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> // all public C++ headers provide the assertion handler
120#include <__config>
121#include <__fwd/array.h>
122#include <__iterator/reverse_iterator.h>
123#include <__tuple/sfinae_helpers.h>
124#include <__type_traits/conditional.h>
125#include <__type_traits/is_array.h>
126#include <__type_traits/is_const.h>
127#include <__type_traits/is_constructible.h>
128#include <__type_traits/is_move_constructible.h>
129#include <__type_traits/is_nothrow_constructible.h>
130#include <__type_traits/is_nothrow_move_constructible.h>
131#include <__type_traits/is_same.h>
132#include <__type_traits/is_swappable.h>
133#include <__type_traits/remove_cv.h>
134#include <__utility/empty.h>
135#include <__utility/integer_sequence.h>
136#include <__utility/move.h>
137#include <__utility/unreachable.h>
138#include <stdexcept>
139#include <version>
140
141// standard-mandated includes
142
143// [iterator.range]
144#include <__iterator/access.h>
145#include <__iterator/data.h>
146#include <__iterator/empty.h>
147#include <__iterator/reverse_access.h>
148#include <__iterator/size.h>
149
150// [array.syn]
151#include <compare>
152#include <initializer_list>
153
154// [tuple.helper]
155#include <__tuple/tuple_element.h>
156#include <__tuple/tuple_size.h>
157
158#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
159#  pragma GCC system_header
160#endif
161
162_LIBCPP_BEGIN_NAMESPACE_STD
163
164template <class _Tp, size_t _Size>
165struct _LIBCPP_TEMPLATE_VIS array {
166  // types:
167  using __self                 = array;
168  using value_type             = _Tp;
169  using reference              = value_type&;
170  using const_reference        = const value_type&;
171  using iterator               = value_type*;
172  using const_iterator         = const value_type*;
173  using pointer                = value_type*;
174  using const_pointer          = const value_type*;
175  using size_type              = size_t;
176  using difference_type        = ptrdiff_t;
177  using reverse_iterator       = std::reverse_iterator<iterator>;
178  using const_reverse_iterator = std::reverse_iterator<const_iterator>;
179
180  _Tp __elems_[_Size];
181
182  // No explicit construct/copy/destroy for aggregate type
183  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type& __u) {
184    std::fill_n(data(), _Size, __u);
185  }
186
187  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array& __a)
188      _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) {
189    std::swap_ranges(data(), data() + _Size, __a.data());
190  }
191
192  // iterators:
193  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT { return iterator(data()); }
194  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
195    return const_iterator(data());
196  }
197  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT { return iterator(data() + _Size); }
198  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
199    return const_iterator(data() + _Size);
200  }
201
202  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
203    return reverse_iterator(end());
204  }
205  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rbegin() const _NOEXCEPT {
206    return const_reverse_iterator(end());
207  }
208  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
209    return reverse_iterator(begin());
210  }
211  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
212    return const_reverse_iterator(begin());
213  }
214
215  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT { return begin(); }
216  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT { return end(); }
217  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crbegin() const _NOEXCEPT {
218    return rbegin();
219  }
220  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
221
222  // capacity:
223  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return _Size; }
224  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return _Size; }
225  _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {
226    return _Size == 0;
227  }
228
229  // element access:
230  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type __n) _NOEXCEPT {
231    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
232    return __elems_[__n];
233  }
234  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference operator[](size_type __n) const _NOEXCEPT {
235    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < _Size, "out-of-bounds access in std::array<T, N>");
236    return __elems_[__n];
237  }
238
239  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type __n) {
240    if (__n >= _Size)
241      __throw_out_of_range("array::at");
242    return __elems_[__n];
243  }
244
245  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type __n) const {
246    if (__n >= _Size)
247      __throw_out_of_range("array::at");
248    return __elems_[__n];
249  }
250
251  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT { return (*this)[0]; }
252  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT { return (*this)[0]; }
253  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT { return (*this)[_Size - 1]; }
254  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
255    return (*this)[_Size - 1];
256  }
257
258  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return __elems_; }
259  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT { return __elems_; }
260};
261
262template <class _Tp>
263struct _LIBCPP_TEMPLATE_VIS array<_Tp, 0> {
264  // types:
265  typedef array __self;
266  typedef _Tp value_type;
267  typedef value_type& reference;
268  typedef const value_type& const_reference;
269  typedef value_type* iterator;
270  typedef const value_type* const_iterator;
271  typedef value_type* pointer;
272  typedef const value_type* const_pointer;
273  typedef size_t size_type;
274  typedef ptrdiff_t difference_type;
275  typedef std::reverse_iterator<iterator> reverse_iterator;
276  typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
277
278  typedef __conditional_t<is_const<_Tp>::value, const __empty, __empty> _EmptyType;
279
280  struct _ArrayInStructT {
281    _Tp __data_[1];
282  };
283  _ALIGNAS_TYPE(_ArrayInStructT) _EmptyType __elems_[sizeof(_ArrayInStructT)];
284
285  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 value_type* data() _NOEXCEPT { return nullptr; }
286  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const value_type* data() const _NOEXCEPT { return nullptr; }
287
288  // No explicit construct/copy/destroy for aggregate type
289  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void fill(const value_type&) {
290    static_assert(!is_const<_Tp>::value, "cannot fill zero-sized array of type 'const T'");
291  }
292
293  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array&) _NOEXCEPT {
294    static_assert(!is_const<_Tp>::value, "cannot swap zero-sized array of type 'const T'");
295  }
296
297  // iterators:
298  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator begin() _NOEXCEPT { return iterator(data()); }
299  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator begin() const _NOEXCEPT {
300    return const_iterator(data());
301  }
302  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 iterator end() _NOEXCEPT { return iterator(data()); }
303  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator end() const _NOEXCEPT {
304    return const_iterator(data());
305  }
306
307  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rbegin() _NOEXCEPT {
308    return reverse_iterator(end());
309  }
310  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rbegin() const _NOEXCEPT {
311    return const_reverse_iterator(end());
312  }
313  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator rend() _NOEXCEPT {
314    return reverse_iterator(begin());
315  }
316  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator rend() const _NOEXCEPT {
317    return const_reverse_iterator(begin());
318  }
319
320  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cbegin() const _NOEXCEPT { return begin(); }
321  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_iterator cend() const _NOEXCEPT { return end(); }
322  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crbegin() const _NOEXCEPT {
323    return rbegin();
324  }
325  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 const_reverse_iterator crend() const _NOEXCEPT { return rend(); }
326
327  // capacity:
328  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT { return 0; }
329  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT { return 0; }
330  _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT { return true; }
331
332  // element access:
333  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](size_type) _NOEXCEPT {
334    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
335    __libcpp_unreachable();
336  }
337
338  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference operator[](size_type) const _NOEXCEPT {
339    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
340    __libcpp_unreachable();
341  }
342
343  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference at(size_type) {
344    __throw_out_of_range("array<T, 0>::at");
345    __libcpp_unreachable();
346  }
347
348  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference at(size_type) const {
349    __throw_out_of_range("array<T, 0>::at");
350    __libcpp_unreachable();
351  }
352
353  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference front() _NOEXCEPT {
354    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
355    __libcpp_unreachable();
356  }
357
358  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference front() const _NOEXCEPT {
359    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::front() on a zero-sized array");
360    __libcpp_unreachable();
361  }
362
363  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference back() _NOEXCEPT {
364    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
365    __libcpp_unreachable();
366  }
367
368  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const_reference back() const _NOEXCEPT {
369    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(false, "cannot call array<T, 0>::back() on a zero-sized array");
370    __libcpp_unreachable();
371  }
372};
373
374#if _LIBCPP_STD_VER >= 17
375template <class _Tp, class... _Args, class = enable_if_t<__all<_IsSame<_Tp, _Args>::value...>::value> >
376array(_Tp, _Args...) -> array<_Tp, 1 + sizeof...(_Args)>;
377#endif
378
379template <class _Tp, size_t _Size>
380inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
381operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
382  return std::equal(__x.begin(), __x.end(), __y.begin());
383}
384
385#if _LIBCPP_STD_VER <= 17
386
387template <class _Tp, size_t _Size>
388inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
389  return !(__x == __y);
390}
391
392template <class _Tp, size_t _Size>
393inline _LIBCPP_HIDE_FROM_ABI bool operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
394  return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
395}
396
397template <class _Tp, size_t _Size>
398inline _LIBCPP_HIDE_FROM_ABI bool operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
399  return __y < __x;
400}
401
402template <class _Tp, size_t _Size>
403inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
404  return !(__y < __x);
405}
406
407template <class _Tp, size_t _Size>
408inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
409  return !(__x < __y);
410}
411
412#else // _LIBCPP_STD_VER <= 17
413
414template <class _Tp, size_t _Size>
415_LIBCPP_HIDE_FROM_ABI constexpr __synth_three_way_result<_Tp>
416operator<=>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y) {
417  return std::lexicographical_compare_three_way(
418      __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way<_Tp, _Tp>);
419}
420
421#endif // _LIBCPP_STD_VER <= 17
422
423template <class _Tp, size_t _Size, __enable_if_t<_Size == 0 || __is_swappable<_Tp>::value, int> = 0>
424inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
425    _NOEXCEPT_(noexcept(__x.swap(__y))) {
426  __x.swap(__y);
427}
428
429template <class _Tp, size_t _Size>
430struct _LIBCPP_TEMPLATE_VIS tuple_size<array<_Tp, _Size> > : public integral_constant<size_t, _Size> {};
431
432template <size_t _Ip, class _Tp, size_t _Size>
433struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, array<_Tp, _Size> > {
434  static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
435  typedef _Tp type;
436};
437
438template <size_t _Ip, class _Tp, size_t _Size>
439inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp& get(array<_Tp, _Size>& __a) _NOEXCEPT {
440  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
441  return __a.__elems_[_Ip];
442}
443
444template <size_t _Ip, class _Tp, size_t _Size>
445inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp& get(const array<_Tp, _Size>& __a) _NOEXCEPT {
446  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
447  return __a.__elems_[_Ip];
448}
449
450template <size_t _Ip, class _Tp, size_t _Size>
451inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp&& get(array<_Tp, _Size>&& __a) _NOEXCEPT {
452  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
453  return std::move(__a.__elems_[_Ip]);
454}
455
456template <size_t _Ip, class _Tp, size_t _Size>
457inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Tp&& get(const array<_Tp, _Size>&& __a) _NOEXCEPT {
458  static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
459  return std::move(__a.__elems_[_Ip]);
460}
461
462#if _LIBCPP_STD_VER >= 20
463
464template <typename _Tp, size_t _Size, size_t... _Index>
465_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
466__to_array_lvalue_impl(_Tp (&__arr)[_Size], index_sequence<_Index...>) {
467  return {{__arr[_Index]...}};
468}
469
470template <typename _Tp, size_t _Size, size_t... _Index>
471_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
472__to_array_rvalue_impl(_Tp (&&__arr)[_Size], index_sequence<_Index...>) {
473  return {{std::move(__arr[_Index])...}};
474}
475
476template <typename _Tp, size_t _Size>
477_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
478to_array(_Tp (&__arr)[_Size]) noexcept(is_nothrow_constructible_v<_Tp, _Tp&>) {
479  static_assert(!is_array_v<_Tp>, "[array.creation]/1: to_array does not accept multidimensional arrays.");
480  static_assert(is_constructible_v<_Tp, _Tp&>, "[array.creation]/1: to_array requires copy constructible elements.");
481  return std::__to_array_lvalue_impl(__arr, make_index_sequence<_Size>());
482}
483
484template <typename _Tp, size_t _Size>
485_LIBCPP_HIDE_FROM_ABI constexpr array<remove_cv_t<_Tp>, _Size>
486to_array(_Tp (&&__arr)[_Size]) noexcept(is_nothrow_move_constructible_v<_Tp>) {
487  static_assert(!is_array_v<_Tp>, "[array.creation]/4: to_array does not accept multidimensional arrays.");
488  static_assert(is_move_constructible_v<_Tp>, "[array.creation]/4: to_array requires move constructible elements.");
489  return std::__to_array_rvalue_impl(std::move(__arr), make_index_sequence<_Size>());
490}
491
492#endif // _LIBCPP_STD_VER >= 20
493
494_LIBCPP_END_NAMESPACE_STD
495
496#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
497#  include <algorithm>
498#  include <concepts>
499#  include <cstdlib>
500#  include <iterator>
501#  include <type_traits>
502#  include <utility>
503#endif
504
505#endif // _LIBCPP_ARRAY
506