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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_BOOLEAN_TESTABLE_H10#define _LIBCPP___CONCEPTS_BOOLEAN_TESTABLE_H11 12#include <__concepts/convertible_to.h>13#include <__config>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// [concepts.booleantestable]25 26template <class _Tp>27concept __boolean_testable_impl = convertible_to<_Tp, bool>;28 29template <class _Tp>30concept __boolean_testable = __boolean_testable_impl<_Tp> && requires(_Tp&& __t) {31 { !std::forward<_Tp>(__t) } -> __boolean_testable_impl;32};33 34#endif // _LIBCPP_STD_VER >= 2035 36_LIBCPP_END_NAMESPACE_STD37 38#endif // _LIBCPP___CONCEPTS_BOOLEAN_TESTABLE_H39