1 //===----------------------------------------------------------------------===//
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
7 //===----------------------------------------------------------------------===//
9 #ifndef _LIBCPP___ALGORITHM_RANGES_MAX_H
10 #define _LIBCPP___ALGORITHM_RANGES_MAX_H
12 #include <__algorithm/ranges_min_element.h>
14 #include <__concepts/copyable.h>
16 #include <__functional/identity.h>
17 #include <__functional/invoke.h>
18 #include <__functional/ranges_operations.h>
19 #include <__iterator/concepts.h>
20 #include <__iterator/projected.h>
21 #include <__ranges/access.h>
22 #include <__ranges/concepts.h>
23 #include <__utility/move.h>
24 #include <initializer_list>
26 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
27 # pragma GCC system_header
30 #if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
33 #include <__undef_macros>
35 _LIBCPP_BEGIN_NAMESPACE_STD
40 template <class _Tp, class _Proj = identity,
41 indirect_strict_weak_order<projected<const _Tp*, _Proj>> _Comp = ranges::less>
42 _LIBCPP_HIDE_FROM_ABI constexpr
43 const _Tp& operator()(const _Tp& __a, const _Tp& __b, _Comp __comp = {}, _Proj __proj = {}) const {
44 return std::invoke(__comp, std::invoke(__proj, __a), std::invoke(__proj, __b)) ? __b : __a;
47 template <copyable _Tp, class _Proj = identity,
48 indirect_strict_weak_order<projected<const _Tp*, _Proj>> _Comp = ranges::less>
49 _LIBCPP_HIDE_FROM_ABI constexpr
50 _Tp operator()(initializer_list<_Tp> __il, _Comp __comp = {}, _Proj __proj = {}) const {
51 _LIBCPP_ASSERT(__il.begin() != __il.end(), "initializer_list must contain at least one element");
53 auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) { return std::invoke(__comp, __rhs, __lhs); };
54 return *ranges::__min_element_impl(__il.begin(), __il.end(), __comp_lhs_rhs_swapped, __proj);
57 template <input_range _Rp, class _Proj = identity,
58 indirect_strict_weak_order<projected<iterator_t<_Rp>, _Proj>> _Comp = ranges::less>
59 requires indirectly_copyable_storable<iterator_t<_Rp>, range_value_t<_Rp>*>
60 _LIBCPP_HIDE_FROM_ABI constexpr
61 range_value_t<_Rp> operator()(_Rp&& __r, _Comp __comp = {}, _Proj __proj = {}) const {
62 auto __first = ranges::begin(__r);
63 auto __last = ranges::end(__r);
65 _LIBCPP_ASSERT(__first != __last, "range must contain at least one element");
67 if constexpr (forward_range<_Rp>) {
68 auto __comp_lhs_rhs_swapped = [&](auto&& __lhs, auto&& __rhs) { return std::invoke(__comp, __rhs, __lhs); };
69 return *ranges::__min_element_impl(std::move(__first), std::move(__last), __comp_lhs_rhs_swapped, __proj);
71 range_value_t<_Rp> __result = *__first;
72 while (++__first != __last) {
73 if (std::invoke(__comp, std::invoke(__proj, __result), std::invoke(__proj, *__first)))
82 inline namespace __cpo {
83 inline constexpr auto max = __max::__fn{};
87 _LIBCPP_END_NAMESPACE_STD
91 #endif // _LIBCPP_STD_VER > 17 && && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
93 #endif // _LIBCPP___ALGORITHM_RANGES_MAX_H