libcxx/include/__algorithm/ranges_set_difference.h

   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_RANGES_SET_DIFFERENCE_H
  10 #define _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H
  11
  12 #include <__algorithm/in_out_result.h>
  13 #include <__algorithm/iterator_operations.h>
  14 #include <__algorithm/make_projected.h>
  15 #include <__algorithm/set_difference.h>
  16 #include <__config>
  17 #include <__functional/identity.h>
  18 #include <__functional/invoke.h>
  19 #include <__functional/ranges_operations.h>
  20 #include <__iterator/concepts.h>
  21 #include <__iterator/mergeable.h>
  22 #include <__ranges/access.h>
  23 #include <__ranges/concepts.h>
  24 #include <__ranges/dangling.h>
  25 #include <__type_traits/decay.h>
  26 #include <__utility/move.h>
  27 #include <__utility/pair.h>
  28
  29 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  30 #  pragma GCC system_header
  31 #endif
  32
  33 #if _LIBCPP_STD_VER >= 20
  34
  35 _LIBCPP_BEGIN_NAMESPACE_STD
  36
  37 namespace ranges {
  38
  39 template <class _InIter, class _OutIter>
  40 using set_difference_result = in_out_result<_InIter, _OutIter>;
  41
  42 namespace __set_difference {
  43
  44 struct __fn {
  45   template <input_iterator _InIter1,
  46             sentinel_for<_InIter1> _Sent1,
  47             input_iterator _InIter2,
  48             sentinel_for<_InIter2> _Sent2,
  49             weakly_incrementable _OutIter,
  50             class _Comp  = less,
  51             class _Proj1 = identity,
  52             class _Proj2 = identity>
  53     requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
  54   _LIBCPP_HIDE_FROM_ABI constexpr set_difference_result<_InIter1, _OutIter> operator()(
  55       _InIter1 __first1,
  56       _Sent1 __last1,
  57       _InIter2 __first2,
  58       _Sent2 __last2,
  59       _OutIter __result,
  60       _Comp __comp   = {},
  61       _Proj1 __proj1 = {},
  62       _Proj2 __proj2 = {}) const {
  63     auto __ret = std::__set_difference<_RangeAlgPolicy>(
  64         __first1, __last1, __first2, __last2, __result, ranges::__make_projected_comp(__comp, __proj1, __proj2));
  65     return {std::move(__ret.first), std::move(__ret.second)};
  66   }
  67
  68   template <input_range _Range1,
  69             input_range _Range2,
  70             weakly_incrementable _OutIter,
  71             class _Comp  = less,
  72             class _Proj1 = identity,
  73             class _Proj2 = identity>
  74     requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>
  75   _LIBCPP_HIDE_FROM_ABI constexpr set_difference_result<borrowed_iterator_t<_Range1>, _OutIter>
  76   operator()(_Range1&& __range1,
  77              _Range2&& __range2,
  78              _OutIter __result,
  79              _Comp __comp   = {},
  80              _Proj1 __proj1 = {},
  81              _Proj2 __proj2 = {}) const {
  82     auto __ret = std::__set_difference<_RangeAlgPolicy>(
  83         ranges::begin(__range1),
  84         ranges::end(__range1),
  85         ranges::begin(__range2),
  86         ranges::end(__range2),
  87         __result,
  88         ranges::__make_projected_comp(__comp, __proj1, __proj2));
  89     return {std::move(__ret.first), std::move(__ret.second)};
  90   }
  91 };
  92
  93 } // namespace __set_difference
  94
  95 inline namespace __cpo {
  96 inline constexpr auto set_difference = __set_difference::__fn{};
  97 } // namespace __cpo
  98 } // namespace ranges
  99
 100 _LIBCPP_END_NAMESPACE_STD
 101
 102 #endif // _LIBCPP_STD_VER >= 20
 103 #endif // _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H