xref: /llvm-project/libcxx/include/__algorithm/min_element.h (revision 5aaefa510ef055e8f044ca89e352d4313f3aba49)
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_MIN_ELEMENT_H
10 #define _LIBCPP___ALGORITHM_MIN_ELEMENT_H
11 
12 #include <__algorithm/comp.h>
13 #include <__algorithm/comp_ref_type.h>
14 #include <__config>
15 #include <__iterator/iterator_traits.h>
16 
17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18 #  pragma GCC system_header
19 #  pragma clang include_instead(<algorithm>)
20 #endif
21 
22 _LIBCPP_BEGIN_NAMESPACE_STD
23 
24 template <class _Compare, class _ForwardIterator>
25 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator
26 __min_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
27 {
28     static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
29         "std::min_element requires a ForwardIterator");
30     if (__first != __last)
31     {
32         _ForwardIterator __i = __first;
33         while (++__i != __last)
34             if (__comp(*__i, *__first))
35                 __first = __i;
36     }
37     return __first;
38 }
39 
40 template <class _ForwardIterator, class _Compare>
41 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator
42 min_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
43 {
44     typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
45     return _VSTD::__min_element<_Comp_ref>(__first, __last, __comp);
46 }
47 
48 template <class _ForwardIterator>
49 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator
50 min_element(_ForwardIterator __first, _ForwardIterator __last)
51 {
52     return _VSTD::min_element(__first, __last,
53               __less<typename iterator_traits<_ForwardIterator>::value_type>());
54 }
55 
56 _LIBCPP_END_NAMESPACE_STD
57 
58 #endif // _LIBCPP___ALGORITHM_MIN_ELEMENT_H
59