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___CONCEPTS_PREDICATE_H
10#define _LIBCPP___CONCEPTS_PREDICATE_H
11
12#include <__concepts/boolean_testable.h>
13#include <__concepts/invocable.h>
14#include <__config>
15#include <__type_traits/invoke.h>
16
17#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18# pragma GCC system_header
19#endif
20
21_LIBCPP_BEGIN_NAMESPACE_STD
22
23#if _LIBCPP_STD_VER >= 20
24
25// [concept.predicate]
26
27template <class _Fn, class... _Args>
28concept predicate = regular_invocable<_Fn, _Args...> && __boolean_testable<invoke_result_t<_Fn, _Args...>>;
29
30#endif // _LIBCPP_STD_VER >= 20
31
32_LIBCPP_END_NAMESPACE_STD
33
34#endif // _LIBCPP___CONCEPTS_PREDICATE_H
35