xref: /freebsd/contrib/llvm-project/libcxx/include/__type_traits/result_of.h (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef _LIBCPP___TYPE_TRAITS_RESULT_OF_H
10 #define _LIBCPP___TYPE_TRAITS_RESULT_OF_H
11 
12 #include <__config>
13 #include <__functional/invoke.h>
14 
15 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
16 #  pragma GCC system_header
17 #endif
18 
19 _LIBCPP_BEGIN_NAMESPACE_STD
20 
21 // result_of
22 
23 #if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_TYPE_TRAITS)
24 template <class _Callable>
25 class _LIBCPP_DEPRECATED_IN_CXX17 result_of;
26 
27 template <class _Fp, class... _Args>
28 class _LIBCPP_TEMPLATE_VIS result_of<_Fp(_Args...)> : public __invoke_of<_Fp, _Args...> {};
29 
30 #  if _LIBCPP_STD_VER >= 14
31 template <class _Tp>
32 using result_of_t _LIBCPP_DEPRECATED_IN_CXX17 = typename result_of<_Tp>::type;
33 #  endif // _LIBCPP_STD_VER >= 14
34 #endif   // _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_TYPE_TRAITS)
35 
36 _LIBCPP_END_NAMESPACE_STD
37 
38 #endif // _LIBCPP___TYPE_TRAITS_RESULT_OF_H
39