libcxx/include/__iterator/iterator_with_data.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___ITERATOR_ITERATOR_WITH_DATA_H
  10 #define _LIBCPP___ITERATOR_ITERATOR_WITH_DATA_H
  11
  12 #include <__compare/compare_three_way_result.h>
  13 #include <__compare/three_way_comparable.h>
  14 #include <__config>
  15 #include <__iterator/concepts.h>
  16 #include <__iterator/incrementable_traits.h>
  17 #include <__iterator/iter_move.h>
  18 #include <__iterator/iter_swap.h>
  19 #include <__iterator/iterator_traits.h>
  20 #include <__iterator/readable_traits.h>
  21 #include <__utility/move.h>
  22
  23 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  24 #  pragma GCC system_header
  25 #endif
  26
  27 #if _LIBCPP_STD_VER >= 20
  28
  29 _LIBCPP_BEGIN_NAMESPACE_STD
  30
  31 template <forward_iterator _Iterator, class _Data>
  32 class __iterator_with_data {
  33   _Iterator __iter_{};
  34   _Data __data_{};
  35
  36 public:
  37   using value_type      = iter_value_t<_Iterator>;
  38   using difference_type = iter_difference_t<_Iterator>;
  39
  40   _LIBCPP_HIDE_FROM_ABI __iterator_with_data() = default;
  41
  42   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data(_Iterator __iter, _Data __data)
  43       : __iter_(std::move(__iter)), __data_(std::move(__data)) {}
  44
  45   constexpr _LIBCPP_HIDE_FROM_ABI _Iterator __get_iter() const { return __iter_; }
  46
  47   constexpr _LIBCPP_HIDE_FROM_ABI _Data __get_data() && { return std::move(__data_); }
  48
  49   friend constexpr _LIBCPP_HIDE_FROM_ABI bool
  50   operator==(const __iterator_with_data& __lhs, const __iterator_with_data& __rhs) {
  51     return __lhs.__iter_ == __rhs.__iter_;
  52   }
  53
  54   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data& operator++() {
  55     ++__iter_;
  56     return *this;
  57   }
  58
  59   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data operator++(int) {
  60     auto __tmp = *this;
  61     __iter_++;
  62     return __tmp;
  63   }
  64
  65   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data& operator--()
  66     requires bidirectional_iterator<_Iterator>
  67   {
  68     --__iter_;
  69     return *this;
  70   }
  71
  72   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data operator--(int)
  73     requires bidirectional_iterator<_Iterator>
  74   {
  75     auto __tmp = *this;
  76     --__iter_;
  77     return __tmp;
  78   }
  79
  80   constexpr _LIBCPP_HIDE_FROM_ABI iter_reference_t<_Iterator> operator*() const { return *__iter_; }
  81
  82   _LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iterator>
  83   iter_move(const __iterator_with_data& __iter) noexcept(noexcept(ranges::iter_move(__iter.__iter_))) {
  84     return ranges::iter_move(__iter.__iter_);
  85   }
  86
  87   _LIBCPP_HIDE_FROM_ABI friend constexpr void
  88   iter_swap(const __iterator_with_data& __lhs,
  89             const __iterator_with_data& __rhs) noexcept(noexcept(ranges::iter_swap(__lhs.__iter_, __rhs.__iter_)))
  90     requires indirectly_swappable<_Iterator>
  91   {
  92     return ranges::iter_swap(__lhs.__data_, __rhs.__iter_);
  93   }
  94 };
  95
  96 _LIBCPP_END_NAMESPACE_STD
  97
  98 #endif // _LIBCPP_STD_VER >= 20
  99
 100 #endif // _LIBCPP___ITERATOR_ITERATOR_WITH_DATA_H