libstdc++-v3/include/std/array

   1 // <array> -*- C++ -*-
   2
   3 // Copyright (C) 2007-2012 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 #ifndef __GXX_EXPERIMENTAL_CXX0X__
  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
  56  template<typename _Tp>
  57    struct __array_traits<_Tp, 0>
  58    {
  59      struct _Type { };
  60
  61      static constexpr _Tp&
  62      _S_ref(const _Type&, std::size_t) noexcept
  63      { return *static_cast<_Tp*>(nullptr); }
  64    };
  65
  66   /**
  67    *  @brief A standard container for storing a fixed size sequence of elements.
  68    *
  69    *  @ingroup sequences
  70    *
  71    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
  72    *  <a href="tables.html#66">reversible container</a>, and a
  73    *  <a href="tables.html#67">sequence</a>.
  74    *
  75    *  Sets support random access iterators.
  76    *
  77    *  @tparam  Tp  Type of element. Required to be a complete type.
  78    *  @tparam  N  Number of elements.
  79   */
  80   template<typename _Tp, std::size_t _Nm>
  81     struct array
  82     {
  83       typedef _Tp                                     value_type;
  84       typedef value_type*                             pointer;
  85       typedef const value_type*                       const_pointer;
  86       typedef value_type&                             reference;
  87       typedef const value_type&                       const_reference;
  88       typedef value_type*                             iterator;
  89       typedef const value_type*                       const_iterator;
  90       typedef std::size_t                             size_type;
  91       typedef std::ptrdiff_t                          difference_type;
  92       typedef std::reverse_iterator<iterator>         reverse_iterator;
  93       typedef std::reverse_iterator<const_iterator>   const_reverse_iterator;
  94
  95       // Support for zero-sized arrays mandatory.
  96       typedef _GLIBCXX_STD_C::__array_traits<_Tp, _Nm> _AT_Type;
  97       typename _AT_Type::_Type                         _M_elems;
  98
  99       // No explicit construct/copy/destroy for aggregate type.
 100
 101       // DR 776.
 102       void
 103       fill(const value_type& __u)
 104       { std::fill_n(begin(), size(), __u); }
 105
 106       void
 107       swap(array& __other)
 108       noexcept(noexcept(swap(std::declval<_Tp&>(), std::declval<_Tp&>())))
 109       { std::swap_ranges(begin(), end(), __other.begin()); }
 110
 111       // Iterators.
 112       iterator
 113       begin() noexcept
 114       { return iterator(data()); }
 115
 116       const_iterator
 117       begin() const noexcept
 118       { return const_iterator(data()); }
 119
 120       iterator
 121       end() noexcept
 122       { return iterator(data() + _Nm); }
 123
 124       const_iterator
 125       end() const noexcept
 126       { return const_iterator(data() + _Nm); }
 127
 128       reverse_iterator
 129       rbegin() noexcept
 130       { return reverse_iterator(end()); }
 131
 132       const_reverse_iterator
 133       rbegin() const noexcept
 134       { return const_reverse_iterator(end()); }
 135
 136       reverse_iterator
 137       rend() noexcept
 138       { return reverse_iterator(begin()); }
 139
 140       const_reverse_iterator
 141       rend() const noexcept
 142       { return const_reverse_iterator(begin()); }
 143
 144       const_iterator
 145       cbegin() const noexcept
 146       { return const_iterator(data()); }
 147
 148       const_iterator
 149       cend() const noexcept
 150       { return const_iterator(data() + _Nm); }
 151
 152       const_reverse_iterator
 153       crbegin() const noexcept
 154       { return const_reverse_iterator(end()); }
 155
 156       const_reverse_iterator
 157       crend() const noexcept
 158       { return const_reverse_iterator(begin()); }
 159
 160       // Capacity.
 161       constexpr size_type
 162       size() const noexcept { return _Nm; }
 163
 164       constexpr size_type
 165       max_size() const noexcept { return _Nm; }
 166
 167       constexpr bool
 168       empty() const noexcept { return size() == 0; }
 169
 170       // Element access.
 171       reference
 172       operator[](size_type __n)
 173       { return _AT_Type::_S_ref(_M_elems, __n); }
 174
 175       constexpr const_reference
 176       operator[](size_type __n) const noexcept
 177       { return _AT_Type::_S_ref(_M_elems, __n); }
 178
 179       reference
 180       at(size_type __n)
 181       {
 182         if (__n >= _Nm)
 183           std::__throw_out_of_range(__N("array::at"));
 184         return _AT_Type::_S_ref(_M_elems, __n);
 185       }
 186
 187       constexpr const_reference
 188       at(size_type __n) const
 189       {
 190         // Result of conditional expression must be an lvalue so use
 191         // boolean ? lvalue : (throw-expr, lvalue)
 192         return __n < _Nm ? _AT_Type::_S_ref(_M_elems, __n)
 193           : (std::__throw_out_of_range(__N("array::at")),
 194              _AT_Type::_S_ref(_M_elems, 0));
 195       }
 196
 197       reference
 198       front()
 199       { return *begin(); }
 200
 201       constexpr const_reference
 202       front() const
 203       { return _AT_Type::_S_ref(_M_elems, 0); }
 204
 205       reference
 206       back()
 207       { return _Nm ? *(end() - 1) : *end(); }
 208
 209       constexpr const_reference
 210       back() const
 211       {
 212         return _Nm ? _AT_Type::_S_ref(_M_elems, _Nm - 1)
 213                    : _AT_Type::_S_ref(_M_elems, 0);
 214       }
 215
 216       pointer
 217       data() noexcept
 218       { return std::__addressof(_AT_Type::_S_ref(_M_elems, 0)); }
 219
 220       const_pointer
 221       data() const noexcept
 222       { return std::__addressof(_AT_Type::_S_ref(_M_elems, 0)); }
 223     };
 224
 225   // Array comparisons.
 226   template<typename _Tp, std::size_t _Nm>
 227     inline bool
 228     operator==(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
 229     { return std::equal(__one.begin(), __one.end(), __two.begin()); }
 230
 231   template<typename _Tp, std::size_t _Nm>
 232     inline bool
 233     operator!=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
 234     { return !(__one == __two); }
 235
 236   template<typename _Tp, std::size_t _Nm>
 237     inline bool
 238     operator<(const array<_Tp, _Nm>& __a, const array<_Tp, _Nm>& __b)
 239     {
 240       return std::lexicographical_compare(__a.begin(), __a.end(),
 241                                           __b.begin(), __b.end());
 242     }
 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 __two < __one; }
 248
 249   template<typename _Tp, std::size_t _Nm>
 250     inline bool
 251     operator<=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
 252     { return !(__one > __two); }
 253
 254   template<typename _Tp, std::size_t _Nm>
 255     inline bool
 256     operator>=(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
 257     { return !(__one < __two); }
 258
 259   // Specialized algorithms.
 260   template<typename _Tp, std::size_t _Nm>
 261     inline void
 262     swap(array<_Tp, _Nm>& __one, array<_Tp, _Nm>& __two)
 263     noexcept(noexcept(__one.swap(__two)))
 264     { __one.swap(__two); }
 265
 266   // Tuple interface to class template array.
 267
 268   /// tuple_size
 269   template<typename _Tp>
 270     class tuple_size;
 271
 272   template<typename _Tp, std::size_t _Nm>
 273     struct tuple_size<array<_Tp, _Nm>>
 274     : public integral_constant<std::size_t, _Nm> { };
 275
 276   /// tuple_element
 277   template<std::size_t _Int, typename _Tp>
 278     class tuple_element;
 279
 280   template<std::size_t _Int, typename _Tp, std::size_t _Nm>
 281     struct tuple_element<_Int, array<_Tp, _Nm>>
 282     {
 283       static_assert(_Int < _Nm, "index is out of bounds");
 284       typedef _Tp type;
 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 _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::
 293         _S_ref(__arr._M_elems, _Int);
 294     }
 295
 296   template<std::size_t _Int, typename _Tp, std::size_t _Nm>
 297     constexpr _Tp&&
 298     get(array<_Tp, _Nm>&& __arr) noexcept
 299     {
 300       static_assert(_Int < _Nm, "index is out of bounds");
 301       return std::move(get<_Int>(__arr));
 302     }
 303
 304   template<std::size_t _Int, typename _Tp, std::size_t _Nm>
 305     constexpr const _Tp&
 306     get(const array<_Tp, _Nm>& __arr) noexcept
 307     {
 308       static_assert(_Int < _Nm, "index is out of bounds");
 309       return _GLIBCXX_STD_C::__array_traits<_Tp, _Nm>::
 310         _S_ref(__arr._M_elems, _Int);
 311     }
 312
 313 _GLIBCXX_END_NAMESPACE_CONTAINER
 314 } // namespace std
 315
 316 #ifdef _GLIBCXX_DEBUG
 317 # include <debug/array>
 318 #endif
 319
 320 #ifdef _GLIBCXX_PROFILE
 321 # include <profile/array>
 322 #endif
 323
 324 #endif // __GXX_EXPERIMENTAL_CXX0X__
 325
 326 #endif // _GLIBCXX_ARRAY