libstdc++
array
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1 // <array> -*- C++ -*-
2 
3 // Copyright (C) 2007-2017 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  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;
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  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...)
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 _GLIBCXX_END_NAMESPACE_CONTAINER
332 } // namespace std
333 
334 namespace std _GLIBCXX_VISIBILITY(default)
335 {
336 _GLIBCXX_BEGIN_NAMESPACE_VERSION
337 
338  // Tuple interface to class template array.
339 
340  /// tuple_size
341  template<typename _Tp>
342  class tuple_size;
343 
344  /// Partial specialization for std::array
345  template<typename _Tp, std::size_t _Nm>
346  struct tuple_size<_GLIBCXX_STD_C::array<_Tp, _Nm>>
347  : public integral_constant<std::size_t, _Nm> { };
348 
349  /// tuple_element
350  template<std::size_t _Int, typename _Tp>
352 
353  /// Partial specialization for std::array
354  template<std::size_t _Int, typename _Tp, std::size_t _Nm>
355  struct tuple_element<_Int, _GLIBCXX_STD_C::array<_Tp, _Nm>>
356  {
357  static_assert(_Int < _Nm, "index is out of bounds");
358  typedef _Tp type;
359  };
360 
361  template<typename _Tp, std::size_t _Nm>
362  struct __is_tuple_like_impl<_GLIBCXX_STD_C::array<_Tp, _Nm>> : true_type
363  { };
364 
365 _GLIBCXX_END_NAMESPACE_VERSION
366 } // namespace std
367 
368 #ifdef _GLIBCXX_DEBUG
369 # include <debug/array>
370 #endif
371 
372 #ifdef _GLIBCXX_PROFILE
373 # include <profile/array>
374 #endif
375 
376 #endif // C++11
377 
378 #endif // _GLIBCXX_ARRAY
constexpr const _Tp * end(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to one past the last element of the initializer_list. ...
integral_constant
Definition: type_traits:69
constexpr auto cend(const _Container &__cont) noexcept(noexcept(std::end(__cont))) -> decltype(std::end(__cont))
Return an iterator pointing to one past the last element of the const container.
Definition: range_access.h:127
constexpr const _Tp * begin(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to the first element of the initializer_list.
ISO C++ entities toplevel namespace is std.
bool lexicographical_compare(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2, _Compare __comp)
Performs dictionary comparison on ranges.
A standard container for storing a fixed size sequence of elements.
Definition: array:94
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:87
_GLIBCXX17_CONSTEXPR auto crend(const _Container &__cont) -> decltype(std::rend(__cont))
Return a reverse iterator pointing one past the first element of the const container.
Definition: range_access.h:228
_GLIBCXX17_CONSTEXPR auto rbegin(_Container &__cont) -> decltype(__cont.rbegin())
Return a reverse iterator pointing to the last element of the container.
Definition: range_access.h:138
_GLIBCXX17_CONSTEXPR auto rend(_Container &__cont) -> decltype(__cont.rend())
Return a reverse iterator pointing one past the first element of the container.
Definition: range_access.h:158
_GLIBCXX17_CONSTEXPR auto crbegin(const _Container &__cont) -> decltype(std::rbegin(__cont))
Return a reverse iterator pointing to the last element of the const container.
Definition: range_access.h:218
tuple_size
Definition: array:342
_ForwardIterator2 swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2)
Swap the elements of two sequences.
Definition: stl_algobase.h:166
_OI fill_n(_OI __first, _Size __n, const _Tp &__value)
Fills the range [first,first+n) with copies of value.
Definition: stl_algobase.h:784
tuple_element
Definition: array:351
constexpr auto cbegin(const _Container &__cont) noexcept(noexcept(std::begin(__cont))) -> decltype(std::begin(__cont))
Return an iterator pointing to the first element of the const container.
Definition: range_access.h:116
bool equal(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _IIter2 __last2, _BinaryPredicate __binary_pred)
Tests a range for element-wise equality.