libstdc++
array
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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 
43 namespace 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 
308 namespace 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