Where Online Learning is simpler!
The C and C++ Include Header Files
/usr/include/c++/11/bits/uses_allocator.h
$ cat -n /usr/include/c++/11/bits/uses_allocator.h 1 // Uses-allocator Construction -*- C++ -*- 2 3 // Copyright (C) 2010-2021 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 #ifndef _USES_ALLOCATOR_H 26 #define _USES_ALLOCATOR_H 1 27 28 #if __cplusplus < 201103L 29 # include <bits/c++0x_warning.h> 30 #else 31 32 #include <type_traits> 33 #include <bits/move.h> 34 35 namespace std _GLIBCXX_VISIBILITY(default) 36 { 37 _GLIBCXX_BEGIN_NAMESPACE_VERSION 38 /// @cond undocumented 39 40 // This is used for std::experimental::erased_type from Library Fundamentals. 41 struct __erased_type { }; 42 43 // This also supports the "type-erased allocator" protocol from the 44 // Library Fundamentals TS, where allocator_type is erased_type. 45 // The second condition will always be false for types not using the TS. 46 template<typename _Alloc, typename _Tp> 47 using __is_erased_or_convertible 48 = __or_<is_convertible<_Alloc, _Tp>, is_same<_Tp, __erased_type>>; 49 50 /// [allocator.tag] 51 struct allocator_arg_t { explicit allocator_arg_t() = default; }; 52 53 _GLIBCXX17_INLINE constexpr allocator_arg_t allocator_arg = 54 allocator_arg_t(); 55 56 template<typename _Tp, typename _Alloc, typename = __void_t<>> 57 struct __uses_allocator_helper 58 : false_type { }; 59 60 template<typename _Tp, typename _Alloc> 61 struct __uses_allocator_helper<_Tp, _Alloc, 62 __void_t<typename _Tp::allocator_type>> 63 : __is_erased_or_convertible<_Alloc, typename _Tp::allocator_type>::type 64 { }; 65 66 /// [allocator.uses.trait] 67 template<typename _Tp, typename _Alloc> 68 struct uses_allocator 69 : __uses_allocator_helper<_Tp, _Alloc>::type 70 { }; 71 72 struct __uses_alloc_base { }; 73 74 struct __uses_alloc0 : __uses_alloc_base 75 { 76 struct _Sink { void _GLIBCXX20_CONSTEXPR operator=(const void*) { } } _M_a; 77 }; 78 79 template<typename _Alloc> 80 struct __uses_alloc1 : __uses_alloc_base { const _Alloc* _M_a; }; 81 82 template<typename _Alloc> 83 struct __uses_alloc2 : __uses_alloc_base { const _Alloc* _M_a; }; 84 85 template<bool, typename _Tp, typename _Alloc, typename... _Args> 86 struct __uses_alloc; 87 88 template<typename _Tp, typename _Alloc, typename... _Args> 89 struct __uses_alloc<true, _Tp, _Alloc, _Args...> 90 : conditional< 91 is_constructible<_Tp, allocator_arg_t, const _Alloc&, _Args...>::value, 92 __uses_alloc1<_Alloc>, 93 __uses_alloc2<_Alloc>>::type 94 { 95 // _GLIBCXX_RESOLVE_LIB_DEFECTS 96 // 2586. Wrong value category used in scoped_allocator_adaptor::construct 97 static_assert(__or_< 98 is_constructible<_Tp, allocator_arg_t, const _Alloc&, _Args...>, 99 is_constructible<_Tp, _Args..., const _Alloc&>>::value, 100 "construction with an allocator must be possible" 101 " if uses_allocator is true"); 102 }; 103 104 template<typename _Tp, typename _Alloc, typename... _Args> 105 struct __uses_alloc<false, _Tp, _Alloc, _Args...> 106 : __uses_alloc0 { }; 107 108 template<typename _Tp, typename _Alloc, typename... _Args> 109 using __uses_alloc_t = 110 __uses_alloc<uses_allocator<_Tp, _Alloc>::value, _Tp, _Alloc, _Args...>; 111 112 template<typename _Tp, typename _Alloc, typename... _Args> 113 _GLIBCXX20_CONSTEXPR 114 inline __uses_alloc_t<_Tp, _Alloc, _Args...> 115 __use_alloc(const _Alloc& __a) 116 { 117 __uses_alloc_t<_Tp, _Alloc, _Args...> __ret; 118 __ret._M_a = std::__addressof(__a); 119 return __ret; 120 } 121 122 template<typename _Tp, typename _Alloc, typename... _Args> 123 void 124 __use_alloc(const _Alloc&&) = delete; 125 126 #if __cplusplus > 201402L 127 template <typename _Tp, typename _Alloc> 128 inline constexpr bool uses_allocator_v = 129 uses_allocator<_Tp, _Alloc>::value; 130 #endif // C++17 131 132 template<template<typename...> class _Predicate, 133 typename _Tp, typename _Alloc, typename... _Args> 134 struct __is_uses_allocator_predicate 135 : conditional<uses_allocator<_Tp, _Alloc>::value, 136 __or_<_Predicate<_Tp, allocator_arg_t, _Alloc, _Args...>, 137 _Predicate<_Tp, _Args..., _Alloc>>, 138 _Predicate<_Tp, _Args...>>::type { }; 139 140 template<typename _Tp, typename _Alloc, typename... _Args> 141 struct __is_uses_allocator_constructible 142 : __is_uses_allocator_predicate<is_constructible, _Tp, _Alloc, _Args...> 143 { }; 144 145 #if __cplusplus >= 201402L 146 template<typename _Tp, typename _Alloc, typename... _Args> 147 _GLIBCXX17_INLINE constexpr bool __is_uses_allocator_constructible_v = 148 __is_uses_allocator_constructible<_Tp, _Alloc, _Args...>::value; 149 #endif // C++14 150 151 template<typename _Tp, typename _Alloc, typename... _Args> 152 struct __is_nothrow_uses_allocator_constructible 153 : __is_uses_allocator_predicate<is_nothrow_constructible, 154 _Tp, _Alloc, _Args...> 155 { }; 156 157 158 #if __cplusplus >= 201402L 159 template<typename _Tp, typename _Alloc, typename... _Args> 160 _GLIBCXX17_INLINE constexpr bool 161 __is_nothrow_uses_allocator_constructible_v = 162 __is_nothrow_uses_allocator_constructible<_Tp, _Alloc, _Args...>::value; 163 #endif // C++14 164 165 template<typename _Tp, typename... _Args> 166 void __uses_allocator_construct_impl(__uses_alloc0 __a, _Tp* __ptr, 167 _Args&&... __args) 168 { ::new ((void*)__ptr) _Tp(std::forward<_Args>(__args)...); } 169 170 template<typename _Tp, typename _Alloc, typename... _Args> 171 void __uses_allocator_construct_impl(__uses_alloc1<_Alloc> __a, _Tp* __ptr, 172 _Args&&... __args) 173 { 174 ::new ((void*)__ptr) _Tp(allocator_arg, *__a._M_a, 175 std::forward<_Args>(__args)...); 176 } 177 178 template<typename _Tp, typename _Alloc, typename... _Args> 179 void __uses_allocator_construct_impl(__uses_alloc2<_Alloc> __a, _Tp* __ptr, 180 _Args&&... __args) 181 { ::new ((void*)__ptr) _Tp(std::forward<_Args>(__args)..., *__a._M_a); } 182 183 template<typename _Tp, typename _Alloc, typename... _Args> 184 void __uses_allocator_construct(const _Alloc& __a, _Tp* __ptr, 185 _Args&&... __args) 186 { 187 std::__uses_allocator_construct_impl( 188 std::__use_alloc<_Tp, _Alloc, _Args...>(__a), __ptr, 189 std::forward<_Args>(__args)...); 190 } 191 192 /// @endcond 193 _GLIBCXX_END_NAMESPACE_VERSION 194 } // namespace std 195 196 #endif 197 #endif
Contact us
|
About us
|
Term of use
|
Copyright © 2000-2025 MyWebUniversity.com ™
