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The C and C++ Include Header Files

/usr/include/c++/13/experimental/array


$ cat -n /usr/include/c++/13/experimental/array

     1	// <experimental/array> -*- C++ -*-
     2	
     3	// Copyright (C) 2015-2023 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	#include <bits/requires_hosted.h> // experimental is currently omitted
    36	
    37	#if __cplusplus >= 201402L
    38	
    39	#include <array>
    40	#include <experimental/type_traits>
    41	
    42	namespace std _GLIBCXX_VISIBILITY(default)
    43	{
    44	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    45	
    46	namespace experimental
    47	{
    48	inline namespace fundamentals_v2
    49	{
    50	#define __cpp_lib_experimental_make_array 201505
    51	  /**
    52	   * @defgroup make_array Array creation functions
    53	   * @ingroup libfund-ts
    54	   *
    55	   * Array creation functions as described in N4529,
    56	   * Working Draft, C++ Extensions for Library Fundamentals, Version 2
    57	   *
    58	   * @{
    59	   */
    60	
    61	template<typename _Dest, typename... _Types>
    62	  struct __make_array_elem
    63	  {
    64	    using type = _Dest;
    65	  };
    66	
    67	template<typename... _Types>
    68	  struct __make_array_elem<void, _Types...>
    69	  : common_type<_Types...>
    70	  {
    71	    template <typename>
    72	      struct __is_reference_wrapper : false_type
    73	      {};
    74	
    75	    template <typename _Up>
    76	      struct __is_reference_wrapper<reference_wrapper<_Up>> : true_type
    77	      {};
    78	
    79	    static_assert(!__or_<__is_reference_wrapper<decay_t<_Types>>...>::value,
    80	                  "make_array must be used with an explicit target type when"
    81	                  "any of the arguments is a reference_wrapper");
    82	  };
    83	
    84	/// Create a std::array from a variable-length list of arguments.
    85	template <typename _Dest = void, typename... _Types>
    86	  constexpr
    87	  array<typename __make_array_elem<_Dest, _Types...>::type, sizeof...(_Types)>
    88	  make_array(_Types&&... __t)
    89	  {
    90	    return {{ std::forward<_Types>(__t)... }};
    91	  }
    92	
    93	template <typename _Tp, size_t _Nm, size_t... _Idx>
    94	  constexpr array<remove_cv_t<_Tp>, _Nm>
    95	  __to_array(_Tp (&__a)[_Nm], index_sequence<_Idx...>)
    96	  {
    97	    return {{__a[_Idx]...}};
    98	  }
    99	
   100	/// Create a std::array from an array.
   101	template <typename _Tp, size_t _Nm>
   102	  constexpr array<remove_cv_t<_Tp>, _Nm>
   103	  to_array(_Tp (&__a)[_Nm])
   104	  noexcept(is_nothrow_constructible<remove_cv_t<_Tp>, _Tp&>::value)
   105	  {
   106	    return experimental::__to_array(__a, make_index_sequence<_Nm>{});
   107	  }
   108	
   109	  /// @} group make_array
   110	} // namespace fundamentals_v2
   111	} // namespace experimental
   112	
   113	_GLIBCXX_END_NAMESPACE_VERSION
   114	} // namespace std
   115	
   116	#endif // C++14
   117	
   118	#endif // _GLIBCXX_EXPERIMENTAL_ARRAY