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_DERIVED_FROM_H
10#define _LIBCPP___CONCEPTS_DERIVED_FROM_H
11
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_header
18#endif
19
20_LIBCPP_BEGIN_NAMESPACE_STD
21
22#if _LIBCPP_STD_VER >= 20
23
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 >= 20
30
31_LIBCPP_END_NAMESPACE_STD
32
33#endif // _LIBCPP___CONCEPTS_DERIVED_FROM_H
34