xref: /freebsd/contrib/llvm-project/libcxx/include/__functional/mem_fn.h (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1fe6060f1SDimitry Andric // -*- C++ -*-
2fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
3fe6060f1SDimitry Andric //
4fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
6fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7fe6060f1SDimitry Andric //
8fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
9fe6060f1SDimitry Andric 
10fe6060f1SDimitry Andric #ifndef _LIBCPP___FUNCTIONAL_MEM_FN_H
11fe6060f1SDimitry Andric #define _LIBCPP___FUNCTIONAL_MEM_FN_H
12fe6060f1SDimitry Andric 
13fe6060f1SDimitry Andric #include <__config>
14fe6060f1SDimitry Andric #include <__functional/binary_function.h>
15fe6060f1SDimitry Andric #include <__functional/invoke.h>
1604eeddc0SDimitry Andric #include <__functional/weak_result_type.h>
1781ad6265SDimitry Andric #include <__utility/forward.h>
18fe6060f1SDimitry Andric 
19fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
20fe6060f1SDimitry Andric #  pragma GCC system_header
21fe6060f1SDimitry Andric #endif
22fe6060f1SDimitry Andric 
23fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
24fe6060f1SDimitry Andric 
25fe6060f1SDimitry Andric template <class _Tp>
26*cb14a3feSDimitry Andric class __mem_fn : public __weak_result_type<_Tp> {
27fe6060f1SDimitry Andric public:
28fe6060f1SDimitry Andric   // types
29fe6060f1SDimitry Andric   typedef _Tp type;
30*cb14a3feSDimitry Andric 
31fe6060f1SDimitry Andric private:
32fe6060f1SDimitry Andric   type __f_;
33fe6060f1SDimitry Andric 
34fe6060f1SDimitry Andric public:
__mem_fn(type __f)35*cb14a3feSDimitry Andric   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __mem_fn(type __f) _NOEXCEPT : __f_(__f) {}
36fe6060f1SDimitry Andric 
37fe6060f1SDimitry Andric   // invoke
38fe6060f1SDimitry Andric   template <class... _ArgTypes>
395f757f3fSDimitry Andric   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
4081ad6265SDimitry Andric 
41fe6060f1SDimitry Andric   typename __invoke_return<type, _ArgTypes...>::type
operator()42fe6060f1SDimitry Andric   operator()(_ArgTypes&&... __args) const {
4381ad6265SDimitry Andric     return std::__invoke(__f_, std::forward<_ArgTypes>(__args)...);
44fe6060f1SDimitry Andric   }
45fe6060f1SDimitry Andric };
46fe6060f1SDimitry Andric 
47fe6060f1SDimitry Andric template <class _Rp, class _Tp>
mem_fn(_Rp _Tp::* __pm)48*cb14a3feSDimitry Andric inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __mem_fn<_Rp _Tp::*> mem_fn(_Rp _Tp::*__pm) _NOEXCEPT {
49fe6060f1SDimitry Andric   return __mem_fn<_Rp _Tp::*>(__pm);
50fe6060f1SDimitry Andric }
51fe6060f1SDimitry Andric 
52fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD
53fe6060f1SDimitry Andric 
54fe6060f1SDimitry Andric #endif // _LIBCPP___FUNCTIONAL_MEM_FN_H
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