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The C and C++ Include Header Files

/usr/include/c++/11/experimental/array


$ cat -n /usr/include/c++/11/experimental/array

     1	// <experimental/array> -*- C++ -*-
     2	
     3	// Copyright (C) 2015-2021 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 experimental/array
    26	 *  This is a TS C++ Library header.
    27	 *  @ingroup libfund-ts
    28	 */
    29	
    30	#ifndef _GLIBCXX_EXPERIMENTAL_ARRAY
    31	#define _GLIBCXX_EXPERIMENTAL_ARRAY 1
    32	
    33	#pragma GCC system_header
    34	
    35	#if __cplusplus >= 201402L
    36	
    37	#include <array>
    38	#include <experimental/type_traits>
    39	
    40	namespace std _GLIBCXX_VISIBILITY(default)
    41	{
    42	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    43	
    44	namespace experimental
    45	{
    46	inline namespace fundamentals_v2
    47	{
    48	#define __cpp_lib_experimental_make_array 201505
    49	  /**
    50	   * @defgroup make_array Array creation functions
    51	   * @ingroup libfund-ts
    52	   *
    53	   * Array creation functions as described in N4529,
    54	   * Working Draft, C++ Extensions for Library Fundamentals, Version 2
    55	   *
    56	   * @{
    57	   */
    58	
    59	template<typename _Dest, typename... _Types>
    60	  struct __make_array_elem
    61	  {
    62	    using type = _Dest;
    63	  };
    64	
    65	template<typename... _Types>
    66	  struct __make_array_elem<void, _Types...>
    67	  : common_type<_Types...>
    68	  {
    69	    template <typename>
    70	      struct __is_reference_wrapper : false_type
    71	      {};
    72	
    73	    template <typename _Up>
    74	      struct __is_reference_wrapper<reference_wrapper<_Up>> : true_type
    75	      {};
    76	
    77	    static_assert(!__or_<__is_reference_wrapper<decay_t<_Types>>...>::value,
    78	                  "make_array must be used with an explicit target type when"
    79	                  "any of the arguments is a reference_wrapper");
    80	  };
    81	
    82	/// Create a std::array from a variable-length list of arguments.
    83	template <typename _Dest = void, typename... _Types>
    84	  constexpr
    85	  array<typename __make_array_elem<_Dest, _Types...>::type, sizeof...(_Types)>
    86	  make_array(_Types&&... __t)
    87	  {
    88	    return {{ std::forward<_Types>(__t)... }};
    89	  }
    90	
    91	template <typename _Tp, size_t _Nm, size_t... _Idx>
    92	  constexpr array<remove_cv_t<_Tp>, _Nm>
    93	  __to_array(_Tp (&__a)[_Nm], index_sequence<_Idx...>)
    94	  {
    95	    return {{__a[_Idx]...}};
    96	  }
    97	
    98	/// Create a std::array from an array.
    99	template <typename _Tp, size_t _Nm>
   100	  constexpr array<remove_cv_t<_Tp>, _Nm>
   101	  to_array(_Tp (&__a)[_Nm])
   102	  noexcept(is_nothrow_constructible<remove_cv_t<_Tp>, _Tp&>::value)
   103	  {
   104	    return experimental::__to_array(__a, make_index_sequence<_Nm>{});
   105	  }
   106	
   107	  /// @} group make_array
   108	} // namespace fundamentals_v2
   109	} // namespace experimental
   110	
   111	_GLIBCXX_END_NAMESPACE_VERSION
   112	} // namespace std
   113	
   114	#endif // C++14
   115	
   116	#endif // _GLIBCXX_EXPERIMENTAL_ARRAY