xref: /freebsd/contrib/llvm-project/libcxx/include/__algorithm/clamp.h (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
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___ALGORITHM_CLAMP_H
10 #define _LIBCPP___ALGORITHM_CLAMP_H
11 
12 #include <__algorithm/comp.h>
13 #include <__assert>
14 #include <__config>
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 >= 17
23 template <class _Tp, class _Compare>
24 [[nodiscard]] inline _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&
clamp(_LIBCPP_LIFETIMEBOUND const _Tp & __v,_LIBCPP_LIFETIMEBOUND const _Tp & __lo,_LIBCPP_LIFETIMEBOUND const _Tp & __hi,_Compare __comp)25 clamp(_LIBCPP_LIFETIMEBOUND const _Tp& __v,
26       _LIBCPP_LIFETIMEBOUND const _Tp& __lo,
27       _LIBCPP_LIFETIMEBOUND const _Tp& __hi,
28       _Compare __comp) {
29   _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
30   return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
31 }
32 
33 template <class _Tp>
34 [[nodiscard]] inline _LIBCPP_HIDE_FROM_ABI constexpr const _Tp&
clamp(_LIBCPP_LIFETIMEBOUND const _Tp & __v,_LIBCPP_LIFETIMEBOUND const _Tp & __lo,_LIBCPP_LIFETIMEBOUND const _Tp & __hi)35 clamp(_LIBCPP_LIFETIMEBOUND const _Tp& __v,
36       _LIBCPP_LIFETIMEBOUND const _Tp& __lo,
37       _LIBCPP_LIFETIMEBOUND const _Tp& __hi) {
38   return std::clamp(__v, __lo, __hi, __less<>());
39 }
40 #endif
41 
42 _LIBCPP_END_NAMESPACE_STD
43 
44 #endif // _LIBCPP___ALGORITHM_CLAMP_H
45