xref: /freebsd/contrib/llvm-project/libcxx/include/__algorithm/minmax.h (revision 2e3507c25e42292b45a5482e116d278f5515d04d)
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_MINMAX_H
10 #define _LIBCPP___ALGORITHM_MINMAX_H
11 
12 #include <__algorithm/comp.h>
13 #include <__algorithm/minmax_element.h>
14 #include <__config>
15 #include <__functional/identity.h>
16 #include <__type_traits/is_callable.h>
17 #include <__utility/pair.h>
18 #include <initializer_list>
19 
20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21 #  pragma GCC system_header
22 #endif
23 
24 _LIBCPP_BEGIN_NAMESPACE_STD
25 
26 template<class _Tp, class _Compare>
27 _LIBCPP_NODISCARD_EXT inline
28 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
29 pair<const _Tp&, const _Tp&>
30 minmax(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b, _Compare __comp)
31 {
32     return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) :
33                               pair<const _Tp&, const _Tp&>(__a, __b);
34 }
35 
36 template<class _Tp>
37 _LIBCPP_NODISCARD_EXT inline
38 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
39 pair<const _Tp&, const _Tp&>
40 minmax(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b)
41 {
42     return std::minmax(__a, __b, __less<>());
43 }
44 
45 #ifndef _LIBCPP_CXX03_LANG
46 
47 template<class _Tp, class _Compare>
48 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
49 pair<_Tp, _Tp> minmax(initializer_list<_Tp> __t, _Compare __comp) {
50     static_assert(__is_callable<_Compare, _Tp, _Tp>::value, "The comparator has to be callable");
51     __identity __proj;
52     auto __ret = std::__minmax_element_impl(__t.begin(), __t.end(), __comp, __proj);
53     return pair<_Tp, _Tp>(*__ret.first, *__ret.second);
54 }
55 
56 template<class _Tp>
57 _LIBCPP_NODISCARD_EXT inline
58 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
59 pair<_Tp, _Tp>
60 minmax(initializer_list<_Tp> __t)
61 {
62     return std::minmax(__t, __less<>());
63 }
64 
65 #endif // _LIBCPP_CXX03_LANG
66 
67 _LIBCPP_END_NAMESPACE_STD
68 
69 #endif // _LIBCPP___ALGORITHM_MINMAX_H
70