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___UTILITY_AS_CONST_H
10#define _LIBCPP___UTILITY_AS_CONST_H
11
12#include <__config>
13
14#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
15# pragma GCC system_header
16#endif
17
18_LIBCPP_BEGIN_NAMESPACE_STD
19
20#if _LIBCPP_STD_VER >= 17
21template <class _Tp>
22[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr const _Tp& as_const(_Tp& __t) noexcept {
23 return __t;
24}
25
26template <class _Tp>
27void as_const(const _Tp&&) = delete;
28#endif
29
30_LIBCPP_END_NAMESPACE_STD
31
32#endif // _LIBCPP___UTILITY_AS_CONST_H
33