xref: /llvm-project-15.0.7/libcxx/include/array (revision 498ee00a)
1// -*- C++ -*-
2//===---------------------------- array -----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_ARRAY
12#define _LIBCPP_ARRAY
13
14/*
15    array synopsis
16
17namespace std
18{
19template <class T, size_t N >
20struct array
21{
22    // types:
23    typedef T & reference;
24    typedef const T & const_reference;
25    typedef implementation defined iterator;
26    typedef implementation defined const_iterator;
27    typedef size_t size_type;
28    typedef ptrdiff_t difference_type;
29    typedef T value_type;
30    typedef T* pointer;
31    typedef const T* const_pointer;
32    typedef std::reverse_iterator<iterator> reverse_iterator;
33    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
34
35    // No explicit construct/copy/destroy for aggregate type
36    void fill(const T& u);
37    void swap(array& a) noexcept(is_nothrow_swappable_v<T>);
38
39    // iterators:
40    iterator begin() noexcept;
41    const_iterator begin() const noexcept;
42    iterator end() noexcept;
43    const_iterator end() const noexcept;
44
45    reverse_iterator rbegin() noexcept;
46    const_reverse_iterator rbegin() const noexcept;
47    reverse_iterator rend() noexcept;
48    const_reverse_iterator rend() const noexcept;
49
50    const_iterator cbegin() const noexcept;
51    const_iterator cend() const noexcept;
52    const_reverse_iterator crbegin() const noexcept;
53    const_reverse_iterator crend() const noexcept;
54
55    // capacity:
56    constexpr size_type size() const noexcept;
57    constexpr size_type max_size() const noexcept;
58    constexpr bool empty() const noexcept;
59
60    // element access:
61    reference operator[](size_type n);
62    const_reference operator[](size_type n) const; // constexpr in C++14
63    const_reference at(size_type n) const; // constexpr in C++14
64    reference at(size_type n);
65
66    reference front();
67    const_reference front() const; // constexpr in C++14
68    reference back();
69    const_reference back() const; // constexpr in C++14
70
71    T* data() noexcept;
72    const T* data() const noexcept;
73};
74
75template <class T, size_t N>
76  bool operator==(const array<T,N>& x, const array<T,N>& y);
77template <class T, size_t N>
78  bool operator!=(const array<T,N>& x, const array<T,N>& y);
79template <class T, size_t N>
80  bool operator<(const array<T,N>& x, const array<T,N>& y);
81template <class T, size_t N>
82  bool operator>(const array<T,N>& x, const array<T,N>& y);
83template <class T, size_t N>
84  bool operator<=(const array<T,N>& x, const array<T,N>& y);
85template <class T, size_t N>
86  bool operator>=(const array<T,N>& x, const array<T,N>& y);
87
88template <class T, size_t N >
89  void swap(array<T,N>& x, array<T,N>& y) noexcept(noexcept(x.swap(y)));
90
91template <class T> class tuple_size;
92template <size_t I, class T> class tuple_element;
93template <class T, size_t N> struct tuple_size<array<T, N>>;
94template <size_t I, class T, size_t N> struct tuple_element<I, array<T, N>>;
95template <size_t I, class T, size_t N> T& get(array<T, N>&) noexcept; // constexpr in C++14
96template <size_t I, class T, size_t N> const T& get(const array<T, N>&) noexcept; // constexpr in C++14
97template <size_t I, class T, size_t N> T&& get(array<T, N>&&) noexcept; // constexpr in C++14
98template <size_t I, class T, size_t N> const T&& get(const array<T, N>&&) noexcept; // constexpr in C++14
99
100}  // std
101
102*/
103
104#include <__config>
105#include <__tuple>
106#include <type_traits>
107#include <utility>
108#include <iterator>
109#include <algorithm>
110#include <stdexcept>
111
112#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
113#pragma GCC system_header
114#endif
115
116_LIBCPP_BEGIN_NAMESPACE_STD
117
118template <class _Tp, size_t _Size>
119struct _LIBCPP_TYPE_VIS_ONLY array
120{
121    // types:
122    typedef array __self;
123    typedef _Tp                                   value_type;
124    typedef value_type&                           reference;
125    typedef const value_type&                     const_reference;
126    typedef value_type*                           iterator;
127    typedef const value_type*                     const_iterator;
128    typedef value_type*                           pointer;
129    typedef const value_type*                     const_pointer;
130    typedef size_t                                size_type;
131    typedef ptrdiff_t                             difference_type;
132    typedef std::reverse_iterator<iterator>       reverse_iterator;
133    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
134
135    value_type __elems_[_Size > 0 ? _Size : 1];
136
137    // No explicit construct/copy/destroy for aggregate type
138    _LIBCPP_INLINE_VISIBILITY void fill(const value_type& __u)
139        {_VSTD::fill_n(__elems_, _Size, __u);}
140    _LIBCPP_INLINE_VISIBILITY
141    void swap(array& __a) _NOEXCEPT_(_Size == 0 || __is_nothrow_swappable<_Tp>::value)
142        { __swap_dispatch((std::integral_constant<bool, _Size == 0>()), __a); }
143
144    _LIBCPP_INLINE_VISIBILITY
145    void __swap_dispatch(std::true_type, array&) {}
146
147    _LIBCPP_INLINE_VISIBILITY
148    void __swap_dispatch(std::false_type, array& __a)
149        { _VSTD::swap_ranges(__elems_, __elems_ + _Size, __a.__elems_);}
150
151    // iterators:
152    _LIBCPP_INLINE_VISIBILITY
153    iterator begin() _NOEXCEPT {return iterator(__elems_);}
154    _LIBCPP_INLINE_VISIBILITY
155    const_iterator begin() const _NOEXCEPT {return const_iterator(__elems_);}
156    _LIBCPP_INLINE_VISIBILITY
157    iterator end() _NOEXCEPT {return iterator(__elems_ + _Size);}
158    _LIBCPP_INLINE_VISIBILITY
159    const_iterator end() const _NOEXCEPT {return const_iterator(__elems_ + _Size);}
160
161    _LIBCPP_INLINE_VISIBILITY
162    reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());}
163    _LIBCPP_INLINE_VISIBILITY
164    const_reverse_iterator rbegin() const _NOEXCEPT {return const_reverse_iterator(end());}
165    _LIBCPP_INLINE_VISIBILITY
166    reverse_iterator rend() _NOEXCEPT {return reverse_iterator(begin());}
167    _LIBCPP_INLINE_VISIBILITY
168    const_reverse_iterator rend() const _NOEXCEPT {return const_reverse_iterator(begin());}
169
170    _LIBCPP_INLINE_VISIBILITY
171    const_iterator cbegin() const _NOEXCEPT {return begin();}
172    _LIBCPP_INLINE_VISIBILITY
173    const_iterator cend() const _NOEXCEPT {return end();}
174    _LIBCPP_INLINE_VISIBILITY
175    const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
176    _LIBCPP_INLINE_VISIBILITY
177    const_reverse_iterator crend() const _NOEXCEPT {return rend();}
178
179    // capacity:
180    _LIBCPP_INLINE_VISIBILITY
181    _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT {return _Size;}
182    _LIBCPP_INLINE_VISIBILITY
183    _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT {return _Size;}
184    _LIBCPP_INLINE_VISIBILITY
185    _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return _Size == 0;}
186
187    // element access:
188    _LIBCPP_INLINE_VISIBILITY reference operator[](size_type __n)             {return __elems_[__n];}
189    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference operator[](size_type __n) const {return __elems_[__n];}
190    reference at(size_type __n);
191    _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference at(size_type __n) const;
192
193    _LIBCPP_INLINE_VISIBILITY reference front()             {return __elems_[0];}
194    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference front() const {return __elems_[0];}
195    _LIBCPP_INLINE_VISIBILITY reference back()              {return __elems_[_Size > 0 ? _Size-1 : 0];}
196    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference back() const  {return __elems_[_Size > 0 ? _Size-1 : 0];}
197
198    _LIBCPP_INLINE_VISIBILITY
199    value_type* data() _NOEXCEPT {return __elems_;}
200    _LIBCPP_INLINE_VISIBILITY
201    const value_type* data() const _NOEXCEPT {return __elems_;}
202};
203
204template <class _Tp, size_t _Size>
205typename array<_Tp, _Size>::reference
206array<_Tp, _Size>::at(size_type __n)
207{
208    if (__n >= _Size)
209        __throw_out_of_range("array::at");
210
211    return __elems_[__n];
212}
213
214template <class _Tp, size_t _Size>
215_LIBCPP_CONSTEXPR_AFTER_CXX11
216typename array<_Tp, _Size>::const_reference
217array<_Tp, _Size>::at(size_type __n) const
218{
219    if (__n >= _Size)
220        __throw_out_of_range("array::at");
221    return __elems_[__n];
222}
223
224template <class _Tp, size_t _Size>
225inline _LIBCPP_INLINE_VISIBILITY
226bool
227operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
228{
229    return _VSTD::equal(__x.__elems_, __x.__elems_ + _Size, __y.__elems_);
230}
231
232template <class _Tp, size_t _Size>
233inline _LIBCPP_INLINE_VISIBILITY
234bool
235operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
236{
237    return !(__x == __y);
238}
239
240template <class _Tp, size_t _Size>
241inline _LIBCPP_INLINE_VISIBILITY
242bool
243operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
244{
245    return _VSTD::lexicographical_compare(__x.__elems_, __x.__elems_ + _Size, __y.__elems_, __y.__elems_ + _Size);
246}
247
248template <class _Tp, size_t _Size>
249inline _LIBCPP_INLINE_VISIBILITY
250bool
251operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
252{
253    return __y < __x;
254}
255
256template <class _Tp, size_t _Size>
257inline _LIBCPP_INLINE_VISIBILITY
258bool
259operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
260{
261    return !(__y < __x);
262}
263
264template <class _Tp, size_t _Size>
265inline _LIBCPP_INLINE_VISIBILITY
266bool
267operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
268{
269    return !(__x < __y);
270}
271
272template <class _Tp, size_t _Size>
273inline _LIBCPP_INLINE_VISIBILITY
274typename enable_if
275<
276    _Size == 0 ||
277    __is_swappable<_Tp>::value,
278    void
279>::type
280swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
281                                  _NOEXCEPT_(noexcept(__x.swap(__y)))
282{
283    __x.swap(__y);
284}
285
286template <class _Tp, size_t _Size>
287class _LIBCPP_TYPE_VIS_ONLY tuple_size<array<_Tp, _Size> >
288    : public integral_constant<size_t, _Size> {};
289
290template <size_t _Ip, class _Tp, size_t _Size>
291class _LIBCPP_TYPE_VIS_ONLY tuple_element<_Ip, array<_Tp, _Size> >
292{
293public:
294    typedef _Tp type;
295};
296
297template <size_t _Ip, class _Tp, size_t _Size>
298inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
299_Tp&
300get(array<_Tp, _Size>& __a) _NOEXCEPT
301{
302    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
303    return __a.__elems_[_Ip];
304}
305
306template <size_t _Ip, class _Tp, size_t _Size>
307inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
308const _Tp&
309get(const array<_Tp, _Size>& __a) _NOEXCEPT
310{
311    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
312    return __a.__elems_[_Ip];
313}
314
315#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
316
317template <size_t _Ip, class _Tp, size_t _Size>
318inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
319_Tp&&
320get(array<_Tp, _Size>&& __a) _NOEXCEPT
321{
322    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
323    return _VSTD::move(__a.__elems_[_Ip]);
324}
325
326template <size_t _Ip, class _Tp, size_t _Size>
327inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
328const _Tp&&
329get(const array<_Tp, _Size>&& __a) _NOEXCEPT
330{
331    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
332    return _VSTD::move(__a.__elems_[_Ip]);
333}
334
335#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
336
337_LIBCPP_END_NAMESPACE_STD
338
339#endif  // _LIBCPP_ARRAY
340