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// <experimental/array> -*- C++ -*- |
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// Copyright (C) 2015-2021 Free Software Foundation, Inc. |
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// |
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// This file is part of the GNU ISO C++ Library. This library is free |
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// software; you can redistribute it and/or modify it under the |
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// terms of the GNU General Public License as published by the |
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// Free Software Foundation; either version 3, or (at your option) |
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// any later version. |
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// This library is distributed in the hope that it will be useful, |
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// but WITHOUT ANY WARRANTY; without even the implied warranty of |
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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// GNU General Public License for more details. |
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|
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// Under Section 7 of GPL version 3, you are granted additional |
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// permissions described in the GCC Runtime Library Exception, version |
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// 3.1, as published by the Free Software Foundation. |
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// You should have received a copy of the GNU General Public License and |
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// a copy of the GCC Runtime Library Exception along with this program; |
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
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// <http://www.gnu.org/licenses/>. |
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|
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/** @file experimental/array |
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* This is a TS C++ Library header. |
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* @ingroup libfund-ts |
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*/ |
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#ifndef _GLIBCXX_EXPERIMENTAL_ARRAY |
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#define _GLIBCXX_EXPERIMENTAL_ARRAY 1 |
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#pragma GCC system_header |
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#if __cplusplus >= 201402L |
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#include <array> |
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#include <experimental/type_traits> |
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|
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namespace std _GLIBCXX_VISIBILITY(default) |
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{ |
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_GLIBCXX_BEGIN_NAMESPACE_VERSION |
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|
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namespace experimental |
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{ |
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inline namespace fundamentals_v2 |
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{ |
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#define __cpp_lib_experimental_make_array 201505 |
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/** |
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* @defgroup make_array Array creation functions |
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* @ingroup libfund-ts |
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* |
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* Array creation functions as described in N4529, |
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* Working Draft, C++ Extensions for Library Fundamentals, Version 2 |
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* |
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* @{ |
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*/ |
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|
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template<typename _Dest, typename... _Types> |
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struct __make_array_elem |
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{ |
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using type = _Dest; |
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}; |
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template<typename... _Types> |
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struct __make_array_elem<void, _Types...> |
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: common_type<_Types...> |
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{ |
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template <typename> |
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struct __is_reference_wrapper : false_type |
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{}; |
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|
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template <typename _Up> |
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struct __is_reference_wrapper<reference_wrapper<_Up>> : true_type |
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{}; |
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|
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static_assert(!__or_<__is_reference_wrapper<decay_t<_Types>>...>::value, |
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"make_array must be used with an explicit target type when" |
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"any of the arguments is a reference_wrapper"); |
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}; |
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/// Create a std::array from a variable-length list of arguments. |
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template <typename _Dest = void, typename... _Types> |
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constexpr |
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array<typename __make_array_elem<_Dest, _Types...>::type, sizeof...(_Types)> |
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make_array(_Types&&... __t) |
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{ |
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return {{ std::forward<_Types>(__t)... }}; |
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} |
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template <typename _Tp, size_t _Nm, size_t... _Idx> |
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constexpr array<remove_cv_t<_Tp>, _Nm> |
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__to_array(_Tp (&__a)[_Nm], index_sequence<_Idx...>) |
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{ |
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return {{__a[_Idx]...}}; |
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} |
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/// Create a std::array from an array. |
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template <typename _Tp, size_t _Nm> |
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constexpr array<remove_cv_t<_Tp>, _Nm> |
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to_array(_Tp (&__a)[_Nm]) |
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noexcept(is_nothrow_constructible<remove_cv_t<_Tp>, _Tp&>::value) |
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{ |
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return experimental::__to_array(__a, make_index_sequence<_Nm>{}); |
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} |
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/// @} group make_array |
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} // namespace fundamentals_v2 |
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} // namespace experimental |
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_GLIBCXX_END_NAMESPACE_VERSION |
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} // namespace std |
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#endif // C++14 |
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#endif // _GLIBCXX_EXPERIMENTAL_ARRAY |
