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The C and C++ Include Header Files
cat -n /usr/include/c++/15/experimental/memory
1 // <experimental/memory> -*- C++ -*- 2 3 // Copyright (C) 2015-2025 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/memory 26 * This is a TS C++ Library header. 27 * @ingroup libfund-ts 28 */ 29 30 // 31 // N4336 Working Draft, C++ Extensions for Library Fundamentals, Version 2 32 // 33 34 #ifndef _GLIBCXX_EXPERIMENTAL_MEMORY 35 #define _GLIBCXX_EXPERIMENTAL_MEMORY 1 36 37 #ifdef _GLIBCXX_SYSHDR 38 #pragma GCC system_header 39 #endif 40 41 #include <bits/requires_hosted.h> // experimental is currently omitted 42 43 #if __cplusplus >= 201402L 44 45 #include <memory> 46 #include <type_traits> 47 #include <experimental/bits/shared_ptr.h> 48 #include <bits/functional_hash.h> 49 50 namespace std _GLIBCXX_VISIBILITY(default) 51 { 52 _GLIBCXX_BEGIN_NAMESPACE_VERSION 53 54 namespace experimental 55 { 56 inline namespace fundamentals_v2 57 { 58 #define __cpp_lib_experimental_observer_ptr 201411 59 60 template <typename _Tp> 61 class observer_ptr 62 { 63 public: 64 // publish our template parameter and variations thereof 65 using element_type = _Tp; 66 using __pointer = add_pointer_t<_Tp>; // exposition-only 67 using __reference = add_lvalue_reference_t<_Tp>; // exposition-only 68 69 // 3.2.2, observer_ptr constructors 70 // default c'tor 71 constexpr observer_ptr() noexcept 72 : __t() 73 { } 74 75 // pointer-accepting c'tors 76 constexpr observer_ptr(nullptr_t) noexcept 77 : __t() 78 { } 79 80 constexpr explicit observer_ptr(__pointer __p) noexcept 81 : __t(__p) 82 { } 83 84 // copying c'tors (in addition to compiler-generated copy c'tor) 85 template <typename _Up, 86 typename = typename enable_if< 87 is_convertible<typename add_pointer<_Up>::type, __pointer 88 >::value 89 >::type> 90 constexpr observer_ptr(observer_ptr<_Up> __p) noexcept 91 : __t(__p.get()) 92 { 93 } 94 95 // 3.2.3, observer_ptr observers 96 constexpr __pointer 97 get() const noexcept 98 { 99 return __t; 100 } 101 102 constexpr __reference 103 operator*() const 104 { 105 return *get(); 106 } 107 108 constexpr __pointer 109 operator->() const noexcept 110 { 111 return get(); 112 } 113 114 constexpr explicit operator bool() const noexcept 115 { 116 return get() != nullptr; 117 } 118 119 // 3.2.4, observer_ptr conversions 120 constexpr explicit operator __pointer() const noexcept 121 { 122 return get(); 123 } 124 125 // 3.2.5, observer_ptr modifiers 126 constexpr __pointer 127 release() noexcept 128 { 129 __pointer __tmp = get(); 130 reset(); 131 return __tmp; 132 } 133 134 constexpr void 135 reset(__pointer __p = nullptr) noexcept 136 { 137 __t = __p; 138 } 139 140 constexpr void 141 swap(observer_ptr& __p) noexcept 142 { 143 std::swap(__t, __p.__t); 144 } 145 146 private: 147 __pointer __t; 148 }; // observer_ptr<> 149 150 template<typename _Tp> 151 void 152 swap(observer_ptr<_Tp>& __p1, observer_ptr<_Tp>& __p2) noexcept 153 { 154 __p1.swap(__p2); 155 } 156 157 template<typename _Tp> 158 observer_ptr<_Tp> 159 make_observer(_Tp* __p) noexcept 160 { 161 return observer_ptr<_Tp>(__p); 162 } 163 164 template<typename _Tp, typename _Up> 165 bool 166 operator==(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2) 167 { 168 return __p1.get() == __p2.get(); 169 } 170 171 template<typename _Tp, typename _Up> 172 bool 173 operator!=(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2) 174 { 175 return !(__p1 == __p2); 176 } 177 178 template<typename _Tp> 179 bool 180 operator==(observer_ptr<_Tp> __p, nullptr_t) noexcept 181 { 182 return !__p; 183 } 184 185 template<typename _Tp> 186 bool 187 operator==(nullptr_t, observer_ptr<_Tp> __p) noexcept 188 { 189 return !__p; 190 } 191 192 template<typename _Tp> 193 bool 194 operator!=(observer_ptr<_Tp> __p, nullptr_t) noexcept 195 { 196 return bool(__p); 197 } 198 199 template<typename _Tp> 200 bool 201 operator!=(nullptr_t, observer_ptr<_Tp> __p) noexcept 202 { 203 return bool(__p); 204 } 205 206 template<typename _Tp, typename _Up> 207 bool 208 operator<(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2) 209 { 210 return std::less<typename common_type<typename add_pointer<_Tp>::type, 211 typename add_pointer<_Up>::type 212 >::type 213 >{}(__p1.get(), __p2.get()); 214 } 215 216 template<typename _Tp, typename _Up> 217 bool 218 operator>(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2) 219 { 220 return __p2 < __p1; 221 } 222 223 template<typename _Tp, typename _Up> 224 bool 225 operator<=(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2) 226 { 227 return !(__p2 < __p1); 228 } 229 230 template<typename _Tp, typename _Up> 231 bool 232 operator>=(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2) 233 { 234 return !(__p1 < __p2); 235 } 236 } // namespace fundamentals_v2 237 } // namespace experimental 238 239 template <typename _Tp> 240 struct hash<experimental::observer_ptr<_Tp>> 241 { 242 using result_type = size_t; 243 using argument_type = experimental::observer_ptr<_Tp>; 244 245 size_t 246 operator()(const experimental::observer_ptr<_Tp>& __t) const 247 noexcept(noexcept(hash<typename add_pointer<_Tp>::type> {}(__t.get()))) 248 { 249 return hash<typename add_pointer<_Tp>::type> {}(__t.get()); 250 } 251 }; 252 253 254 _GLIBCXX_END_NAMESPACE_VERSION 255 } // namespace std 256 257 #endif // __cplusplus <= 201103L 258 259 #endif // _GLIBCXX_EXPERIMENTAL_MEMORY
