libstdc++
array
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1 // <array> -*- C++ -*-
2 
3 // Copyright (C) 2007-2015 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 <stdexcept>
39 #include <bits/stl_algobase.h>
40 #include <bits/range_access.h>
41 
42 namespace std _GLIBCXX_VISIBILITY(default)
43 {
44 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
45 
46  template<typename _Tp, std::size_t _Nm>
47  struct __array_traits
48  {
49  typedef _Tp _Type[_Nm];
50 
51  static constexpr _Tp&
52  _S_ref(const _Type& __t, std::size_t __n) noexcept
53  { return const_cast<_Tp&>(__t[__n]); }
54 
55  static constexpr _Tp*
56  _S_ptr(const _Type& __t) noexcept
57  { return const_cast<_Tp*>(__t); }
58  };
59 
60  template<typename _Tp>
61  struct __array_traits<_Tp, 0>
62  {
63  struct _Type { };
64 
65  static constexpr _Tp&
66  _S_ref(const _Type&, std::size_t) noexcept
67  { return *static_cast<_Tp*>(nullptr); }
68 
69  static constexpr _Tp*
70  _S_ptr(const _Type&) noexcept
71  { return nullptr; }
72  };
73 
74  /**
75  * @brief A standard container for storing a fixed size sequence of elements.
76  *
77  * @ingroup sequences
78  *
79  * Meets the requirements of a <a href="tables.html#65">container</a>, a
80  * <a href="tables.html#66">reversible container</a>, and a
81  * <a href="tables.html#67">sequence</a>.
82  *
83  * Sets support random access iterators.
84  *
85  * @tparam Tp Type of element. Required to be a complete type.
86  * @tparam N Number of elements.
87  */
88  template<typename _Tp, std::size_t _Nm>
89  struct array
90  {
91  typedef _Tp value_type;
92  typedef value_type* pointer;
93  typedef const value_type* const_pointer;
94  typedef value_type& reference;
95  typedef const value_type& const_reference;
96  typedef value_type* iterator;
97  typedef const value_type* const_iterator;
98  typedef std::size_t size_type;
99  typedef std::ptrdiff_t difference_type;
100  typedef std::reverse_iterator<iterator> reverse_iterator;
101  typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
102 
103  // Support for zero-sized arrays mandatory.
104  typedef _GLIBCXX_STD_C::__array_traits<_Tp, _Nm> _AT_Type;
105  typename _AT_Type::_Type _M_elems;
106 
107  // No explicit construct/copy/destroy for aggregate type.
108 
109  // DR 776.
110  void
111  fill(const value_type& __u)
112  { std::fill_n(begin(), size(), __u); }
113 
114  void
115  swap(array& __other)
116  noexcept(noexcept(swap(std::declval<_Tp&>(), std::declval<_Tp&>())))
117  { std::swap_ranges(begin(), end(), __other.begin()); }
118 
119  // Iterators.
120  iterator
121  begin() noexcept
122  { return iterator(data()); }
123 
124  const_iterator
125  begin() const noexcept
126  { return const_iterator(data()); }
127 
128  iterator
129  end() noexcept
130  { return iterator(data() + _Nm); }
131 
132  const_iterator
133  end() const noexcept
134  { return const_iterator(data() + _Nm); }
135 
136  reverse_iterator
137  rbegin() noexcept
138  { return reverse_iterator(end()); }
139 
140  const_reverse_iterator
141  rbegin() const noexcept
142  { return const_reverse_iterator(end()); }
143 
144  reverse_iterator
145  rend() noexcept
146  { return reverse_iterator(begin()); }
147 
148  const_reverse_iterator
149  rend() const noexcept
150  { return const_reverse_iterator(begin()); }
151 
152  const_iterator
153  cbegin() const noexcept
154  { return const_iterator(data()); }
155 
156  const_iterator
157  cend() const noexcept
158  { return const_iterator(data() + _Nm); }
159 
160  const_reverse_iterator
161  crbegin() const noexcept
162  { return const_reverse_iterator(end()); }
163 
164  const_reverse_iterator
165  crend() const noexcept
166  { return const_reverse_iterator(begin()); }
167 
168  // Capacity.
169  constexpr size_type
170  size() const noexcept { return _Nm; }
171 
172  constexpr size_type
173  max_size() const noexcept { return _Nm; }
174 
175  constexpr bool
176  empty() const noexcept { return size() == 0; }
177 
178  // Element access.
179  reference
180  operator[](size_type __n) noexcept
181  { return _AT_Type::_S_ref(_M_elems, __n); }
182 
183  constexpr const_reference
184  operator[](size_type __n) const noexcept
185  { return _AT_Type::_S_ref(_M_elems, __n); }
186 
187  reference
188  at(size_type __n)
189  {
190  if (__n >= _Nm)
191  std::__throw_out_of_range_fmt(__N("array::at: __n (which is %zu) "
192  ">= _Nm (which is %zu)"),
193  __n, _Nm);
194  return _AT_Type::_S_ref(_M_elems, __n);
195  }
196 
197  constexpr const_reference
198  at(size_type __n) const
199  {
200  // Result of conditional expression must be an lvalue so use
201  // boolean ? lvalue : (throw-expr, lvalue)
202  return __n < _Nm ? _AT_Type::_S_ref(_M_elems, __n)
203  : (std::__throw_out_of_range_fmt(__N("array::at: __n (which is %zu) "
204  ">= _Nm (which is %zu)"),
205  __n, _Nm),
206  _AT_Type::_S_ref(_M_elems, 0));
207  }
208 
209  reference
210  front() noexcept
211  { return *begin(); }
212 
213  constexpr const_reference
214  front() const noexcept
215  { return _AT_Type::_S_ref(_M_elems, 0); }
216 
217  reference
218  back() noexcept
219  { return _Nm ? *(end() - 1) : *end(); }
220 
221  constexpr const_reference
222  back() const noexcept
223  {
224  return _Nm ? _AT_Type::_S_ref(_M_elems, _Nm - 1)
225  : _AT_Type::_S_ref(_M_elems, 0);
226  }
227 
228  pointer
229  data() noexcept
230  { return _AT_Type::_S_ptr(_M_elems); }
231 
232  const_pointer
233  data() const noexcept
234  { return _AT_Type::_S_ptr(_M_elems); }
235  };
236 
237  // Array comparisons.
238  template<typename _Tp, std::size_t _Nm>
239  inline bool
240  operator==(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
241  { return std::equal(__one.begin(), __one.end(), __two.begin()); }
242 
243  template<typename _Tp, std::size_t _Nm>
244  inline bool
245  operator!=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
246  { return !(__one == __two); }
247 
248  template<typename _Tp, std::size_t _Nm>
249  inline bool
250  operator<(const array<_Tp, _Nm>& __a, const array<_Tp, _Nm>& __b)
251  {
252  return std::lexicographical_compare(__a.begin(), __a.end(),
253  __b.begin(), __b.end());
254  }
255 
256  template<typename _Tp, std::size_t _Nm>
257  inline bool
258  operator>(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
259  { return __two < __one; }
260 
261  template<typename _Tp, std::size_t _Nm>
262  inline bool
263  operator<=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
264  { return !(__one > __two); }
265 
266  template<typename _Tp, std::size_t _Nm>
267  inline bool
268  operator>=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
269  { return !(__one < __two); }
270 
271  // Specialized algorithms.
272  template<typename _Tp, std::size_t _Nm>
273  inline void
274  swap(array<_Tp, _Nm>& __one, array<_Tp, _Nm>& __two)
275  noexcept(noexcept(__one.swap(__two)))
276  { __one.swap(__two); }
277 
278  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
279  constexpr _Tp&
280  get(array<_Tp, _Nm>& __arr) noexcept
281  {
282  static_assert(_Int < _Nm, "index is out of bounds");
283  return _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::
284  _S_ref(__arr._M_elems, _Int);
285  }
286 
287  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
288  constexpr _Tp&&
289  get(array<_Tp, _Nm>&& __arr) noexcept
290  {
291  static_assert(_Int < _Nm, "index is out of bounds");
292  return std::move(_GLIBCXX_STD_C::get<_Int>(__arr));
293  }
294 
295  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
296  constexpr const _Tp&
297  get(const array<_Tp, _Nm>& __arr) noexcept
298  {
299  static_assert(_Int < _Nm, "index is out of bounds");
300  return _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::
301  _S_ref(__arr._M_elems, _Int);
302  }
303 
304 _GLIBCXX_END_NAMESPACE_CONTAINER
305 } // namespace std
306 
307 namespace std _GLIBCXX_VISIBILITY(default)
308 {
309 _GLIBCXX_BEGIN_NAMESPACE_VERSION
310 
311  // Tuple interface to class template array.
312 
313  /// tuple_size
314  template<typename _Tp>
315  class tuple_size;
316 
317  /// Partial specialization for std::array
318  template<typename _Tp, std::size_t _Nm>
319  struct tuple_size<_GLIBCXX_STD_C::array<_Tp, _Nm>>
320  : public integral_constant<std::size_t, _Nm> { };
321 
322  /// tuple_element
323  template<std::size_t _Int, typename _Tp>
324  class tuple_element;
325 
326  /// Partial specialization for std::array
327  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
328  struct tuple_element<_Int, _GLIBCXX_STD_C::array<_Tp, _Nm>>
329  {
330  static_assert(_Int < _Nm, "index is out of bounds");
331  typedef _Tp type;
332  };
333 
334 _GLIBCXX_END_NAMESPACE_VERSION
335 } // namespace std
336 
337 #ifdef _GLIBCXX_DEBUG
338 # include <debug/array>
339 #endif
340 
341 #ifdef _GLIBCXX_PROFILE
342 # include <profile/array>
343 #endif
344 
345 #endif // C++11
346 
347 #endif // _GLIBCXX_ARRAY