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Editing: uses_allocator.h
// Uses-allocator Construction -*- C++ -*- // Copyright (C) 2010-2018 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 3, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // <http://www.gnu.org/licenses/>. #ifndef _USES_ALLOCATOR_H #define _USES_ALLOCATOR_H 1 #if __cplusplus < 201103L # include <bits/c++0x_warning.h> #else #include <type_traits> #include <bits/move.h> namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION struct __erased_type { }; template<typename _Alloc, typename _Tp> using __is_erased_or_convertible = __or_<is_same<_Tp, __erased_type>, is_convertible<_Alloc, _Tp>>; /// [allocator.tag] struct allocator_arg_t { explicit allocator_arg_t() = default; }; _GLIBCXX17_INLINE constexpr allocator_arg_t allocator_arg = allocator_arg_t(); template<typename _Tp, typename _Alloc, typename = __void_t<>> struct __uses_allocator_helper : false_type { }; template<typename _Tp, typename _Alloc> struct __uses_allocator_helper<_Tp, _Alloc, __void_t<typename _Tp::allocator_type>> : __is_erased_or_convertible<_Alloc, typename _Tp::allocator_type>::type { }; /// [allocator.uses.trait] template<typename _Tp, typename _Alloc> struct uses_allocator : __uses_allocator_helper<_Tp, _Alloc>::type { }; struct __uses_alloc_base { }; struct __uses_alloc0 : __uses_alloc_base { struct _Sink { void operator=(const void*) { } } _M_a; }; template<typename _Alloc> struct __uses_alloc1 : __uses_alloc_base { const _Alloc* _M_a; }; template<typename _Alloc> struct __uses_alloc2 : __uses_alloc_base { const _Alloc* _M_a; }; template<bool, typename _Tp, typename _Alloc, typename... _Args> struct __uses_alloc; template<typename _Tp, typename _Alloc, typename... _Args> struct __uses_alloc<true, _Tp, _Alloc, _Args...> : conditional< is_constructible<_Tp, allocator_arg_t, const _Alloc&, _Args...>::value, __uses_alloc1<_Alloc>, __uses_alloc2<_Alloc>>::type { // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2586. Wrong value category used in scoped_allocator_adaptor::construct static_assert(__or_< is_constructible<_Tp, allocator_arg_t, const _Alloc&, _Args...>, is_constructible<_Tp, _Args..., const _Alloc&>>::value, "construction with an allocator must be possible" " if uses_allocator is true"); }; template<typename _Tp, typename _Alloc, typename... _Args> struct __uses_alloc<false, _Tp, _Alloc, _Args...> : __uses_alloc0 { }; template<typename _Tp, typename _Alloc, typename... _Args> using __uses_alloc_t = __uses_alloc<uses_allocator<_Tp, _Alloc>::value, _Tp, _Alloc, _Args...>; template<typename _Tp, typename _Alloc, typename... _Args> inline __uses_alloc_t<_Tp, _Alloc, _Args...> __use_alloc(const _Alloc& __a) { __uses_alloc_t<_Tp, _Alloc, _Args...> __ret; __ret._M_a = std::__addressof(__a); return __ret; } template<typename _Tp, typename _Alloc, typename... _Args> void __use_alloc(const _Alloc&&) = delete; #if __cplusplus > 201402L template <typename _Tp, typename _Alloc> inline constexpr bool uses_allocator_v = uses_allocator<_Tp, _Alloc>::value; #endif // C++17 template<template<typename...> class _Predicate, typename _Tp, typename _Alloc, typename... _Args> struct __is_uses_allocator_predicate : conditional<uses_allocator<_Tp, _Alloc>::value, __or_<_Predicate<_Tp, allocator_arg_t, _Alloc, _Args...>, _Predicate<_Tp, _Args..., _Alloc>>, _Predicate<_Tp, _Args...>>::type { }; template<typename _Tp, typename _Alloc, typename... _Args> struct __is_uses_allocator_constructible : __is_uses_allocator_predicate<is_constructible, _Tp, _Alloc, _Args...> { }; #if __cplusplus >= 201402L template<typename _Tp, typename _Alloc, typename... _Args> _GLIBCXX17_INLINE constexpr bool __is_uses_allocator_constructible_v = __is_uses_allocator_constructible<_Tp, _Alloc, _Args...>::value; #endif // C++14 template<typename _Tp, typename _Alloc, typename... _Args> struct __is_nothrow_uses_allocator_constructible : __is_uses_allocator_predicate<is_nothrow_constructible, _Tp, _Alloc, _Args...> { }; #if __cplusplus >= 201402L template<typename _Tp, typename _Alloc, typename... _Args> _GLIBCXX17_INLINE constexpr bool __is_nothrow_uses_allocator_constructible_v = __is_nothrow_uses_allocator_constructible<_Tp, _Alloc, _Args...>::value; #endif // C++14 template<typename _Tp, typename... _Args> void __uses_allocator_construct_impl(__uses_alloc0 __a, _Tp* __ptr, _Args&&... __args) { ::new ((void*)__ptr) _Tp(std::forward<_Args>(__args)...); } template<typename _Tp, typename _Alloc, typename... _Args> void __uses_allocator_construct_impl(__uses_alloc1<_Alloc> __a, _Tp* __ptr, _Args&&... __args) { ::new ((void*)__ptr) _Tp(allocator_arg, *__a._M_a, std::forward<_Args>(__args)...); } template<typename _Tp, typename _Alloc, typename... _Args> void __uses_allocator_construct_impl(__uses_alloc2<_Alloc> __a, _Tp* __ptr, _Args&&... __args) { ::new ((void*)__ptr) _Tp(std::forward<_Args>(__args)..., *__a._M_a); } template<typename _Tp, typename _Alloc, typename... _Args> void __uses_allocator_construct(const _Alloc& __a, _Tp* __ptr, _Args&&... __args) { __uses_allocator_construct_impl(__use_alloc<_Tp, _Alloc, _Args...>(__a), __ptr, std::forward<_Args>(__args)...); } _GLIBCXX_END_NAMESPACE_VERSION } // namespace std #endif #endif
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