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The C and C++ Include Header Files
cat -n /usr/include/c++/15/experimental/synchronized_value
1 // <experimental/synchronized_value> -*- C++ -*- 2 3 // Copyright The GNU Toolchain Authors. 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 include/experimental/synchronized_value 26 * This is a TS C++ Library header. 27 * @ingroup libfund-ts 28 */ 29 30 #ifndef _GLIBCXX_EXPERIMENTAL_SYNCVAL 31 #define _GLIBCXX_EXPERIMENTAL_SYNCVAL 1 32 33 #ifdef _GLIBCXX_SYSHDR 34 #pragma GCC system_header 35 #endif 36 37 #include <bits/requires_hosted.h> // for std::mutex 38 39 #if __cplusplus >= 201703L 40 #include <mutex> 41 #include <bits/invoke.h> 42 43 namespace std _GLIBCXX_VISIBILITY(default) 44 { 45 _GLIBCXX_BEGIN_NAMESPACE_VERSION 46 namespace experimental::inline concurrency_v2 47 { 48 #define __cpp_lib_concurrency_v2_synchronized_value 202302 49 50 template<typename _Tp> 51 class synchronized_value 52 { 53 // TODO: Use partial specialization after PR c++/71954 is fixed. 54 template<typename... _Args> 55 static inline constexpr bool __is_self 56 = sizeof...(_Args) == 1 57 && (is_same_v<__remove_cvref_t<_Args>, synchronized_value> && ...); 58 59 #if ! __cpp_concepts 60 template<typename... _Args> 61 using __not_self = bool_constant<!__is_self<_Args...>>; 62 #endif 63 64 public: 65 synchronized_value(const synchronized_value&) = delete; 66 synchronized_value& operator=(const synchronized_value&) = delete; 67 68 #if __cpp_concepts 69 template<typename... _Args> 70 requires (!__is_self<_Args...>) && is_constructible_v<_Tp, _Args...> 71 #else 72 template<typename... _Args, typename = _Require<__not_self<_Args...>>, 73 typename = _Require<is_constructible<_Tp, _Args...>>> 74 #endif 75 synchronized_value(_Args&&... __args) 76 noexcept(is_nothrow_constructible_v<_Tp, _Args...>) 77 : _M_val(std::forward<_Args>(__args)...) 78 { } 79 80 template<typename _Fn, typename _Up, typename ... _Types> 81 friend invoke_result_t<_Fn, _Up&, _Types&...> 82 apply(_Fn&&, synchronized_value<_Up>&, synchronized_value<_Types>&...); 83 84 private: 85 mutex _M_mut; 86 _Tp _M_val; 87 }; 88 89 template<typename _Fn, typename _Tp, typename... _Types> 90 inline invoke_result_t<_Fn, _Tp&, _Types&...> 91 apply(_Fn&& __f, synchronized_value<_Tp>& __val, 92 synchronized_value<_Types>&... __vals) 93 { 94 scoped_lock __l(__val._M_mut, __vals._M_mut...); 95 return std::__invoke(std::forward<_Fn>(__f), __val._M_val, 96 __vals._M_val...); 97 } 98 } // namespace experimental::concurrency_v2 99 _GLIBCXX_END_NAMESPACE_VERSION 100 } // namespace std 101 #endif // C++20 102 #endif // _GLIBCXX_EXPERIMENTAL_SYNCVAL
