libstdc++
array
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00001 // <experimental/array> -*- C++ -*-
00002 
00003 // Copyright (C) 2015-2017 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /** @file experimental/array
00026  *  This is a TS C++ Library header.
00027  */
00028 
00029 #ifndef _GLIBCXX_EXPERIMENTAL_ARRAY
00030 #define _GLIBCXX_EXPERIMENTAL_ARRAY 1
00031 
00032 #pragma GCC system_header
00033 
00034 #if __cplusplus <= 201103L
00035 # include <bits/c++14_warning.h>
00036 #else
00037 
00038 #include <array>
00039 #include <experimental/type_traits>
00040 
00041 namespace std _GLIBCXX_VISIBILITY(default)
00042 {
00043 namespace experimental
00044 {
00045 inline namespace fundamentals_v2
00046 {
00047 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00048 
00049 #define __cpp_lib_experimental_make_array 201505
00050   /**
00051    * @defgroup make_array Array creation functions
00052    * @ingroup experimental
00053    *
00054    * Array creation functions as described in N4529,
00055    * Working Draft, C++ Extensions for Library Fundamentals, Version 2
00056    *
00057    * @{
00058    */
00059 
00060 template<typename _Dest, typename... _Types>
00061   struct __make_array_elem
00062   {
00063     using type = _Dest;
00064   };
00065 
00066 template<typename... _Types>
00067   struct __make_array_elem<void, _Types...>
00068   : common_type<_Types...>
00069   {
00070     template <typename>
00071       struct __is_reference_wrapper : false_type
00072       {};
00073 
00074     template <typename _Up>
00075       struct __is_reference_wrapper<reference_wrapper<_Up>> : true_type
00076       {};
00077 
00078     static_assert(!__or_<__is_reference_wrapper<decay_t<_Types>>...>::value,
00079                   "make_array must be used with an explicit target type when"
00080                   "any of the arguments is a reference_wrapper");
00081   };
00082 
00083 template <typename _Dest = void, typename... _Types>
00084   constexpr
00085   array<typename __make_array_elem<_Dest, _Types...>::type, sizeof...(_Types)>
00086   make_array(_Types&&... __t)
00087   {
00088     return {{ std::forward<_Types>(__t)... }};
00089   }
00090 
00091 template <typename _Tp, size_t _Nm, size_t... _Idx>
00092   constexpr array<remove_cv_t<_Tp>, _Nm>
00093   __to_array(_Tp (&__a)[_Nm], index_sequence<_Idx...>)
00094   {
00095     return {{__a[_Idx]...}};
00096   }
00097 
00098 template <typename _Tp, size_t _Nm>
00099   constexpr array<remove_cv_t<_Tp>, _Nm>
00100   to_array(_Tp (&__a)[_Nm])
00101   noexcept(is_nothrow_constructible<remove_cv_t<_Tp>, _Tp&>::value)
00102   {
00103     return __to_array(__a, make_index_sequence<_Nm>{});
00104   }
00105 
00106   // @} group make_array
00107   _GLIBCXX_END_NAMESPACE_VERSION
00108 } // namespace fundamentals_v2
00109 } // namespace experimental
00110 
00111 } // namespace std
00112 
00113 #endif // C++14
00114 
00115 #endif // _GLIBCXX_EXPERIMENTAL_ARRAY