
117#include <__algorithm/lexicographical_compare_three_way.h>
118#include <__algorithm/swap_ranges.h>
119#include <__assert>
120#include <__config>
121#include <__fwd/array.h>
122#include <__iterator/reverse_iterator.h>
123#include <__iterator/wrap_iter.h>
124#include <__tuple/sfinae_helpers.h>
125#include <__type_traits/conditional.h>
126#include <__type_traits/conjunction.h>
127#include <__type_traits/is_array.h>
128#include <__type_traits/is_const.h>
129#include <__type_traits/is_constructible.h>
130#include <__type_traits/is_nothrow_constructible.h>
131#include <__type_traits/is_same.h>
132#include <__type_traits/is_swappable.h>
133#include <__type_traits/is_trivially_relocatable.h>
134#include <__type_traits/remove_cv.h>
135#include <__utility/empty.h>
136#include <__utility/integer_sequence.h>
137#include <__utility/move.h>
138#include <__utility/unreachable.h>
139#include <stdexcept>
140#include <version>
141
142// standard-mandated includes
143
144// [iterator.range]
145#include <__iterator/access.h>
146#include <__iterator/data.h>
147#include <__iterator/empty.h>
148#include <__iterator/reverse_access.h>
149#include <__iterator/size.h>
150
151// [array.syn]
152#include <compare>
153#include <initializer_list>
154
155// [tuple.helper]
156#include <__tuple/tuple_element.h>
157#include <__tuple/tuple_size.h>
158
159#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
160#  pragma GCC system_header
161#endif
162
163_LIBCPP_PUSH_MACROS
164#include <__undef_macros>
165
166_LIBCPP_BEGIN_NAMESPACE_STD
167
168template <class _Tp, size_t _Size>
169struct _LIBCPP_TEMPLATE_VIS array {
170  using __trivially_relocatable = __conditional_t<__libcpp_is_trivially_relocatable<_Tp>::value, array, void>;
171
172  // types:
173  using __self          = array;
174  using value_type      = _Tp;
175  using reference       = value_type&;
176  using const_reference = const value_type&;
177  using pointer         = value_type*;
178  using const_pointer   = const value_type*;
179#if defined(_LIBCPP_ABI_USE_WRAP_ITER_IN_STD_ARRAY)
180  using iterator       = __wrap_iter<pointer>;
181  using const_iterator = __wrap_iter<const_pointer>;
182#else
183  using iterator       = pointer;
184  using const_iterator = const_pointer;
185#endif
186  using size_type              = size_t;
187  using difference_type        = ptrdiff_t;
188  using reverse_iterator       = std::reverse_iterator<iterator>;
189  using const_reverse_iterator = std::reverse_iterator<const_iterator>;
190
191  _Tp __elems_[_Size];
192
193  // No explicit construct/copy/destroy for aggregate type
194  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type& __u) {
195    std::fill_n(data(), _Size, __u);
196  }
197
198  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array& __a)
199      _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) {
200    std::swap_ranges(data(), data() + _Size, __a.data());
201  }
202
203  // iterators:
204  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT { return iterator(data()); }
205  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
206    return const_iterator(data());
207  }
208  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT { return iterator(data() + _Size); }
209  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
210    return const_iterator(data() + _Size);
211  }
212
213  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
214    return reverse_iterator(end());
215  }
216  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rbegin() const _NOEXCEPT {
217    return const_reverse_iterator(end());
218  }
219  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
220    return reverse_iterator(begin());
221  }
222  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
223    return const_reverse_iterator(begin());
224  }
225
226  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT { return begin(); }
227  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT { return end(); }
228  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crbegin() const _NOEXCEPT {
229    return rbegin();
230  }
231  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
232
233  // capacity:
234  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return _Size; }
235  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return _Size; }
236  _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {
237    return _Size == 0;
238  }
239
240  // element access:
241  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type __n) _NOEXCEPT {
242    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
243    return __elems_[__n];
244  }
245  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference operator[](size_type __n) const _NOEXCEPT {
246    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
247    return __elems_[__n];
248  }
249
250  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type __n) {
251    if (__n >= _Size)
252      __throw_out_of_range("array::at");
253    return __elems_[__n];
254  }
255
256  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type __n) const {
257    if (__n >= _Size)
258      __throw_out_of_range("array::at");
259    return __elems_[__n];
260  }
261
262  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT { return (*this)[0]; }
263  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT { return (*this)[0]; }
264  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT { return (*this)[_Size - 1]; }
265  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
266    return (*this)[_Size - 1];
267  }
268
269  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return __elems_; }
270  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT { return __elems_; }
271};
272
273template <class _Tp>
274struct _LIBCPP_TEMPLATE_VIS array<_Tp, 0> {
275  // types:
276  typedef array __self;
277  typedef _Tp value_type;
278  typedef value_type& reference;
279  typedef const value_type& const_reference;
280  typedef value_type* iterator;
281  typedef const value_type* const_iterator;
282  typedef value_type* pointer;
283  typedef const value_type* const_pointer;
284  typedef size_t size_type;
285  typedef ptrdiff_t difference_type;
286  typedef std::reverse_iterator<iterator> reverse_iterator;
287  typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
288
289  typedef __conditional_t<is_const<_Tp>::value, const __empty, __empty> _EmptyType;
290
291  struct _ArrayInStructT {
292    _Tp __data_[1];
293  };
294  _ALIGNAS_TYPE(_ArrayInStructT) _EmptyType __elems_[sizeof(_ArrayInStructT)];
295
296  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return nullptr; }
297  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT { return nullptr; }
298
299  // No explicit construct/copy/destroy for aggregate type
300  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type&) {
301    static_assert(!is_const<_Tp>::value, "cannot fill zero-sized array of type 'const T'");
302  }
303
304  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array&) _NOEXCEPT {
305    static_assert(!is_const<_Tp>::value, "cannot swap zero-sized array of type 'const T'");
306  }
307
308  // iterators:
309  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT { return iterator(data()); }
310  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
311    return const_iterator(data());
312  }
313  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT { return iterator(data()); }
314  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
315    return const_iterator(data());
316  }
317
318  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
319    return reverse_iterator(end());
320  }
321  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rbegin() const _NOEXCEPT {
322    return const_reverse_iterator(end());
323  }
324  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
325    return reverse_iterator(begin());
326  }
327  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
328    return const_reverse_iterator(begin());
329  }
330
331  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT { return begin(); }
332  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT { return end(); }
333  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crbegin() const _NOEXCEPT {
334    return rbegin();
335  }
336  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
337
338  // capacity:
339  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return 0; }
340  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return 0; }
341  _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return true; }
342
343  // element access:
344  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type) _NOEXCEPT {
345    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
346    __libcpp_unreachable();
347  }
348
349  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference operator[](size_type) const _NOEXCEPT {
350    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
351    __libcpp_unreachable();
352  }
353
354  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type) {
355    __throw_out_of_range("array<T, 0>::at");
356    __libcpp_unreachable();
357  }
358
359  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type) const {
360    __throw_out_of_range("array<T, 0>::at");
361    __libcpp_unreachable();
362  }
363
364  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT {
365    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
366    __libcpp_unreachable();
367  }
368
369  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT {
370    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
371    __libcpp_unreachable();
372  }
373
374  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT {
375    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
376    __libcpp_unreachable();
377  }
378
379  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
380    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
381    __libcpp_unreachable();
382  }
383};
384
385#if _LIBCPP_STD_VER >= 17
386template <class _Tp, class... _Args, class = enable_if_t<__all<_IsSame<_Tp, _Args>::value...>::value> >
387array(_Tp, _Args...) -> array<_Tp, 1 + sizeof...(_Args)>;
388#endif
389
390template <class _Tp, size_t _Size>
391inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
392operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
393  return std::equal(__x.begin(), __x.end(), __y.begin());
394}
395
396#if _LIBCPP_STD_VER <= 17
397
398template <class _Tp, size_t _Size>
399inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
400  return !(__x == __y);
401}
402
403template <class _Tp, size_t _Size>
404inline _LIBCPP_HIDE_FROM_ABI bool operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
405  return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
406}
407
408template <class _Tp, size_t _Size>
409inline _LIBCPP_HIDE_FROM_ABI bool operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
410  return __y < __x;
411}
412
413template <class _Tp, size_t _Size>
414inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
415  return !(__y < __x);
416}
417
418template <class _Tp, size_t _Size>
419inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
420  return !(__x < __y);
421}
422
423#else // _LIBCPP_STD_VER <= 17
424
425template <class _Tp, size_t _Size>
426_LIBCPP_HIDE_FROM_ABI constexpr __synth_three_way_result<_Tp>
427operator<=>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
428  return std::lexicographical_compare_three_way(
429      __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way<_Tp, _Tp>);
430}
431
432#endif // _LIBCPP_STD_VER <= 17
433
434template <class _Tp, size_t _Size, __enable_if_t<_Size == 0 || __is_swappable<_Tp>::value, int> = 0>
435inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
436    _NOEXCEPT_(noexcept(__x.swap(__y))) {
437  __x.swap(__y);
438}
439
440template <class _Tp, size_t _Size>
441struct _LIBCPP_TEMPLATE_VIS tuple_size<array<_Tp, _Size> > : public integral_constant<size_t, _Size> {};
442
443template <size_t _Ip, class _Tp, size_t _Size>
444struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, array<_Tp, _Size> > {
445  static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
446  typedef _Tp type;
447};
448
449template <size_t _Ip, class _Tp, size_t _Size>
450inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp& get(array<_Tp, _Size>& __a) _NOEXCEPT {
451  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
452  return __a.__elems_[_Ip];
453}
454
455template <size_t _Ip, class _Tp, size_t _Size>
456inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp& get(const array<_Tp, _Size>& __a) _NOEXCEPT {
457  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
458  return __a.__elems_[_Ip];
459}
460
461template <size_t _Ip, class _Tp, size_t _Size>
462inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&& get(array<_Tp, _Size>&& __a) _NOEXCEPT {
463  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
464  return std::move(__a.__elems_[_Ip]);
465}
466
467template <size_t _Ip, class _Tp, size_t _Size>
468inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&& get(const array<_Tp, _Size>&& __a) _NOEXCEPT {
469  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
470  return std::move(__a.__elems_[_Ip]);
471}
472
473#if _LIBCPP_STD_VER >= 20
474
475template <typename _Tp, size_t _Size, size_t... _Index>
476_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
477__to_array_lvalue_impl(_Tp (&__arr)[_Size], index_sequence<_Index...>) {
478  return {{__arr[_Index]...}};
479}
480
481template <typename _Tp, size_t _Size, size_t... _Index>
482_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
483__to_array_rvalue_impl(_Tp (&&__arr)[_Size], index_sequence<_Index...>) {
484  return {{std::move(__arr[_Index])...}};
485}
486
487template <typename _Tp, size_t _Size>
488_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
489to_array(_Tp (&__arr)[_Size]) noexcept(is_nothrow_constructible_v<_Tp, _Tp&>) {
490  static_assert(!is_array_v<_Tp>, "[array.creation]/1: to_array does not accept multidimensional arrays.");
491  static_assert(is_constructible_v<_Tp, _Tp&>, "[array.creation]/1: to_array requires copy constructible elements.");
492  return std::__to_array_lvalue_impl(__arr, make_index_sequence<_Size>());
493}
494
495template <typename _Tp, size_t _Size>
496_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
497to_array(_Tp (&&__arr)[_Size]) noexcept(is_nothrow_move_constructible_v<_Tp>) {
498  static_assert(!is_array_v<_Tp>, "[array.creation]/4: to_array does not accept multidimensional arrays.");
499  static_assert(is_move_constructible_v<_Tp>, "[array.creation]/4: to_array requires move constructible elements.");
500  return std::__to_array_rvalue_impl(std::move(__arr), make_index_sequence<_Size>());
501}
502
503#endif // _LIBCPP_STD_VER >= 20
504
505_LIBCPP_END_NAMESPACE_STD
506
507_LIBCPP_POP_MACROS
508
509#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
510#  include <algorithm>
511#  include <concepts>
512#  include <cstdlib>
513#  include <iterator>
514#  include <type_traits>
515#  include <utility>
516#endif
517
518#endif // _LIBCPP_ARRAY
519