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 _LIBCPP_PUSH_MACROS
  28 #include <__undef_macros>
  29
  30 #if _LIBCPP_STD_VER >= 20
  31
  32 _LIBCPP_BEGIN_NAMESPACE_STD
  33
  34 template <forward_iterator _Iterator, class _Data>
  35 class __iterator_with_data {
  36   _Iterator __iter_{};
  37   _Data __data_{};
  38
  39 public:
  40   using value_type      = iter_value_t<_Iterator>;
  41   using difference_type = iter_difference_t<_Iterator>;
  42
  43   _LIBCPP_HIDE_FROM_ABI __iterator_with_data() = default;
  44
  45   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data(_Iterator __iter, _Data __data)
  46       : __iter_(std::move(__iter)), __data_(std::move(__data)) {}
  47
  48   constexpr _LIBCPP_HIDE_FROM_ABI _Iterator __get_iter() const { return __iter_; }
  49
  50   constexpr _LIBCPP_HIDE_FROM_ABI _Data __get_data() && { return std::move(__data_); }
  51
  52   friend constexpr _LIBCPP_HIDE_FROM_ABI bool
  53   operator==(const __iterator_with_data& __lhs, const __iterator_with_data& __rhs) {
  54     return __lhs.__iter_ == __rhs.__iter_;
  55   }
  56
  57   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data& operator++() {
  58     ++__iter_;
  59     return *this;
  60   }
  61
  62   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data operator++(int) {
  63     auto __tmp = *this;
  64     __iter_++;
  65     return __tmp;
  66   }
  67
  68   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data& operator--()
  69     requires bidirectional_iterator<_Iterator>
  70   {
  71     --__iter_;
  72     return *this;
  73   }
  74
  75   constexpr _LIBCPP_HIDE_FROM_ABI __iterator_with_data operator--(int)
  76     requires bidirectional_iterator<_Iterator>
  77   {
  78     auto __tmp = *this;
  79     --__iter_;
  80     return __tmp;
  81   }
  82
  83   constexpr _LIBCPP_HIDE_FROM_ABI iter_reference_t<_Iterator> operator*() const { return *__iter_; }
  84
  85   _LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iterator>
  86   iter_move(const __iterator_with_data& __iter) noexcept(noexcept(ranges::iter_move(__iter.__iter_))) {
  87     return ranges::iter_move(__iter.__iter_);
  88   }
  89
  90   _LIBCPP_HIDE_FROM_ABI friend constexpr void
  91   iter_swap(const __iterator_with_data& __lhs,
  92             const __iterator_with_data& __rhs) noexcept(noexcept(ranges::iter_swap(__lhs.__iter_, __rhs.__iter_)))
  93     requires indirectly_swappable<_Iterator>
  94   {
  95     return ranges::iter_swap(__lhs.__data_, __rhs.__iter_);
  96   }
  97 };
  98
  99 _LIBCPP_END_NAMESPACE_STD
 100
 101 #endif // _LIBCPP_STD_VER >= 20
 102
 103 _LIBCPP_POP_MACROS
 104
 105 #endif // _LIBCPP___ITERATOR_ITERATOR_WITH_DATA_H