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#include <cstdlib> // for _LIBCPP_UNREACHABLE
112#include <__debug>
113
114#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
115#pragma GCC system_header
116#endif
117
118
119
120_LIBCPP_BEGIN_NAMESPACE_STD
121
122
123template <class _Tp, size_t _Size>
124struct _LIBCPP_TEMPLATE_VIS array
125{
126    // types:
127    typedef array __self;
128    typedef _Tp                                   value_type;
129    typedef value_type&                           reference;
130    typedef const value_type&                     const_reference;
131    typedef value_type*                           iterator;
132    typedef const value_type*                     const_iterator;
133    typedef value_type*                           pointer;
134    typedef const value_type*                     const_pointer;
135    typedef size_t                                size_type;
136    typedef ptrdiff_t                             difference_type;
137    typedef std::reverse_iterator<iterator>       reverse_iterator;
138    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
139
140    _Tp __elems_[_Size];
141
142    // No explicit construct/copy/destroy for aggregate type
143    _LIBCPP_INLINE_VISIBILITY void fill(const value_type& __u) {
144      _VSTD::fill_n(__elems_, _Size, __u);
145    }
146
147    _LIBCPP_INLINE_VISIBILITY
148    void swap(array& __a) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) {
149      std::swap_ranges(__elems_, __elems_ + _Size, __a.__elems_);
150    }
151
152    // iterators:
153    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
154    iterator begin() _NOEXCEPT {return iterator(data());}
155    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
156    const_iterator begin() const _NOEXCEPT {return const_iterator(data());}
157    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
158    iterator end() _NOEXCEPT {return iterator(data() + _Size);}
159    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
160    const_iterator end() const _NOEXCEPT {return const_iterator(data() + _Size);}
161
162    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
163    reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());}
164    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
165    const_reverse_iterator rbegin() const _NOEXCEPT {return const_reverse_iterator(end());}
166    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
167    reverse_iterator rend() _NOEXCEPT {return reverse_iterator(begin());}
168    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
169    const_reverse_iterator rend() const _NOEXCEPT {return const_reverse_iterator(begin());}
170
171    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
172    const_iterator cbegin() const _NOEXCEPT {return begin();}
173    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
174    const_iterator cend() const _NOEXCEPT {return end();}
175    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
176    const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
177    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
178    const_reverse_iterator crend() const _NOEXCEPT {return rend();}
179
180    // capacity:
181    _LIBCPP_INLINE_VISIBILITY
182    _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT {return _Size;}
183    _LIBCPP_INLINE_VISIBILITY
184    _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT {return _Size;}
185    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
186    _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return false; }
187
188    // element access:
189    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
190    reference operator[](size_type __n)             {return __elems_[__n];}
191    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
192    const_reference operator[](size_type __n) const {return __elems_[__n];}
193
194    _LIBCPP_CONSTEXPR_AFTER_CXX14       reference at(size_type __n);
195    _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference at(size_type __n) const;
196
197    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference front()             {return __elems_[0];}
198    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference front() const {return __elems_[0];}
199    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference back()              {return __elems_[_Size - 1];}
200    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 const_reference back() const  {return __elems_[_Size - 1];}
201
202    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
203    value_type* data() _NOEXCEPT {return __elems_;}
204    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
205    const value_type* data() const _NOEXCEPT {return __elems_;}
206};
207
208
209template <class _Tp, size_t _Size>
210_LIBCPP_CONSTEXPR_AFTER_CXX14
211typename array<_Tp, _Size>::reference
212array<_Tp, _Size>::at(size_type __n)
213{
214    if (__n >= _Size)
215        __throw_out_of_range("array::at");
216
217    return __elems_[__n];
218}
219
220template <class _Tp, size_t _Size>
221_LIBCPP_CONSTEXPR_AFTER_CXX11
222typename array<_Tp, _Size>::const_reference
223array<_Tp, _Size>::at(size_type __n) const
224{
225    if (__n >= _Size)
226        __throw_out_of_range("array::at");
227    return __elems_[__n];
228}
229
230template <class _Tp>
231struct _LIBCPP_TEMPLATE_VIS array<_Tp, 0>
232{
233    // types:
234    typedef array __self;
235    typedef _Tp                                   value_type;
236    typedef value_type&                           reference;
237    typedef const value_type&                     const_reference;
238    typedef value_type*                           iterator;
239    typedef const value_type*                     const_iterator;
240    typedef value_type*                           pointer;
241    typedef const value_type*                     const_pointer;
242    typedef size_t                                size_type;
243    typedef ptrdiff_t                             difference_type;
244    typedef std::reverse_iterator<iterator>       reverse_iterator;
245    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
246
247
248    typedef typename conditional<is_const<_Tp>::value, const char,
249                                char>::type _CharType;
250    _ALIGNAS(alignment_of<_Tp[1]>::value) _CharType __elems_[sizeof(_Tp[1])];
251
252    // No explicit construct/copy/destroy for aggregate type
253    _LIBCPP_INLINE_VISIBILITY void fill(const value_type&) {
254      static_assert(!is_const<_Tp>::value,
255                    "cannot fill zero-sized array of type 'const T'");
256    }
257
258    _LIBCPP_INLINE_VISIBILITY
259    void swap(array&) _NOEXCEPT {
260      static_assert(!is_const<_Tp>::value,
261                    "cannot swap zero-sized array of type 'const T'");
262    }
263
264    // iterators:
265    _LIBCPP_INLINE_VISIBILITY
266    iterator begin() _NOEXCEPT {return iterator(data());}
267    _LIBCPP_INLINE_VISIBILITY
268    const_iterator begin() const _NOEXCEPT {return const_iterator(data());}
269    _LIBCPP_INLINE_VISIBILITY
270    iterator end() _NOEXCEPT {return iterator(data());}
271    _LIBCPP_INLINE_VISIBILITY
272    const_iterator end() const _NOEXCEPT {return const_iterator(data());}
273
274    _LIBCPP_INLINE_VISIBILITY
275    reverse_iterator rbegin() _NOEXCEPT {return reverse_iterator(end());}
276    _LIBCPP_INLINE_VISIBILITY
277    const_reverse_iterator rbegin() const _NOEXCEPT {return const_reverse_iterator(end());}
278    _LIBCPP_INLINE_VISIBILITY
279    reverse_iterator rend() _NOEXCEPT {return reverse_iterator(begin());}
280    _LIBCPP_INLINE_VISIBILITY
281    const_reverse_iterator rend() const _NOEXCEPT {return const_reverse_iterator(begin());}
282
283    _LIBCPP_INLINE_VISIBILITY
284    const_iterator cbegin() const _NOEXCEPT {return begin();}
285    _LIBCPP_INLINE_VISIBILITY
286    const_iterator cend() const _NOEXCEPT {return end();}
287    _LIBCPP_INLINE_VISIBILITY
288    const_reverse_iterator crbegin() const _NOEXCEPT {return rbegin();}
289    _LIBCPP_INLINE_VISIBILITY
290    const_reverse_iterator crend() const _NOEXCEPT {return rend();}
291
292    // capacity:
293    _LIBCPP_INLINE_VISIBILITY
294    _LIBCPP_CONSTEXPR size_type size() const _NOEXCEPT {return 0; }
295    _LIBCPP_INLINE_VISIBILITY
296    _LIBCPP_CONSTEXPR size_type max_size() const _NOEXCEPT {return 0;}
297    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
298    _LIBCPP_CONSTEXPR bool empty() const _NOEXCEPT {return true;}
299
300    // element access:
301    _LIBCPP_INLINE_VISIBILITY
302    reference operator[](size_type) {
303      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
304      _LIBCPP_UNREACHABLE();
305    }
306
307    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
308    const_reference operator[](size_type) const {
309      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::operator[] on a zero-sized array");
310      _LIBCPP_UNREACHABLE();
311    }
312
313    _LIBCPP_INLINE_VISIBILITY
314    reference at(size_type) {
315      __throw_out_of_range("array<T, 0>::at");
316      _LIBCPP_UNREACHABLE();
317    }
318
319    _LIBCPP_INLINE_VISIBILITY
320    const_reference at(size_type) const {
321      __throw_out_of_range("array<T, 0>::at");
322      _LIBCPP_UNREACHABLE();
323    }
324
325    _LIBCPP_INLINE_VISIBILITY
326    reference front() {
327      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::front() on a zero-sized array");
328      _LIBCPP_UNREACHABLE();
329    }
330
331    _LIBCPP_INLINE_VISIBILITY
332    const_reference front() const {
333      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::front() on a zero-sized array");
334      _LIBCPP_UNREACHABLE();
335    }
336
337    _LIBCPP_INLINE_VISIBILITY
338    reference back() {
339      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::back() on a zero-sized array");
340      _LIBCPP_UNREACHABLE();
341    }
342
343    _LIBCPP_INLINE_VISIBILITY
344    const_reference back() const {
345      _LIBCPP_ASSERT(false, "cannot call array<T, 0>::back() on a zero-sized array");
346      _LIBCPP_UNREACHABLE();
347    }
348
349    _LIBCPP_INLINE_VISIBILITY
350    value_type* data() _NOEXCEPT {return reinterpret_cast<value_type*>(__elems_);}
351    _LIBCPP_INLINE_VISIBILITY
352    const value_type* data() const _NOEXCEPT {return reinterpret_cast<const value_type*>(__elems_);}
353};
354
355
356template <class _Tp, size_t _Size>
357inline _LIBCPP_INLINE_VISIBILITY
358bool
359operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
360{
361    return _VSTD::equal(__x.begin(), __x.end(), __y.begin());
362}
363
364template <class _Tp, size_t _Size>
365inline _LIBCPP_INLINE_VISIBILITY
366bool
367operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
368{
369    return !(__x == __y);
370}
371
372template <class _Tp, size_t _Size>
373inline _LIBCPP_INLINE_VISIBILITY
374bool
375operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
376{
377    return _VSTD::lexicographical_compare(__x.begin(), __x.end(),
378                                          __y.begin(), __y.end());
379}
380
381template <class _Tp, size_t _Size>
382inline _LIBCPP_INLINE_VISIBILITY
383bool
384operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
385{
386    return __y < __x;
387}
388
389template <class _Tp, size_t _Size>
390inline _LIBCPP_INLINE_VISIBILITY
391bool
392operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
393{
394    return !(__y < __x);
395}
396
397template <class _Tp, size_t _Size>
398inline _LIBCPP_INLINE_VISIBILITY
399bool
400operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
401{
402    return !(__x < __y);
403}
404
405template <class _Tp, size_t _Size>
406inline _LIBCPP_INLINE_VISIBILITY
407typename enable_if
408<
409    _Size == 0 ||
410    __is_swappable<_Tp>::value,
411    void
412>::type
413swap(array<_Tp, _Size>& __x, array<_Tp, _Size>& __y)
414                                  _NOEXCEPT_(noexcept(__x.swap(__y)))
415{
416    __x.swap(__y);
417}
418
419template <class _Tp, size_t _Size>
420class _LIBCPP_TEMPLATE_VIS tuple_size<array<_Tp, _Size> >
421    : public integral_constant<size_t, _Size> {};
422
423template <size_t _Ip, class _Tp, size_t _Size>
424class _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, array<_Tp, _Size> >
425{
426    static_assert(_Ip < _Size, "Index out of bounds in std::tuple_element<> (std::array)");
427public:
428    typedef _Tp type;
429};
430
431template <size_t _Ip, class _Tp, size_t _Size>
432inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
433_Tp&
434get(array<_Tp, _Size>& __a) _NOEXCEPT
435{
436    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array)");
437    return __a.__elems_[_Ip];
438}
439
440template <size_t _Ip, class _Tp, size_t _Size>
441inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
442const _Tp&
443get(const array<_Tp, _Size>& __a) _NOEXCEPT
444{
445    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array)");
446    return __a.__elems_[_Ip];
447}
448
449#ifndef _LIBCPP_CXX03_LANG
450
451template <size_t _Ip, class _Tp, size_t _Size>
452inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
453_Tp&&
454get(array<_Tp, _Size>&& __a) _NOEXCEPT
455{
456    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (std::array &&)");
457    return _VSTD::move(__a.__elems_[_Ip]);
458}
459
460template <size_t _Ip, class _Tp, size_t _Size>
461inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
462const _Tp&&
463get(const array<_Tp, _Size>&& __a) _NOEXCEPT
464{
465    static_assert(_Ip < _Size, "Index out of bounds in std::get<> (const std::array &&)");
466    return _VSTD::move(__a.__elems_[_Ip]);
467}
468
469#endif  // !_LIBCPP_CXX03_LANG
470
471_LIBCPP_END_NAMESPACE_STD
472
473#endif  // _LIBCPP_ARRAY
474