xref: /llvm-project-15.0.7/libcxx/include/array (revision 4e0ea2cf)
13e519524SHoward Hinnant// -*- C++ -*-
23e519524SHoward Hinnant//===---------------------------- array -----------------------------------===//
33e519524SHoward Hinnant//
457b08b09SChandler Carruth// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
557b08b09SChandler Carruth// See https://llvm.org/LICENSE.txt for license information.
657b08b09SChandler Carruth// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
73e519524SHoward Hinnant//
83e519524SHoward Hinnant//===----------------------------------------------------------------------===//
93e519524SHoward Hinnant
103e519524SHoward Hinnant#ifndef _LIBCPP_ARRAY
113e519524SHoward Hinnant#define _LIBCPP_ARRAY
123e519524SHoward Hinnant
133e519524SHoward Hinnant/*
143e519524SHoward Hinnant    array synopsis
153e519524SHoward Hinnant
163e519524SHoward Hinnantnamespace std
173e519524SHoward Hinnant{
183e519524SHoward Hinnanttemplate <class T, size_t N >
193e519524SHoward Hinnantstruct array
203e519524SHoward Hinnant{
213e519524SHoward Hinnant    // types:
223e519524SHoward Hinnant    typedef T & reference;
233e519524SHoward Hinnant    typedef const T & const_reference;
243e519524SHoward Hinnant    typedef implementation defined iterator;
253e519524SHoward Hinnant    typedef implementation defined const_iterator;
263e519524SHoward Hinnant    typedef size_t size_type;
273e519524SHoward Hinnant    typedef ptrdiff_t difference_type;
283e519524SHoward Hinnant    typedef T value_type;
293e519524SHoward Hinnant    typedef T* pointer;
303e519524SHoward Hinnant    typedef const T* const_pointer;
313e519524SHoward Hinnant    typedef std::reverse_iterator<iterator> reverse_iterator;
323e519524SHoward Hinnant    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
333e519524SHoward Hinnant
343e519524SHoward Hinnant    // No explicit construct/copy/destroy for aggregate type
3577b9abfcSLouis Dionne    void fill(const T& u);                                      // constexpr in C++20
3677b9abfcSLouis Dionne    void swap(array& a) noexcept(is_nothrow_swappable_v<T>);    // constexpr in C++20
373e519524SHoward Hinnant
383e519524SHoward Hinnant    // iterators:
3977b9abfcSLouis Dionne    iterator begin() noexcept;                                  // constexpr in C++17
4077b9abfcSLouis Dionne    const_iterator begin() const noexcept;                      // constexpr in C++17
4177b9abfcSLouis Dionne    iterator end() noexcept;                                    // constexpr in C++17
4277b9abfcSLouis Dionne    const_iterator end() const noexcept;                        // constexpr in C++17
433e519524SHoward Hinnant
4477b9abfcSLouis Dionne    reverse_iterator rbegin() noexcept;                         // constexpr in C++17
4577b9abfcSLouis Dionne    const_reverse_iterator rbegin() const noexcept;             // constexpr in C++17
4677b9abfcSLouis Dionne    reverse_iterator rend() noexcept;                           // constexpr in C++17
4777b9abfcSLouis Dionne    const_reverse_iterator rend() const noexcept;               // constexpr in C++17
483e519524SHoward Hinnant
4977b9abfcSLouis Dionne    const_iterator cbegin() const noexcept;                     // constexpr in C++17
5077b9abfcSLouis Dionne    const_iterator cend() const noexcept;                       // constexpr in C++17
5177b9abfcSLouis Dionne    const_reverse_iterator crbegin() const noexcept;            // constexpr in C++17
5277b9abfcSLouis Dionne    const_reverse_iterator crend() const noexcept;              // constexpr in C++17
533e519524SHoward Hinnant
543e519524SHoward Hinnant    // capacity:
558f0cd597SHoward Hinnant    constexpr size_type size() const noexcept;
568f0cd597SHoward Hinnant    constexpr size_type max_size() const noexcept;
57397717b7SHoward Hinnant    constexpr bool empty() const noexcept;
583e519524SHoward Hinnant
593e519524SHoward Hinnant    // element access:
6077b9abfcSLouis Dionne    reference operator[](size_type n);                          // constexpr in C++17
618bf1f08aSMarshall Clow    const_reference operator[](size_type n) const;              // constexpr in C++14
6277b9abfcSLouis Dionne    reference at(size_type n);                                  // constexpr in C++17
638bf1f08aSMarshall Clow    const_reference at(size_type n) const;                      // constexpr in C++14
643e519524SHoward Hinnant
6577b9abfcSLouis Dionne    reference front();                                          // constexpr in C++17
668bf1f08aSMarshall Clow    const_reference front() const;                              // constexpr in C++14
6777b9abfcSLouis Dionne    reference back();                                           // constexpr in C++17
688bf1f08aSMarshall Clow    const_reference back() const;                               // constexpr in C++14
693e519524SHoward Hinnant
7077b9abfcSLouis Dionne    T* data() noexcept;                                         // constexpr in C++17
7177b9abfcSLouis Dionne    const T* data() const noexcept;                             // constexpr in C++17
723e519524SHoward Hinnant};
733e519524SHoward Hinnant
740ca8c089SMarshall Clowtemplate <class T, class... U>
7577b9abfcSLouis Dionne  array(T, U...) -> array<T, 1 + sizeof...(U)>;                 // C++17
760ca8c089SMarshall Clow
773e519524SHoward Hinnanttemplate <class T, size_t N>
7877b9abfcSLouis Dionne  bool operator==(const array<T,N>& x, const array<T,N>& y);    // constexpr in C++20
793e519524SHoward Hinnanttemplate <class T, size_t N>
8077b9abfcSLouis Dionne  bool operator!=(const array<T,N>& x, const array<T,N>& y);    // constexpr in C++20
813e519524SHoward Hinnanttemplate <class T, size_t N>
8277b9abfcSLouis Dionne  bool operator<(const array<T,N>& x, const array<T,N>& y);     // constexpr in C++20
833e519524SHoward Hinnanttemplate <class T, size_t N>
8477b9abfcSLouis Dionne  bool operator>(const array<T,N>& x, const array<T,N>& y);     // constexpr in C++20
853e519524SHoward Hinnanttemplate <class T, size_t N>
8677b9abfcSLouis Dionne  bool operator<=(const array<T,N>& x, const array<T,N>& y);    // constexpr in C++20
873e519524SHoward Hinnanttemplate <class T, size_t N>
8877b9abfcSLouis Dionne  bool operator>=(const array<T,N>& x, const array<T,N>& y);    // constexpr in C++20
893e519524SHoward Hinnant
903e519524SHoward Hinnanttemplate <class T, size_t N >
9177b9abfcSLouis Dionne  void swap(array<T,N>& x, array<T,N>& y) noexcept(noexcept(x.swap(y))); // constexpr in C++20
9277b9abfcSLouis Dionne
9377b9abfcSLouis Dionnetemplate <class T, size_t N>
9477b9abfcSLouis Dionne  constexpr array<remove_cv_t<T>, N> to_array(T (&a)[N]);  // C++20
9577b9abfcSLouis Dionnetemplate <class T, size_t N>
9677b9abfcSLouis Dionne  constexpr array<remove_cv_t<T>, N> to_array(T (&&a)[N]); // C++20
973e519524SHoward Hinnant
98e4957601SMarshall Clowtemplate <class T> struct tuple_size;
992b0c7abbSLouis Dionnetemplate <size_t I, class T> struct tuple_element;
1003e519524SHoward Hinnanttemplate <class T, size_t N> struct tuple_size<array<T, N>>;
1015fcc8169SMarshall Clowtemplate <size_t I, class T, size_t N> struct tuple_element<I, array<T, N>>;
1025fcc8169SMarshall Clowtemplate <size_t I, class T, size_t N> T& get(array<T, N>&) noexcept;               // constexpr in C++14
1035fcc8169SMarshall Clowtemplate <size_t I, class T, size_t N> const T& get(const array<T, N>&) noexcept;   // constexpr in C++14
1045fcc8169SMarshall Clowtemplate <size_t I, class T, size_t N> T&& get(array<T, N>&&) noexcept;             // constexpr in C++14
105545b8861SEric Fiseliertemplate <size_t I, class T, size_t N> const T&& get(const array<T, N>&&) noexcept; // constexpr in C++14
1063e519524SHoward Hinnant
1073e519524SHoward Hinnant}  // std
1083e519524SHoward Hinnant
1093e519524SHoward Hinnant*/
1103e519524SHoward Hinnant
1113e519524SHoward Hinnant#include <__config>
112bfbd73f8SArthur O'Dwyer#include <__debug>
1133e519524SHoward Hinnant#include <__tuple>
114bfbd73f8SArthur O'Dwyer#include <algorithm>
115bfbd73f8SArthur O'Dwyer#include <cstdlib> // for _LIBCPP_UNREACHABLE
116bfbd73f8SArthur O'Dwyer#include <iterator>
117bfbd73f8SArthur O'Dwyer#include <stdexcept>
1183e519524SHoward Hinnant#include <type_traits>
1193e519524SHoward Hinnant#include <utility>
120f56972e2SMarshall Clow#include <version>
1213e519524SHoward Hinnant
122073458b1SHoward Hinnant#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
1233e519524SHoward Hinnant#pragma GCC system_header
124073458b1SHoward Hinnant#endif
1253e519524SHoward Hinnant
1263e519524SHoward Hinnant_LIBCPP_BEGIN_NAMESPACE_STD
1273e519524SHoward Hinnant
1283e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
129e2f2d1edSEric Fiselierstruct _LIBCPP_TEMPLATE_VIS array
1303e519524SHoward Hinnant{
1313e519524SHoward Hinnant    // types:
1323e519524SHoward Hinnant    typedef array __self;
1333e519524SHoward Hinnant    typedef _Tp                                   value_type;
1343e519524SHoward Hinnant    typedef value_type&                           reference;
1353e519524SHoward Hinnant    typedef const value_type&                     const_reference;
1363e519524SHoward Hinnant    typedef value_type*                           iterator;
1373e519524SHoward Hinnant    typedef const value_type*                     const_iterator;
1383e519524SHoward Hinnant    typedef value_type*                           pointer;
1393e519524SHoward Hinnant    typedef const value_type*                     const_pointer;
1403e519524SHoward Hinnant    typedef size_t                                size_type;
1413e519524SHoward Hinnant    typedef ptrdiff_t                             difference_type;
142d586f92cSArthur O'Dwyer    typedef _VSTD::reverse_iterator<iterator>       reverse_iterator;
143d586f92cSArthur O'Dwyer    typedef _VSTD::reverse_iterator<const_iterator> const_reverse_iterator;
1443e519524SHoward Hinnant
14559cdf90aSEric Fiselier    _Tp __elems_[_Size];
1463e519524SHoward Hinnant
1473e519524SHoward Hinnant    // No explicit construct/copy/destroy for aggregate type
14877b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14977b9abfcSLouis Dionne    void fill(const value_type& __u) {
15066a14d15SLouis Dionne        _VSTD::fill_n(data(), _Size, __u);
15159cdf90aSEric Fiselier    }
152afeda5c2SEric Fiselier
15377b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15459cdf90aSEric Fiselier    void swap(array& __a) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) {
155d586f92cSArthur O'Dwyer        _VSTD::swap_ranges(data(), data() + _Size, __a.data());
15659cdf90aSEric Fiselier    }
1573e519524SHoward Hinnant
1583e519524SHoward Hinnant    // iterators:
159020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
16059cdf90aSEric Fiselier    iterator begin() _NOEXCEPT {return iterator(data());}
161020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
16259cdf90aSEric Fiselier    const_iterator begin() const _NOEXCEPT {return const_iterator(data());}
163020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
16459cdf90aSEric Fiselier    iterator end() _NOEXCEPT {return iterator(data() + _Size);}
165020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
16659cdf90aSEric Fiselier    const_iterator end() const _NOEXCEPT {return const_iterator(data() + _Size);}
1673e519524SHoward Hinnant
168020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1698f0cd597SHoward Hinnant    reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());}
170020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1718f0cd597SHoward Hinnant    const_reverse_iterator rbegin() const _NOEXCEPT {return const_reverse_iterator(end());}
172020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1738f0cd597SHoward Hinnant    reverse_iterator rend() _NOEXCEPT {return reverse_iterator(begin());}
174020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1758f0cd597SHoward Hinnant    const_reverse_iterator rend() const _NOEXCEPT {return const_reverse_iterator(begin());}
1763e519524SHoward Hinnant
177020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1788f0cd597SHoward Hinnant    const_iterator cbegin() const _NOEXCEPT {return begin();}
179020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1808f0cd597SHoward Hinnant    const_iterator cend() const _NOEXCEPT {return end();}
181020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1828f0cd597SHoward Hinnant    const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
183020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
1848f0cd597SHoward Hinnant    const_reverse_iterator crend() const _NOEXCEPT {return rend();}
1853e519524SHoward Hinnant
1863e519524SHoward Hinnant    // capacity:
1878f0cd597SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
188397717b7SHoward Hinnant    _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT {return _Size;}
1898f0cd597SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
190397717b7SHoward Hinnant    _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT {return _Size;}
19172c8fad4SMarshall Clow    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
19266a14d15SLouis Dionne    _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return _Size == 0;}
1933e519524SHoward Hinnant
1943e519524SHoward Hinnant    // element access:
195e7826950SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
19623776a17SLouis Dionne    reference operator[](size_type __n) _NOEXCEPT {
19723776a17SLouis Dionne        _LIBCPP_ASSERT(__n < _Size, "out-of-bounds access in std::array<T, N>");
19823776a17SLouis Dionne        return __elems_[__n];
19923776a17SLouis Dionne    }
200e7826950SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
20123776a17SLouis Dionne    const_reference operator[](size_type __n) const _NOEXCEPT {
20223776a17SLouis Dionne        _LIBCPP_ASSERT(__n < _Size, "out-of-bounds access in std::array<T, N>");
20323776a17SLouis Dionne        return __elems_[__n];
20423776a17SLouis Dionne    }
205e7826950SMarshall Clow
2060161874cSLouis Dionne    _LIBCPP_CONSTEXPR_AFTER_CXX14 reference at(size_type __n)
2070161874cSLouis Dionne    {
2080161874cSLouis Dionne        if (__n >= _Size)
2090161874cSLouis Dionne            __throw_out_of_range("array::at");
2100161874cSLouis Dionne        return __elems_[__n];
2110161874cSLouis Dionne    }
2120161874cSLouis Dionne
2130161874cSLouis Dionne    _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference at(size_type __n) const
2140161874cSLouis Dionne    {
2150161874cSLouis Dionne        if (__n >= _Size)
2160161874cSLouis Dionne            __throw_out_of_range("array::at");
2170161874cSLouis Dionne        return __elems_[__n];
2180161874cSLouis Dionne    }
2193e519524SHoward Hinnant
22023776a17SLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference front()             _NOEXCEPT {return (*this)[0];}
22123776a17SLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference front() const _NOEXCEPT {return (*this)[0];}
22223776a17SLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference back()              _NOEXCEPT {return (*this)[_Size - 1];}
22323776a17SLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference back() const  _NOEXCEPT {return (*this)[_Size - 1];}
2243e519524SHoward Hinnant
225020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
226936ff584SNirav Dave    value_type* data() _NOEXCEPT {return __elems_;}
227020b623aSMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
228936ff584SNirav Dave    const value_type* data() const _NOEXCEPT {return __elems_;}
2293e519524SHoward Hinnant};
2303e519524SHoward Hinnant
23159cdf90aSEric Fiseliertemplate <class _Tp>
23259cdf90aSEric Fiselierstruct _LIBCPP_TEMPLATE_VIS array<_Tp, 0>
23359cdf90aSEric Fiselier{
23459cdf90aSEric Fiselier    // types:
23559cdf90aSEric Fiselier    typedef array __self;
23659cdf90aSEric Fiselier    typedef _Tp                                   value_type;
23759cdf90aSEric Fiselier    typedef value_type&                           reference;
23859cdf90aSEric Fiselier    typedef const value_type&                     const_reference;
23959cdf90aSEric Fiselier    typedef value_type*                           iterator;
24059cdf90aSEric Fiselier    typedef const value_type*                     const_iterator;
24159cdf90aSEric Fiselier    typedef value_type*                           pointer;
24259cdf90aSEric Fiselier    typedef const value_type*                     const_pointer;
24359cdf90aSEric Fiselier    typedef size_t                                size_type;
24459cdf90aSEric Fiselier    typedef ptrdiff_t                             difference_type;
245d586f92cSArthur O'Dwyer    typedef _VSTD::reverse_iterator<iterator>       reverse_iterator;
246d586f92cSArthur O'Dwyer    typedef _VSTD::reverse_iterator<const_iterator> const_reverse_iterator;
24759cdf90aSEric Fiselier
24859cdf90aSEric Fiselier    typedef typename conditional<is_const<_Tp>::value, const char,
24959cdf90aSEric Fiselier                                char>::type _CharType;
2501a78ae3cSEric Fiselier
2511a78ae3cSEric Fiselier    struct  _ArrayInStructT { _Tp __data_[1]; };
2521a78ae3cSEric Fiselier    _ALIGNAS_TYPE(_ArrayInStructT) _CharType __elems_[sizeof(_ArrayInStructT)];
25359cdf90aSEric Fiselier
2547265ff92SLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2557265ff92SLouis Dionne    value_type* data() _NOEXCEPT {return nullptr;}
2567265ff92SLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2577265ff92SLouis Dionne    const value_type* data() const _NOEXCEPT {return nullptr;}
25877b9abfcSLouis Dionne
25959cdf90aSEric Fiselier    // No explicit construct/copy/destroy for aggregate type
26077b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
26177b9abfcSLouis Dionne    void fill(const value_type&) {
26259cdf90aSEric Fiselier      static_assert(!is_const<_Tp>::value,
26359cdf90aSEric Fiselier                    "cannot fill zero-sized array of type 'const T'");
26459cdf90aSEric Fiselier    }
26559cdf90aSEric Fiselier
26677b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
26759cdf90aSEric Fiselier    void swap(array&) _NOEXCEPT {
26859cdf90aSEric Fiselier      static_assert(!is_const<_Tp>::value,
26959cdf90aSEric Fiselier                    "cannot swap zero-sized array of type 'const T'");
27059cdf90aSEric Fiselier    }
27159cdf90aSEric Fiselier
27259cdf90aSEric Fiselier    // iterators:
27377b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
27459cdf90aSEric Fiselier    iterator begin() _NOEXCEPT {return iterator(data());}
27577b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
27659cdf90aSEric Fiselier    const_iterator begin() const _NOEXCEPT {return const_iterator(data());}
27777b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
27859cdf90aSEric Fiselier    iterator end() _NOEXCEPT {return iterator(data());}
27977b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
28059cdf90aSEric Fiselier    const_iterator end() const _NOEXCEPT {return const_iterator(data());}
28159cdf90aSEric Fiselier
28277b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
28359cdf90aSEric Fiselier    reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());}
28477b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
28559cdf90aSEric Fiselier    const_reverse_iterator rbegin() const _NOEXCEPT {return const_reverse_iterator(end());}
28677b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
28759cdf90aSEric Fiselier    reverse_iterator rend() _NOEXCEPT {return reverse_iterator(begin());}
28877b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
28959cdf90aSEric Fiselier    const_reverse_iterator rend() const _NOEXCEPT {return const_reverse_iterator(begin());}
29059cdf90aSEric Fiselier
29177b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
29259cdf90aSEric Fiselier    const_iterator cbegin() const _NOEXCEPT {return begin();}
29377b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
29459cdf90aSEric Fiselier    const_iterator cend() const _NOEXCEPT {return end();}
29577b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
29659cdf90aSEric Fiselier    const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
29777b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
29859cdf90aSEric Fiselier    const_reverse_iterator crend() const _NOEXCEPT {return rend();}
29959cdf90aSEric Fiselier
30059cdf90aSEric Fiselier    // capacity:
30159cdf90aSEric Fiselier    _LIBCPP_INLINE_VISIBILITY
30259cdf90aSEric Fiselier    _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT {return 0; }
30359cdf90aSEric Fiselier    _LIBCPP_INLINE_VISIBILITY
30459cdf90aSEric Fiselier    _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT {return 0;}
30559cdf90aSEric Fiselier    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
30659cdf90aSEric Fiselier    _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return true;}
30759cdf90aSEric Fiselier
30859cdf90aSEric Fiselier    // element access:
30977b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
3105f6a5ac1SMarshall Clow    reference operator[](size_type) _NOEXCEPT {
31159cdf90aSEric Fiselier      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
31259cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
31359cdf90aSEric Fiselier    }
31459cdf90aSEric Fiselier
31559cdf90aSEric Fiselier    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
3165f6a5ac1SMarshall Clow    const_reference operator[](size_type) const _NOEXCEPT {
31759cdf90aSEric Fiselier      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
31859cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
31959cdf90aSEric Fiselier    }
32059cdf90aSEric Fiselier
32177b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
32259cdf90aSEric Fiselier    reference at(size_type) {
32359cdf90aSEric Fiselier      __throw_out_of_range("array<T, 0>::at");
32459cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
32559cdf90aSEric Fiselier    }
32659cdf90aSEric Fiselier
32777b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
32859cdf90aSEric Fiselier    const_reference at(size_type) const {
32959cdf90aSEric Fiselier      __throw_out_of_range("array<T, 0>::at");
33059cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
33159cdf90aSEric Fiselier    }
33259cdf90aSEric Fiselier
33377b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
3349ea0e473SMarshall Clow    reference front() _NOEXCEPT {
33559cdf90aSEric Fiselier      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::front() on a zero-sized array");
33659cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
33759cdf90aSEric Fiselier    }
33859cdf90aSEric Fiselier
33977b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
3409ea0e473SMarshall Clow    const_reference front() const _NOEXCEPT {
34159cdf90aSEric Fiselier      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::front() on a zero-sized array");
34259cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
34359cdf90aSEric Fiselier    }
34459cdf90aSEric Fiselier
34577b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
3469ea0e473SMarshall Clow    reference back() _NOEXCEPT {
34759cdf90aSEric Fiselier      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::back() on a zero-sized array");
34859cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
34959cdf90aSEric Fiselier    }
35059cdf90aSEric Fiselier
35177b9abfcSLouis Dionne    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
3529ea0e473SMarshall Clow    const_reference back() const _NOEXCEPT {
35359cdf90aSEric Fiselier      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::back() on a zero-sized array");
35459cdf90aSEric Fiselier      _LIBCPP_UNREACHABLE();
35559cdf90aSEric Fiselier    }
35659cdf90aSEric Fiselier};
35759cdf90aSEric Fiselier
35859cdf90aSEric Fiselier
35901666904SLouis Dionne#if _LIBCPP_STD_VER >= 17
3600ca8c089SMarshall Clowtemplate<class _Tp, class... _Args,
361*4e0ea2cfSLouis Dionne         class = enable_if_t<__all<_IsSame<_Tp, _Args>::value...>::value>
3620ca8c089SMarshall Clow         >
3630ca8c089SMarshall Clowarray(_Tp, _Args...)
3640ca8c089SMarshall Clow  -> array<_Tp, 1 + sizeof...(_Args)>;
3650ca8c089SMarshall Clow#endif
3660ca8c089SMarshall Clow
3673e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
3683af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
36907d8ac0aSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
3703e519524SHoward Hinnantoperator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
3713e519524SHoward Hinnant{
37259cdf90aSEric Fiselier    return _VSTD::equal(__x.begin(), __x.end(), __y.begin());
3733e519524SHoward Hinnant}
3743e519524SHoward Hinnant
3753e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
3763af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
37707d8ac0aSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
3783e519524SHoward Hinnantoperator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
3793e519524SHoward Hinnant{
3803e519524SHoward Hinnant    return !(__x == __y);
3813e519524SHoward Hinnant}
3823e519524SHoward Hinnant
3833e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
3843af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
38507d8ac0aSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
3863e519524SHoward Hinnantoperator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
3873e519524SHoward Hinnant{
38859cdf90aSEric Fiselier    return _VSTD::lexicographical_compare(__x.begin(), __x.end(),
38959cdf90aSEric Fiselier                                          __y.begin(), __y.end());
3903e519524SHoward Hinnant}
3913e519524SHoward Hinnant
3923e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
3933af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
39407d8ac0aSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
3953e519524SHoward Hinnantoperator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
3963e519524SHoward Hinnant{
3973e519524SHoward Hinnant    return __y < __x;
3983e519524SHoward Hinnant}
3993e519524SHoward Hinnant
4003e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
4013af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
40207d8ac0aSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
4033e519524SHoward Hinnantoperator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
4043e519524SHoward Hinnant{
4053e519524SHoward Hinnant    return !(__y < __x);
4063e519524SHoward Hinnant}
4073e519524SHoward Hinnant
4083e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
4093af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41007d8ac0aSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
4113e519524SHoward Hinnantoperator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
4123e519524SHoward Hinnant{
4133e519524SHoward Hinnant    return !(__x < __y);
4143e519524SHoward Hinnant}
4153e519524SHoward Hinnant
4163e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
41777b9abfcSLouis Dionneinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
418bc95cf0dSHoward Hinnanttypename enable_if
419bc95cf0dSHoward Hinnant<
420f07dd8d0SEric Fiselier    _Size == 0 ||
421bc95cf0dSHoward Hinnant    __is_swappable<_Tp>::value,
4223e519524SHoward Hinnant    void
423bc95cf0dSHoward Hinnant>::type
424ee66eb13SMarshall Clowswap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
425f07dd8d0SEric Fiselier                                  _NOEXCEPT_(noexcept(__x.swap(__y)))
4263e519524SHoward Hinnant{
4273e519524SHoward Hinnant    __x.swap(__y);
4283e519524SHoward Hinnant}
4293e519524SHoward Hinnant
4303e519524SHoward Hinnanttemplate <class _Tp, size_t _Size>
431e4957601SMarshall Clowstruct _LIBCPP_TEMPLATE_VIS tuple_size<array<_Tp, _Size> >
432f5ab703fSHoward Hinnant    : public integral_constant<size_t, _Size> {};
4333e519524SHoward Hinnant
4343e519524SHoward Hinnanttemplate <size_t _Ip, class _Tp, size_t _Size>
4352b0c7abbSLouis Dionnestruct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, array<_Tp, _Size> >
4363e519524SHoward Hinnant{
4376db379a2SMarshall Clow    static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
4383e519524SHoward Hinnant    typedef _Tp type;
4393e519524SHoward Hinnant};
4403e519524SHoward Hinnant
4413e519524SHoward Hinnanttemplate <size_t _Ip, class _Tp, size_t _Size>
4423af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
4433e519524SHoward Hinnant_Tp&
4448f0cd597SHoward Hinnantget(array<_Tp, _Size>& __a) _NOEXCEPT
4453e519524SHoward Hinnant{
44636a60721SMarshall Clow    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
4478bf1f08aSMarshall Clow    return __a.__elems_[_Ip];
4483e519524SHoward Hinnant}
4493e519524SHoward Hinnant
4503e519524SHoward Hinnanttemplate <size_t _Ip, class _Tp, size_t _Size>
4513af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
4523e519524SHoward Hinnantconst _Tp&
4538f0cd597SHoward Hinnantget(const array<_Tp, _Size>& __a) _NOEXCEPT
4543e519524SHoward Hinnant{
45536a60721SMarshall Clow    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
4568bf1f08aSMarshall Clow    return __a.__elems_[_Ip];
4573e519524SHoward Hinnant}
4583e519524SHoward Hinnant
459601afb30SHoward Hinnanttemplate <size_t _Ip, class _Tp, size_t _Size>
4603af48ef7SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
461601afb30SHoward Hinnant_Tp&&
4628f0cd597SHoward Hinnantget(array<_Tp, _Size>&& __a) _NOEXCEPT
463601afb30SHoward Hinnant{
46436a60721SMarshall Clow    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
4658bf1f08aSMarshall Clow    return _VSTD::move(__a.__elems_[_Ip]);
466601afb30SHoward Hinnant}
467601afb30SHoward Hinnant
468545b8861SEric Fiseliertemplate <size_t _Ip, class _Tp, size_t _Size>
469545b8861SEric Fiselierinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
470545b8861SEric Fiselierconst _Tp&&
471545b8861SEric Fiselierget(const array<_Tp, _Size>&& __a) _NOEXCEPT
472545b8861SEric Fiselier{
473545b8861SEric Fiselier    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
474545b8861SEric Fiselier    return _VSTD::move(__a.__elems_[_Ip]);
475545b8861SEric Fiselier}
476545b8861SEric Fiselier
477e93e58c6SMarek Kurdej#if _LIBCPP_STD_VER > 17
478e93e58c6SMarek Kurdej
479e93e58c6SMarek Kurdejtemplate <typename _Tp, size_t _Size, size_t... _Index>
480e93e58c6SMarek Kurdej_LIBCPP_INLINE_VISIBILITY constexpr array<remove_cv_t<_Tp>, _Size>
481e93e58c6SMarek Kurdej__to_array_lvalue_impl(_Tp (&__arr)[_Size], index_sequence<_Index...>) {
482e93e58c6SMarek Kurdej  return {{__arr[_Index]...}};
483e93e58c6SMarek Kurdej}
484e93e58c6SMarek Kurdej
485e93e58c6SMarek Kurdejtemplate <typename _Tp, size_t _Size, size_t... _Index>
486e93e58c6SMarek Kurdej_LIBCPP_INLINE_VISIBILITY constexpr array<remove_cv_t<_Tp>, _Size>
487e93e58c6SMarek Kurdej__to_array_rvalue_impl(_Tp(&&__arr)[_Size], index_sequence<_Index...>) {
488e93e58c6SMarek Kurdej  return {{_VSTD::move(__arr[_Index])...}};
489e93e58c6SMarek Kurdej}
490e93e58c6SMarek Kurdej
491e93e58c6SMarek Kurdejtemplate <typename _Tp, size_t _Size>
492e93e58c6SMarek Kurdej_LIBCPP_INLINE_VISIBILITY constexpr array<remove_cv_t<_Tp>, _Size>
493e93e58c6SMarek Kurdejto_array(_Tp (&__arr)[_Size]) noexcept(is_nothrow_constructible_v<_Tp, _Tp&>) {
494e93e58c6SMarek Kurdej  static_assert(
495e93e58c6SMarek Kurdej      !is_array_v<_Tp>,
496e93e58c6SMarek Kurdej      "[array.creation]/1: to_array does not accept multidimensional arrays.");
497e93e58c6SMarek Kurdej  static_assert(
498e93e58c6SMarek Kurdej      is_constructible_v<_Tp, _Tp&>,
499e93e58c6SMarek Kurdej      "[array.creation]/1: to_array requires copy constructible elements.");
500781c476cSArthur O'Dwyer  return _VSTD::__to_array_lvalue_impl(__arr, make_index_sequence<_Size>());
501e93e58c6SMarek Kurdej}
502e93e58c6SMarek Kurdej
503e93e58c6SMarek Kurdejtemplate <typename _Tp, size_t _Size>
504e93e58c6SMarek Kurdej_LIBCPP_INLINE_VISIBILITY constexpr array<remove_cv_t<_Tp>, _Size>
505e93e58c6SMarek Kurdejto_array(_Tp(&&__arr)[_Size]) noexcept(is_nothrow_move_constructible_v<_Tp>) {
506e93e58c6SMarek Kurdej  static_assert(
507e93e58c6SMarek Kurdej      !is_array_v<_Tp>,
508e93e58c6SMarek Kurdej      "[array.creation]/4: to_array does not accept multidimensional arrays.");
509e93e58c6SMarek Kurdej  static_assert(
510e93e58c6SMarek Kurdej      is_move_constructible_v<_Tp>,
511e93e58c6SMarek Kurdej      "[array.creation]/4: to_array requires move constructible elements.");
512781c476cSArthur O'Dwyer  return _VSTD::__to_array_rvalue_impl(_VSTD::move(__arr),
513e93e58c6SMarek Kurdej                                       make_index_sequence<_Size>());
514e93e58c6SMarek Kurdej}
515e93e58c6SMarek Kurdej
516e93e58c6SMarek Kurdej#endif // _LIBCPP_STD_VER > 17
517e93e58c6SMarek Kurdej
5183e519524SHoward Hinnant_LIBCPP_END_NAMESPACE_STD
5193e519524SHoward Hinnant
5203e519524SHoward Hinnant#endif // _LIBCPP_ARRAY
521