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 <__functional/identity.h>
16#include <__functional/invoke.h>
17#include <__iterator/iterator_traits.h>
18#include <__type_traits/is_callable.h>
19#include <__utility/move.h>
20
21#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
22#  pragma GCC system_header
23#endif
24
25_LIBCPP_PUSH_MACROS
26#include <__undef_macros>
27
28_LIBCPP_BEGIN_NAMESPACE_STD
29
30template <class _Comp, class _Iter, class _Sent, class _Proj>
31inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Iter
32__min_element(_Iter __first, _Sent __last, _Comp __comp, _Proj& __proj) {
33  if (__first == __last)
34    return __first;
35
36  _Iter __i = __first;
37  while (++__i != __last)
38    if (std::__invoke(__comp, std::__invoke(__proj, *__i), std::__invoke(__proj, *__first)))
39      __first = __i;
40
41  return __first;
42}
43
44template <class _Comp, class _Iter, class _Sent>
45_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Iter __min_element(_Iter __first, _Sent __last, _Comp __comp) {
46  auto __proj = __identity();
47  return std::__min_element<_Comp>(std::move(__first), std::move(__last), __comp, __proj);
48}
49
50template <class _ForwardIterator, class _Compare>
51_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
52min_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
53  static_assert(
54      __has_forward_iterator_category<_ForwardIterator>::value, "std::min_element requires a ForwardIterator");
55  static_assert(
56      __is_callable<_Compare, decltype(*__first), decltype(*__first)>::value, "The comparator has to be callable");
57
58  return std::__min_element<__comp_ref_type<_Compare> >(std::move(__first), std::move(__last), __comp);
59}
60
61template <class _ForwardIterator>
62_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
63min_element(_ForwardIterator __first, _ForwardIterator __last) {
64  return std::min_element(__first, __last, __less<>());
65}
66
67_LIBCPP_END_NAMESPACE_STD
68
69_LIBCPP_POP_MACROS
70
71#endif // _LIBCPP___ALGORITHM_MIN_ELEMENT_H
72