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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_DERIVED_FROM_H10#define _LIBCPP___CONCEPTS_DERIVED_FROM_H11 12#include <__config>13#include <__type_traits/is_base_of.h>14#include <__type_traits/is_convertible.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.derived]25 26template <class _Dp, class _Bp>27concept derived_from = is_base_of_v<_Bp, _Dp> && is_convertible_v<const volatile _Dp*, const volatile _Bp*>;28 29#endif // _LIBCPP_STD_VER >= 2030 31_LIBCPP_END_NAMESPACE_STD32 33#endif // _LIBCPP___CONCEPTS_DERIVED_FROM_H34