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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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___CONCEPTS_INVOCABLE_H10#define _LIBCPP___CONCEPTS_INVOCABLE_H11 12#include <__config>13#include <__functional/invoke.h>14#include <__utility/forward.h>15 16#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)17# pragma GCC system_header18#endif19 20_LIBCPP_BEGIN_NAMESPACE_STD21 22#if _LIBCPP_STD_VER >= 2023 24// [concept.invocable]25 26template <class _Fn, class... _Args>27concept invocable = requires(_Fn&& __fn, _Args&&... __args) {28 std::invoke(std::forward<_Fn>(__fn), std::forward<_Args>(__args)...); // not required to be equality preserving29};30 31// [concept.regular.invocable]32 33template <class _Fn, class... _Args>34concept regular_invocable = invocable<_Fn, _Args...>;35 36#endif // _LIBCPP_STD_VER >= 2037 38_LIBCPP_END_NAMESPACE_STD39 40#endif // _LIBCPP___CONCEPTS_INVOCABLE_H41