1// <array> -*- C++ -*-
2
3// Copyright (C) 2007-2016 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
52      static constexpr _Tp&
53      _S_ref(const _Type& __t, std::size_t __n) noexcept
54      { return const_cast<_Tp&>(__t[__n]); }
55
56      static constexpr _Tp*
57      _S_ptr(const _Type& __t) noexcept
58      { return const_cast<_Tp*>(__t); }
59    };
60
61 template<typename _Tp>
62   struct __array_traits<_Tp, 0>
63   {
64     struct _Type { };
65
66     static constexpr _Tp&
67     _S_ref(const _Type&, std::size_t) noexcept
68     { return *static_cast<_Tp*>(nullptr); }
69
70     static constexpr _Tp*
71     _S_ptr(const _Type&) noexcept
72     { return nullptr; }
73   };
74
75  /**
76   *  @brief A standard container for storing a fixed size sequence of elements.
77   *
78   *  @ingroup sequences
79   *
80   *  Meets the requirements of a <a href="tables.html#65">container</a>, a
81   *  <a href="tables.html#66">reversible container</a>, and a
82   *  <a href="tables.html#67">sequence</a>.
83   *
84   *  Sets support random access iterators.
85   *
86   *  @tparam  Tp  Type of element. Required to be a complete type.
87   *  @tparam  N  Number of elements.
88  */
89  template<typename _Tp, std::size_t _Nm>
90    struct array
91    {
92      typedef _Tp 	    			      value_type;
93      typedef value_type*			      pointer;
94      typedef const value_type*                       const_pointer;
95      typedef value_type&                   	      reference;
96      typedef const value_type&             	      const_reference;
97      typedef value_type*          		      iterator;
98      typedef const value_type*			      const_iterator;
99      typedef std::size_t                    	      size_type;
100      typedef std::ptrdiff_t                   	      difference_type;
101      typedef std::reverse_iterator<iterator>	      reverse_iterator;
102      typedef std::reverse_iterator<const_iterator>   const_reverse_iterator;
103
104      // Support for zero-sized arrays mandatory.
105      typedef _GLIBCXX_STD_C::__array_traits<_Tp, _Nm> _AT_Type;
106      typename _AT_Type::_Type                         _M_elems;
107
108      // No explicit construct/copy/destroy for aggregate type.
109
110      // DR 776.
111      void
112      fill(const value_type& __u)
113      { std::fill_n(begin(), size(), __u); }
114
115      void
116      swap(array& __other)
117      noexcept(__is_nothrow_swappable<_Tp>::value)
118      { std::swap_ranges(begin(), end(), __other.begin()); }
119
120      // Iterators.
121      iterator
122      begin() noexcept
123      { return iterator(data()); }
124
125      const_iterator
126      begin() const noexcept
127      { return const_iterator(data()); }
128
129      iterator
130      end() noexcept
131      { return iterator(data() + _Nm); }
132
133      const_iterator
134      end() const noexcept
135      { return const_iterator(data() + _Nm); }
136
137      reverse_iterator
138      rbegin() noexcept
139      { return reverse_iterator(end()); }
140
141      const_reverse_iterator
142      rbegin() const noexcept
143      { return const_reverse_iterator(end()); }
144
145      reverse_iterator
146      rend() noexcept
147      { return reverse_iterator(begin()); }
148
149      const_reverse_iterator
150      rend() const noexcept
151      { return const_reverse_iterator(begin()); }
152
153      const_iterator
154      cbegin() const noexcept
155      { return const_iterator(data()); }
156
157      const_iterator
158      cend() const noexcept
159      { return const_iterator(data() + _Nm); }
160
161      const_reverse_iterator
162      crbegin() const noexcept
163      { return const_reverse_iterator(end()); }
164
165      const_reverse_iterator
166      crend() const noexcept
167      { return const_reverse_iterator(begin()); }
168
169      // Capacity.
170      constexpr size_type
171      size() const noexcept { return _Nm; }
172
173      constexpr size_type
174      max_size() const noexcept { return _Nm; }
175
176      constexpr bool
177      empty() const noexcept { return size() == 0; }
178
179      // Element access.
180      reference
181      operator[](size_type __n) noexcept
182      { return _AT_Type::_S_ref(_M_elems, __n); }
183
184      constexpr const_reference
185      operator[](size_type __n) const noexcept
186      { return _AT_Type::_S_ref(_M_elems, __n); }
187
188      reference
189      at(size_type __n)
190      {
191	if (__n >= _Nm)
192	  std::__throw_out_of_range_fmt(__N("array::at: __n (which is %zu) "
193					    ">= _Nm (which is %zu)"),
194					__n, _Nm);
195	return _AT_Type::_S_ref(_M_elems, __n);
196      }
197
198      constexpr const_reference
199      at(size_type __n) const
200      {
201	// Result of conditional expression must be an lvalue so use
202	// boolean ? lvalue : (throw-expr, lvalue)
203	return __n < _Nm ? _AT_Type::_S_ref(_M_elems, __n)
204	  : (std::__throw_out_of_range_fmt(__N("array::at: __n (which is %zu) "
205					       ">= _Nm (which is %zu)"),
206					   __n, _Nm),
207	     _AT_Type::_S_ref(_M_elems, 0));
208      }
209
210      reference
211      front() noexcept
212      { return *begin(); }
213
214      constexpr const_reference
215      front() const noexcept
216      { return _AT_Type::_S_ref(_M_elems, 0); }
217
218      reference
219      back() noexcept
220      { return _Nm ? *(end() - 1) : *end(); }
221
222      constexpr const_reference
223      back() const noexcept
224      {
225	return _Nm ? _AT_Type::_S_ref(_M_elems, _Nm - 1)
226 	           : _AT_Type::_S_ref(_M_elems, 0);
227      }
228
229      pointer
230      data() noexcept
231      { return _AT_Type::_S_ptr(_M_elems); }
232
233      const_pointer
234      data() const noexcept
235      { return _AT_Type::_S_ptr(_M_elems); }
236    };
237
238  // Array comparisons.
239  template<typename _Tp, std::size_t _Nm>
240    inline bool
241    operator==(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
242    { return std::equal(__one.begin(), __one.end(), __two.begin()); }
243
244  template<typename _Tp, std::size_t _Nm>
245    inline bool
246    operator!=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
247    { return !(__one == __two); }
248
249  template<typename _Tp, std::size_t _Nm>
250    inline bool
251    operator<(const array<_Tp, _Nm>& __a, const array<_Tp, _Nm>& __b)
252    {
253      return std::lexicographical_compare(__a.begin(), __a.end(),
254					  __b.begin(), __b.end());
255    }
256
257  template<typename _Tp, std::size_t _Nm>
258    inline bool
259    operator>(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
260    { return __two < __one; }
261
262  template<typename _Tp, std::size_t _Nm>
263    inline bool
264    operator<=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
265    { return !(__one > __two); }
266
267  template<typename _Tp, std::size_t _Nm>
268    inline bool
269    operator>=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
270    { return !(__one < __two); }
271
272  // Specialized algorithms.
273  template<typename _Tp, std::size_t _Nm>
274    inline void
275    swap(array<_Tp, _Nm>& __one, array<_Tp, _Nm>& __two)
276    noexcept(noexcept(__one.swap(__two)))
277    { __one.swap(__two); }
278
279  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
280    constexpr _Tp&
281    get(array<_Tp, _Nm>& __arr) noexcept
282    {
283      static_assert(_Int < _Nm, "index is out of bounds");
284      return _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::
285	_S_ref(__arr._M_elems, _Int);
286    }
287
288  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
289    constexpr _Tp&&
290    get(array<_Tp, _Nm>&& __arr) noexcept
291    {
292      static_assert(_Int < _Nm, "index is out of bounds");
293      return std::move(_GLIBCXX_STD_C::get<_Int>(__arr));
294    }
295
296  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
297    constexpr const _Tp&
298    get(const array<_Tp, _Nm>& __arr) noexcept
299    {
300      static_assert(_Int < _Nm, "index is out of bounds");
301      return _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::
302	_S_ref(__arr._M_elems, _Int);
303    }
304
305_GLIBCXX_END_NAMESPACE_CONTAINER
306} // namespace std
307
308namespace std _GLIBCXX_VISIBILITY(default)
309{
310_GLIBCXX_BEGIN_NAMESPACE_VERSION
311
312  // Tuple interface to class template array.
313
314  /// tuple_size
315  template<typename _Tp>
316    class tuple_size;
317
318  /// Partial specialization for std::array
319  template<typename _Tp, std::size_t _Nm>
320    struct tuple_size<_GLIBCXX_STD_C::array<_Tp, _Nm>>
321    : public integral_constant<std::size_t, _Nm> { };
322
323  /// tuple_element
324  template<std::size_t _Int, typename _Tp>
325    class tuple_element;
326
327  /// Partial specialization for std::array
328  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
329    struct tuple_element<_Int, _GLIBCXX_STD_C::array<_Tp, _Nm>>
330    {
331      static_assert(_Int < _Nm, "index is out of bounds");
332      typedef _Tp type;
333    };
334
335  template<typename _Tp, std::size_t _Nm>
336    struct __is_tuple_like_impl<_GLIBCXX_STD_C::array<_Tp, _Nm>> : true_type
337    { };
338
339_GLIBCXX_END_NAMESPACE_VERSION
340} // namespace std
341
342#ifdef _GLIBCXX_DEBUG
343# include <debug/array>
344#endif
345
346#ifdef _GLIBCXX_PROFILE
347# include <profile/array>
348#endif
349
350#endif // C++11
351
352#endif // _GLIBCXX_ARRAY
353