1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef _LIBCPP___FUNCTIONAL_MEM_FN_H 11 #define _LIBCPP___FUNCTIONAL_MEM_FN_H 12 13 #include <__config> 14 #include <__functional/binary_function.h> 15 #include <__functional/invoke.h> 16 #include <__functional/weak_result_type.h> 17 #include <__utility/forward.h> 18 #include <type_traits> 19 20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 21 # pragma GCC system_header 22 #endif 23 24 _LIBCPP_BEGIN_NAMESPACE_STD 25 26 template <class _Tp> 27 class __mem_fn : public __weak_result_type<_Tp> 28 { 29 public: 30 // types 31 typedef _Tp type; 32 private: 33 type __f_; 34 35 public: 36 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 37 __mem_fn(type __f) _NOEXCEPT : __f_(__f) {} 38 39 // invoke 40 template <class... _ArgTypes> 41 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 42 43 typename __invoke_return<type, _ArgTypes...>::type 44 operator() (_ArgTypes&&... __args) const { 45 return std::__invoke(__f_, std::forward<_ArgTypes>(__args)...); 46 } 47 }; 48 49 template<class _Rp, class _Tp> 50 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 51 __mem_fn<_Rp _Tp::*> 52 mem_fn(_Rp _Tp::* __pm) _NOEXCEPT 53 { 54 return __mem_fn<_Rp _Tp::*>(__pm); 55 } 56 57 _LIBCPP_END_NAMESPACE_STD 58 59 #endif // _LIBCPP___FUNCTIONAL_MEM_FN_H 60