1// <array> -*- C++ -*- 
2 
3// Copyright (C) 2007-2019 Free Software Foundation, Inc. 
4// 
5// This file is part of the GNU ISO C++ Library. This library is free 
6// software; you can redistribute it and/or modify it under the 
7// terms of the GNU General Public License as published by the 
8// Free Software Foundation; either version 3, or (at your option) 
9// any later version. 
10 
11// This library is distributed in the hope that it will be useful, 
12// but WITHOUT ANY WARRANTY; without even the implied warranty of 
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
14// GNU General Public License for more details. 
15 
16// Under Section 7 of GPL version 3, you are granted additional 
17// permissions described in the GCC Runtime Library Exception, version 
18// 3.1, as published by the Free Software Foundation. 
19 
20// You should have received a copy of the GNU General Public License and 
21// a copy of the GCC Runtime Library Exception along with this program; 
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 
23// <http://www.gnu.org/licenses/>. 
24 
25/** @file include/array 
26 * This is a Standard C++ Library header. 
27 */ 
28 
29#ifndef _GLIBCXX_ARRAY 
30#define _GLIBCXX_ARRAY 1 
31 
32#pragma GCC system_header 
33 
34#if __cplusplus < 201103L 
35# include <bits/c++0x_warning.h> 
36#else 
37 
38#include <utility> 
39#include <stdexcept> 
40#include <bits/stl_algobase.h> 
41#include <bits/range_access.h> 
42 
43namespace std _GLIBCXX_VISIBILITY(default) 
44{ 
45_GLIBCXX_BEGIN_NAMESPACE_CONTAINER 
46 
47 template<typename _Tp, std::size_t _Nm> 
48 struct __array_traits 
49 { 
50 typedef _Tp _Type[_Nm]; 
51 typedef __is_swappable<_Tp> _Is_swappable; 
52 typedef __is_nothrow_swappable<_Tp> _Is_nothrow_swappable; 
53 
54 static constexpr _Tp& 
55 _S_ref(const _Type& __t, std::size_t __n) noexcept 
56 { return const_cast<_Tp&>(__t[__n]); } 
57 
58 static constexpr _Tp* 
59 _S_ptr(const _Type& __t) noexcept 
60 { return const_cast<_Tp*>(__t); } 
61 }; 
62 
63 template<typename _Tp> 
64 struct __array_traits<_Tp, 0> 
65 { 
66 struct _Type { }; 
67 typedef true_type _Is_swappable; 
68 typedef true_type _Is_nothrow_swappable; 
69 
70 static constexpr _Tp& 
71 _S_ref(const _Type&, std::size_t) noexcept 
72 { return *static_cast<_Tp*>(nullptr); } 
73 
74 static constexpr _Tp* 
75 _S_ptr(const _Type&) noexcept 
76 { return nullptr; } 
77 }; 
78 
79 /** 
80 * @brief A standard container for storing a fixed size sequence of elements. 
81 * 
82 * @ingroup sequences 
83 * 
84 * Meets the requirements of a <a href="tables.html#65">container</a>, a 
85 * <a href="tables.html#66">reversible container</a>, and a 
86 * <a href="tables.html#67">sequence</a>. 
87 * 
88 * Sets support random access iterators. 
89 * 
90 * @tparam Tp Type of element. Required to be a complete type. 
91 * @tparam N Number of elements. 
92 */ 
93 template<typename _Tp, std::size_t _Nm> 
94 struct array 
95 { 
96 typedef _Tp value_type; 
97 typedef value_type* pointer; 
98 typedef const value_type* const_pointer; 
99 typedef value_type& reference; 
100 typedef const value_type& const_reference; 
101 typedef value_type* iterator; 
102 typedef const value_type* const_iterator; 
103 typedef std::size_t size_type; 
104 typedef std::ptrdiff_t difference_type; 
105 typedef std::reverse_iterator<iterator> reverse_iterator; 
106 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 
107 
108 // Support for zero-sized arrays mandatory. 
109 typedef _GLIBCXX_STD_C::__array_traits<_Tp, _Nm> _AT_Type; 
110 typename _AT_Type::_Type _M_elems; 
111 
112 // No explicit construct/copy/destroy for aggregate type. 
113 
114 // DR 776. 
115 void 
116 fill(const value_type& __u) 
117 { std::fill_n(begin(), size(), __u); } 
118 
119 void 
120 swap(array& __other) 
121 noexcept(_AT_Type::_Is_nothrow_swappable::value) 
122 { std::swap_ranges(begin(), end(), __other.begin()); } 
123 
124 // Iterators. 
125 _GLIBCXX17_CONSTEXPR iterator 
126 begin() noexcept 
127 { return iterator(data()); } 
128 
129 _GLIBCXX17_CONSTEXPR const_iterator 
130 begin() const noexcept 
131 { return const_iterator(data()); } 
132 
133 _GLIBCXX17_CONSTEXPR iterator 
134 end() noexcept 
135 { return iterator(data() + _Nm); } 
136 
137 _GLIBCXX17_CONSTEXPR const_iterator 
138 end() const noexcept 
139 { return const_iterator(data() + _Nm); } 
140 
141 _GLIBCXX17_CONSTEXPR reverse_iterator 
142 rbegin() noexcept 
143 { return reverse_iterator(end()); } 
144 
145 _GLIBCXX17_CONSTEXPR const_reverse_iterator 
146 rbegin() const noexcept 
147 { return const_reverse_iterator(end()); } 
148 
149 _GLIBCXX17_CONSTEXPR reverse_iterator 
150 rend() noexcept 
151 { return reverse_iterator(begin()); } 
152 
153 _GLIBCXX17_CONSTEXPR const_reverse_iterator 
154 rend() const noexcept 
155 { return const_reverse_iterator(begin()); } 
156 
157 _GLIBCXX17_CONSTEXPR const_iterator 
158 cbegin() const noexcept 
159 { return const_iterator(data()); } 
160 
161 _GLIBCXX17_CONSTEXPR const_iterator 
162 cend() const noexcept 
163 { return const_iterator(data() + _Nm); } 
164 
165 _GLIBCXX17_CONSTEXPR const_reverse_iterator 
166 crbegin() const noexcept 
167 { return const_reverse_iterator(end()); } 
168 
169 _GLIBCXX17_CONSTEXPR const_reverse_iterator 
170 crend() const noexcept 
171 { return const_reverse_iterator(begin()); } 
172 
173 // Capacity. 
174 constexpr size_type 
175 size() const noexcept { return _Nm; } 
176 
177 constexpr size_type 
178 max_size() const noexcept { return _Nm; } 
179 
180 _GLIBCXX_NODISCARD constexpr bool 
181 empty() const noexcept { return size() == 0; } 
182 
183 // Element access. 
184 _GLIBCXX17_CONSTEXPR reference 
185 operator[](size_type __n) noexcept 
186 { return _AT_Type::_S_ref(_M_elems, __n); } 
187 
188 constexpr const_reference 
189 operator[](size_type __n) const noexcept 
190 { return _AT_Type::_S_ref(_M_elems, __n); } 
191 
192 _GLIBCXX17_CONSTEXPR reference 
193 at(size_type __n) 
194 { 
195 if (__n >= _Nm) 
196 std::__throw_out_of_range_fmt(__N("array::at: __n (which is %zu) " 
197 ">= _Nm (which is %zu)"), 
198 __n, _Nm); 
199 return _AT_Type::_S_ref(_M_elems, __n); 
200 } 
201 
202 constexpr const_reference 
203 at(size_type __n) const 
204 { 
205 // Result of conditional expression must be an lvalue so use 
206 // boolean ? lvalue : (throw-expr, lvalue) 
207 return __n < _Nm ? _AT_Type::_S_ref(_M_elems, __n) 
208 : (std::__throw_out_of_range_fmt(__N("array::at: __n (which is %zu) " 
209 ">= _Nm (which is %zu)"), 
210 __n, _Nm), 
211 _AT_Type::_S_ref(_M_elems, 0)); 
212 } 
213 
214 _GLIBCXX17_CONSTEXPR reference 
215 front() noexcept 
216 { return *begin(); } 
217 
218 constexpr const_reference 
219 front() const noexcept 
220 { return _AT_Type::_S_ref(_M_elems, 0); } 
221 
222 _GLIBCXX17_CONSTEXPR reference 
223 back() noexcept 
224 { return _Nm ? *(end() - 1) : *end(); } 
225 
226 constexpr const_reference 
227 back() const noexcept 
228 { 
229 return _Nm ? _AT_Type::_S_ref(_M_elems, _Nm - 1) 
230 : _AT_Type::_S_ref(_M_elems, 0); 
231 } 
232 
233 _GLIBCXX17_CONSTEXPR pointer 
234 data() noexcept 
235 { return _AT_Type::_S_ptr(_M_elems); } 
236 
237 _GLIBCXX17_CONSTEXPR const_pointer 
238 data() const noexcept 
239 { return _AT_Type::_S_ptr(_M_elems); } 
240 }; 
241 
242#if __cpp_deduction_guides >= 201606 
243 template<typename _Tp, typename... _Up> 
244 array(_Tp, _Up...) 
245 -> array<enable_if_t<(is_same_v<_Tp, _Up> && ...), _Tp>, 
246 1 + sizeof...(_Up)>; 
247#endif 
248 
249 // Array comparisons. 
250 template<typename _Tp, std::size_t _Nm> 
251 inline bool 
252 operator==(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two) 
253 { return std::equal(__one.begin(), __one.end(), __two.begin()); } 
254 
255 template<typename _Tp, std::size_t _Nm> 
256 inline bool 
257 operator!=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two) 
258 { return !(__one == __two); } 
259 
260 template<typename _Tp, std::size_t _Nm> 
261 inline bool 
262 operator<(const array<_Tp, _Nm>& __a, const array<_Tp, _Nm>& __b) 
263 { 
264 return std::lexicographical_compare(__a.begin(), __a.end(), 
265 __b.begin(), __b.end()); 
266 } 
267 
268 template<typename _Tp, std::size_t _Nm> 
269 inline bool 
270 operator>(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two) 
271 { return __two < __one; } 
272 
273 template<typename _Tp, std::size_t _Nm> 
274 inline bool 
275 operator<=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two) 
276 { return !(__one > __two); } 
277 
278 template<typename _Tp, std::size_t _Nm> 
279 inline bool 
280 operator>=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two) 
281 { return !(__one < __two); } 
282 
283 // Specialized algorithms. 
284 template<typename _Tp, std::size_t _Nm> 
285 inline 
286#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11 
287 // Constrained free swap overload, see p0185r1 
288 typename enable_if< 
289 _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::_Is_swappable::value 
290 >::type 
291#else 
292 void 
293#endif 
294 swap(array<_Tp, _Nm>& __one, array<_Tp, _Nm>& __two) 
295 noexcept(noexcept(__one.swap(__two))) 
296 { __one.swap(__two); } 
297 
298#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11 
299 template<typename _Tp, std::size_t _Nm> 
300 typename enable_if< 
301 !_GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::_Is_swappable::value>::type 
302 swap(array<_Tp, _Nm>&, array<_Tp, _Nm>&) = delete; 
303#endif 
304 
305 template<std::size_t _Int, typename _Tp, std::size_t _Nm> 
306 constexpr _Tp& 
307 get(array<_Tp, _Nm>& __arr) noexcept 
308 { 
309 static_assert(_Int < _Nm, "array index is within bounds"); 
310 return _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>:: 
311 _S_ref(__arr._M_elems, _Int); 
312 } 
313 
314 template<std::size_t _Int, typename _Tp, std::size_t _Nm> 
315 constexpr _Tp&& 
316 get(array<_Tp, _Nm>&& __arr) noexcept 
317 { 
318 static_assert(_Int < _Nm, "array index is within bounds"); 
319 return std::move(_GLIBCXX_STD_C::get<_Int>(__arr)); 
320 } 
321 
322 template<std::size_t _Int, typename _Tp, std::size_t _Nm> 
323 constexpr const _Tp& 
324 get(const array<_Tp, _Nm>& __arr) noexcept 
325 { 
326 static_assert(_Int < _Nm, "array index is within bounds"); 
327 return _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>:: 
328 _S_ref(__arr._M_elems, _Int); 
329 } 
330 
331 template<std::size_t _Int, typename _Tp, std::size_t _Nm> 
332 constexpr const _Tp&& 
333 get(const array<_Tp, _Nm>&& __arr) noexcept 
334 { 
335 static_assert(_Int < _Nm, "array index is within bounds"); 
336 return std::move(_GLIBCXX_STD_C::get<_Int>(__arr)); 
337 } 
338 
339_GLIBCXX_END_NAMESPACE_CONTAINER 
340} // namespace std 
341 
342namespace std _GLIBCXX_VISIBILITY(default) 
343{ 
344_GLIBCXX_BEGIN_NAMESPACE_VERSION 
345 
346 // Tuple interface to class template array. 
347 
348 /// tuple_size 
349 template<typename _Tp> 
350 struct tuple_size; 
351 
352 /// Partial specialization for std::array 
353 template<typename _Tp, std::size_t _Nm> 
354 struct tuple_size<_GLIBCXX_STD_C::array<_Tp, _Nm>> 
355 : public integral_constant<std::size_t, _Nm> { }; 
356 
357 /// tuple_element 
358 template<std::size_t _Int, typename _Tp> 
359 struct tuple_element; 
360 
361 /// Partial specialization for std::array 
362 template<std::size_t _Int, typename _Tp, std::size_t _Nm> 
363 struct tuple_element<_Int, _GLIBCXX_STD_C::array<_Tp, _Nm>> 
364 { 
365 static_assert(_Int < _Nm, "index is out of bounds"); 
366 typedef _Tp type; 
367 }; 
368 
369 template<typename _Tp, std::size_t _Nm> 
370 struct __is_tuple_like_impl<_GLIBCXX_STD_C::array<_Tp, _Nm>> : true_type 
371 { }; 
372 
373_GLIBCXX_END_NAMESPACE_VERSION 
374} // namespace std 
375 
376#ifdef _GLIBCXX_DEBUG 
377# include <debug/array> 
378#endif 
379 
380#ifdef _GLIBCXX_PROFILE 
381# include <profile/array> 
382#endif 
383 
384#endif // C++11 
385 
386#endif // _GLIBCXX_ARRAY 
387