xref: /freebsd/contrib/llvm-project/libcxx/include/iterator (revision 349cc55c9796c4596a5b9904cd3281af295f878f)
10b57cec5SDimitry Andric// -*- C++ -*-
2*349cc55cSDimitry Andric//===----------------------------------------------------------------------===//
30b57cec5SDimitry Andric//
40b57cec5SDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
50b57cec5SDimitry Andric// See https://llvm.org/LICENSE.txt for license information.
60b57cec5SDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
70b57cec5SDimitry Andric//
80b57cec5SDimitry Andric//===----------------------------------------------------------------------===//
90b57cec5SDimitry Andric
100b57cec5SDimitry Andric#ifndef _LIBCPP_ITERATOR
110b57cec5SDimitry Andric#define _LIBCPP_ITERATOR
120b57cec5SDimitry Andric
130b57cec5SDimitry Andric/*
140b57cec5SDimitry Andric    iterator synopsis
150b57cec5SDimitry Andric
16fe6060f1SDimitry Andric#include <concepts>
17fe6060f1SDimitry Andric
180b57cec5SDimitry Andricnamespace std
190b57cec5SDimitry Andric{
20fe6060f1SDimitry Andrictemplate<class> struct incrementable_traits;       // since C++20
21fe6060f1SDimitry Andrictemplate<class T>
22fe6060f1SDimitry Andric  using iter_difference_t = see below;             // since C++20
23fe6060f1SDimitry Andric
24fe6060f1SDimitry Andrictemplate<class> struct indirectly_readable_traits; // since C++20
25fe6060f1SDimitry Andrictemplate<class T>
26fe6060f1SDimitry Andric  using iter_value_t = see below;                  // since C++20
270b57cec5SDimitry Andric
280b57cec5SDimitry Andrictemplate<class Iterator>
29fe6060f1SDimitry Andricstruct iterator_traits;
300b57cec5SDimitry Andric
310b57cec5SDimitry Andrictemplate<class T>
32fe6060f1SDimitry Andric  requires is_object_v<T>                    // since C++20
33fe6060f1SDimitry Andricstruct iterator_traits<T*>;
34fe6060f1SDimitry Andric
35fe6060f1SDimitry Andrictemplate<dereferenceable T>
36fe6060f1SDimitry Andric  using iter_reference_t = decltype(*declval<T&>());
37fe6060f1SDimitry Andric
38fe6060f1SDimitry Andricnamespace ranges::inline unspecified {
39fe6060f1SDimitry Andric    inline constexpr unspecified iter_move = unspecified; // since C++20, nodiscard as an extension
40fe6060f1SDimitry Andric}}
41fe6060f1SDimitry Andric
42fe6060f1SDimitry Andrictemplate<dereferenceable T>
43fe6060f1SDimitry Andric  requires ...
44fe6060f1SDimitry Andricusing iter_rvalue_reference_t = decltype(ranges::iter_move(declval<T&>())); // since C++20
45fe6060f1SDimitry Andric
46fe6060f1SDimitry Andric// [iterator.concepts], iterator concepts
47fe6060f1SDimitry Andric// [iterator.concept.readable], concept indirectly_readable
48fe6060f1SDimitry Andrictemplate<class In>
49fe6060f1SDimitry Andric  concept indirectly_readable = see below;                      // since C++20
50fe6060f1SDimitry Andric
51fe6060f1SDimitry Andrictemplate<indirectly_readable T>
52fe6060f1SDimitry Andric  using iter_common_reference_t =
53fe6060f1SDimitry Andric    common_reference_t<iter_reference_t<T>, iter_value_t<T>&>;  // since C++20
54fe6060f1SDimitry Andric
55fe6060f1SDimitry Andric// [iterator.concept.writable], concept indirectly_writable
56fe6060f1SDimitry Andrictemplate<class Out, class T>
57fe6060f1SDimitry Andric  concept indirectly_writable = see below;                // since C++20
58fe6060f1SDimitry Andric
59fe6060f1SDimitry Andric// [iterator.concept.winc], concept weakly_incrementable
60fe6060f1SDimitry Andrictemplate<class I>
61fe6060f1SDimitry Andric  concept weakly_incrementable = see below;                // since C++20
62fe6060f1SDimitry Andric
63fe6060f1SDimitry Andric// [iterator.concept.inc], concept incrementable
64fe6060f1SDimitry Andrictemplate<class I>
65fe6060f1SDimitry Andric  concept incrementable = see below;                       // since C++20
66fe6060f1SDimitry Andric
67fe6060f1SDimitry Andric// [iterator.concept.iterator], concept input_or_output_iterator
68fe6060f1SDimitry Andric  template<class I>
69fe6060f1SDimitry Andric    concept input_or_output_iterator = see below;          // since C++20
70fe6060f1SDimitry Andric
71fe6060f1SDimitry Andric// [iterator.concept.sentinel], concept sentinel_for
72fe6060f1SDimitry Andrictemplate<class S, class I>
73fe6060f1SDimitry Andric  concept sentinel_for = see below;                        // since C++20
74fe6060f1SDimitry Andric
75fe6060f1SDimitry Andric// [iterator.concept.sizedsentinel], concept sized_sentinel_for
76fe6060f1SDimitry Andrictemplate<class S, class I>
77fe6060f1SDimitry Andric  inline constexpr bool disable_sized_sentinel_for = false;
78fe6060f1SDimitry Andric
79fe6060f1SDimitry Andrictemplate<class S, class I>
80fe6060f1SDimitry Andric  concept sized_sentinel_for = see below;
81fe6060f1SDimitry Andric
82fe6060f1SDimitry Andric// [iterator.concept.input], concept input_iterator
83fe6060f1SDimitry Andrictemplate<class I>
84fe6060f1SDimitry Andric  concept input_iterator = see below;                      // since C++20
85fe6060f1SDimitry Andric
86fe6060f1SDimitry Andric// [iterator.concept.output], concept output_iterator
87fe6060f1SDimitry Andrictemplate<class I, class T>
88fe6060f1SDimitry Andric  concept output_iterator = see below;                     // since C++20
89fe6060f1SDimitry Andric
90fe6060f1SDimitry Andric// [iterator.concept.forward], concept forward_iterator
91fe6060f1SDimitry Andrictemplate<class I>
92fe6060f1SDimitry Andric  concept forward_iterator = see below;                    // since C++20
93fe6060f1SDimitry Andric
94fe6060f1SDimitry Andric// [iterator.concept.bidir], concept bidirectional_iterator
95fe6060f1SDimitry Andrictemplate<class I>
96fe6060f1SDimitry Andric  concept bidirectional_iterator = see below;              // since C++20
97fe6060f1SDimitry Andric
98fe6060f1SDimitry Andric// [iterator.concept.random.access], concept random_access_iterator
99fe6060f1SDimitry Andrictemplate<class I>
100fe6060f1SDimitry Andric  concept random_access_iterator = see below;              // since C++20
101fe6060f1SDimitry Andric
102fe6060f1SDimitry Andric// [indirectcallable]
103fe6060f1SDimitry Andric// [indirectcallable.indirectinvocable]
104fe6060f1SDimitry Andrictemplate<class F, class I>
105fe6060f1SDimitry Andric  concept indirectly_unary_invocable = see below;          // since C++20
106fe6060f1SDimitry Andric
107fe6060f1SDimitry Andrictemplate<class F, class I>
108fe6060f1SDimitry Andric  concept indirectly_regular_unary_invocable = see below;  // since C++20
109fe6060f1SDimitry Andric
110fe6060f1SDimitry Andrictemplate<class F, class I>
111fe6060f1SDimitry Andric  concept indirect_unary_predicate = see below;            // since C++20
112fe6060f1SDimitry Andric
113fe6060f1SDimitry Andrictemplate<class F, class I1, class I2>
114fe6060f1SDimitry Andric  concept indirect_binary_predicate = see below;           // since C++20
115fe6060f1SDimitry Andric
116fe6060f1SDimitry Andrictemplate<class F, class I1, class I2 = I1>
117fe6060f1SDimitry Andric  concept indirect_equivalence_relation = see below;       // since C++20
118fe6060f1SDimitry Andric
119fe6060f1SDimitry Andrictemplate<class F, class I1, class I2 = I1>
120fe6060f1SDimitry Andric  concept indirect_strict_weak_order = see below;          // since C++20
121fe6060f1SDimitry Andric
122fe6060f1SDimitry Andrictemplate<class F, class... Is>
123fe6060f1SDimitry Andric  using indirect_result_t = see below;                     // since C++20
124fe6060f1SDimitry Andric
125fe6060f1SDimitry Andric// [projected], projected
126fe6060f1SDimitry Andrictemplate<indirectly_readable I, indirectly_regular_unary_invocable<I> Proj>
127fe6060f1SDimitry Andric  struct projected;                                        // since C++20
128fe6060f1SDimitry Andric
129fe6060f1SDimitry Andrictemplate<weakly_incrementable I, indirectly_regular_unary_invocable<I> Proj>
130fe6060f1SDimitry Andric  struct incrementable_traits<projected<I, Proj>>;         // since C++20
131fe6060f1SDimitry Andric
132fe6060f1SDimitry Andric// [alg.req.ind.move], concept indirectly_movable
133fe6060f1SDimitry Andrictemplate<class In, class Out>
134fe6060f1SDimitry Andric  concept indirectly_movable = see below;                  // since C++20
135fe6060f1SDimitry Andric
136fe6060f1SDimitry Andrictemplate<class In, class Out>
137fe6060f1SDimitry Andric  concept indirectly_movable_storable = see below;         // since C++20
138fe6060f1SDimitry Andric
139fe6060f1SDimitry Andric// [alg.req.ind.swap], concept indirectly_swappable
140fe6060f1SDimitry Andrictemplate<class I1, class I2 = I1>
141fe6060f1SDimitry Andric  concept indirectly_swappable = see below;                // since C++20
142fe6060f1SDimitry Andric
143fe6060f1SDimitry Andrictemplate<input_or_output_iterator I, sentinel_for<I> S>
144fe6060f1SDimitry Andric  requires (!same_as<I, S> && copyable<I>)
145fe6060f1SDimitry Andricclass common_iterator;                                     // since C++20
1460b57cec5SDimitry Andric
1470b57cec5SDimitry Andrictemplate<class Category, class T, class Distance = ptrdiff_t,
1480b57cec5SDimitry Andric         class Pointer = T*, class Reference = T&>
149fe6060f1SDimitry Andricstruct iterator                                            // deprecated in C++17
1500b57cec5SDimitry Andric{
1510b57cec5SDimitry Andric    typedef T         value_type;
1520b57cec5SDimitry Andric    typedef Distance  difference_type;
1530b57cec5SDimitry Andric    typedef Pointer   pointer;
1540b57cec5SDimitry Andric    typedef Reference reference;
1550b57cec5SDimitry Andric    typedef Category  iterator_category;
1560b57cec5SDimitry Andric};
1570b57cec5SDimitry Andric
1580b57cec5SDimitry Andricstruct input_iterator_tag  {};
1590b57cec5SDimitry Andricstruct output_iterator_tag {};
1600b57cec5SDimitry Andricstruct forward_iterator_tag       : public input_iterator_tag         {};
1610b57cec5SDimitry Andricstruct bidirectional_iterator_tag : public forward_iterator_tag       {};
1620b57cec5SDimitry Andricstruct random_access_iterator_tag : public bidirectional_iterator_tag {};
1630b57cec5SDimitry Andric
1640b57cec5SDimitry Andric// 27.4.3, iterator operations
1655ffd83dbSDimitry Andrictemplate <class InputIterator, class Distance>  // constexpr in C++17
1665ffd83dbSDimitry Andric  constexpr void advance(InputIterator& i, Distance n);
1670b57cec5SDimitry Andric
1680b57cec5SDimitry Andrictemplate <class InputIterator>  // constexpr in C++17
1690b57cec5SDimitry Andric  constexpr typename iterator_traits<InputIterator>::difference_type
1700b57cec5SDimitry Andric    distance(InputIterator first, InputIterator last);
1710b57cec5SDimitry Andric
1720b57cec5SDimitry Andrictemplate <class InputIterator>  // constexpr in C++17
1730b57cec5SDimitry Andric  constexpr InputIterator next(InputIterator x,
1740b57cec5SDimitry Andrictypename iterator_traits<InputIterator>::difference_type n = 1);
1750b57cec5SDimitry Andric
1760b57cec5SDimitry Andrictemplate <class BidirectionalIterator>  // constexpr in C++17
1770b57cec5SDimitry Andric  constexpr BidirectionalIterator prev(BidirectionalIterator x,
1780b57cec5SDimitry Andric    typename iterator_traits<BidirectionalIterator>::difference_type n = 1);
1790b57cec5SDimitry Andric
180fe6060f1SDimitry Andric// [range.iter.ops], range iterator operations
181fe6060f1SDimitry Andricnamespace ranges {
182fe6060f1SDimitry Andric  // [range.iter.op.advance], ranges::advance
183fe6060f1SDimitry Andric  template<input_or_output_iterator I>
184fe6060f1SDimitry Andric    constexpr void advance(I& i, iter_difference_t<I> n);                          // since C++20
185fe6060f1SDimitry Andric  template<input_or_output_iterator I, sentinel_for<I> S>
186fe6060f1SDimitry Andric    constexpr void advance(I& i, S bound);                                         // since C++20
187fe6060f1SDimitry Andric  template<input_or_output_iterator I, sentinel_for<I> S>
188fe6060f1SDimitry Andric    constexpr iter_difference_t<I> advance(I& i, iter_difference_t<I> n, S bound); // since C++20
189fe6060f1SDimitry Andric}
190fe6060f1SDimitry Andric
1910b57cec5SDimitry Andrictemplate <class Iterator>
1920b57cec5SDimitry Andricclass reverse_iterator
193fe6060f1SDimitry Andric    : public iterator<typename iterator_traits<Iterator>::iterator_category, // until C++17
1940b57cec5SDimitry Andric                      typename iterator_traits<Iterator>::value_type,
1950b57cec5SDimitry Andric                      typename iterator_traits<Iterator>::difference_type,
1960b57cec5SDimitry Andric                      typename iterator_traits<Iterator>::pointer,
1970b57cec5SDimitry Andric                      typename iterator_traits<Iterator>::reference>
1980b57cec5SDimitry Andric{
1990b57cec5SDimitry Andricprotected:
2000b57cec5SDimitry Andric    Iterator current;
2010b57cec5SDimitry Andricpublic:
2020b57cec5SDimitry Andric    typedef Iterator                                            iterator_type;
2030b57cec5SDimitry Andric    typedef typename iterator_traits<Iterator>::difference_type difference_type;
2040b57cec5SDimitry Andric    typedef typename iterator_traits<Iterator>::reference       reference;
2050b57cec5SDimitry Andric    typedef typename iterator_traits<Iterator>::pointer         pointer;
2060b57cec5SDimitry Andric
2070b57cec5SDimitry Andric    constexpr reverse_iterator();
2080b57cec5SDimitry Andric    constexpr explicit reverse_iterator(Iterator x);
2090b57cec5SDimitry Andric    template <class U> constexpr reverse_iterator(const reverse_iterator<U>& u);
2100b57cec5SDimitry Andric    template <class U> constexpr reverse_iterator& operator=(const reverse_iterator<U>& u);
2110b57cec5SDimitry Andric    constexpr Iterator base() const;
2120b57cec5SDimitry Andric    constexpr reference operator*() const;
2130b57cec5SDimitry Andric    constexpr pointer   operator->() const;
2140b57cec5SDimitry Andric    constexpr reverse_iterator& operator++();
2150b57cec5SDimitry Andric    constexpr reverse_iterator  operator++(int);
2160b57cec5SDimitry Andric    constexpr reverse_iterator& operator--();
2170b57cec5SDimitry Andric    constexpr reverse_iterator  operator--(int);
2180b57cec5SDimitry Andric    constexpr reverse_iterator  operator+ (difference_type n) const;
2190b57cec5SDimitry Andric    constexpr reverse_iterator& operator+=(difference_type n);
2200b57cec5SDimitry Andric    constexpr reverse_iterator  operator- (difference_type n) const;
2210b57cec5SDimitry Andric    constexpr reverse_iterator& operator-=(difference_type n);
2220b57cec5SDimitry Andric    constexpr reference         operator[](difference_type n) const;
2230b57cec5SDimitry Andric};
2240b57cec5SDimitry Andric
2250b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
2260b57cec5SDimitry Andricconstexpr bool                          // constexpr in C++17
2270b57cec5SDimitry Andricoperator==(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
2280b57cec5SDimitry Andric
2290b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
2300b57cec5SDimitry Andricconstexpr bool                          // constexpr in C++17
2310b57cec5SDimitry Andricoperator<(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
2320b57cec5SDimitry Andric
2330b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
2340b57cec5SDimitry Andricconstexpr bool                          // constexpr in C++17
2350b57cec5SDimitry Andricoperator!=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
2360b57cec5SDimitry Andric
2370b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
2380b57cec5SDimitry Andricconstexpr bool                          // constexpr in C++17
2390b57cec5SDimitry Andricoperator>(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
2400b57cec5SDimitry Andric
2410b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
2420b57cec5SDimitry Andricconstexpr bool                          // constexpr in C++17
2430b57cec5SDimitry Andricoperator>=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
2440b57cec5SDimitry Andric
2450b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
2460b57cec5SDimitry Andricconstexpr bool                          // constexpr in C++17
2470b57cec5SDimitry Andricoperator<=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
2480b57cec5SDimitry Andric
2490b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
2500b57cec5SDimitry Andricconstexpr auto
2510b57cec5SDimitry Andricoperator-(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y)
2520b57cec5SDimitry Andric-> decltype(__y.base() - __x.base());   // constexpr in C++17
2530b57cec5SDimitry Andric
2540b57cec5SDimitry Andrictemplate <class Iterator>
2550b57cec5SDimitry Andricconstexpr reverse_iterator<Iterator>
2560b57cec5SDimitry Andricoperator+(typename reverse_iterator<Iterator>::difference_type n,
2570b57cec5SDimitry Andric          const reverse_iterator<Iterator>& x);   // constexpr in C++17
2580b57cec5SDimitry Andric
2590b57cec5SDimitry Andrictemplate <class Iterator>
2600b57cec5SDimitry Andricconstexpr reverse_iterator<Iterator> make_reverse_iterator(Iterator i); // C++14, constexpr in C++17
2610b57cec5SDimitry Andric
2620b57cec5SDimitry Andrictemplate <class Container>
2630b57cec5SDimitry Andricclass back_insert_iterator
264fe6060f1SDimitry Andric    : public iterator<output_iterator_tag, void, void, void, void> // until C++17
2650b57cec5SDimitry Andric{
2660b57cec5SDimitry Andricprotected:
2670b57cec5SDimitry Andric    Container* container;
2680b57cec5SDimitry Andricpublic:
2690b57cec5SDimitry Andric    typedef Container                   container_type;
2700b57cec5SDimitry Andric    typedef void                        value_type;
271fe6060f1SDimitry Andric    typedef void                        difference_type; // until C++20
272fe6060f1SDimitry Andric    typedef ptrdiff_t                   difference_type; // since C++20
2730b57cec5SDimitry Andric    typedef void                        reference;
2740b57cec5SDimitry Andric    typedef void                        pointer;
2750b57cec5SDimitry Andric
276fe6060f1SDimitry Andric    explicit back_insert_iterator(Container& x);  // constexpr in C++20
277fe6060f1SDimitry Andric    back_insert_iterator& operator=(const typename Container::value_type& value);  // constexpr in C++20
278fe6060f1SDimitry Andric    back_insert_iterator& operator*();  // constexpr in C++20
279fe6060f1SDimitry Andric    back_insert_iterator& operator++();  // constexpr in C++20
280fe6060f1SDimitry Andric    back_insert_iterator  operator++(int);  // constexpr in C++20
2810b57cec5SDimitry Andric};
2820b57cec5SDimitry Andric
283fe6060f1SDimitry Andrictemplate <class Container> back_insert_iterator<Container> back_inserter(Container& x);  // constexpr in C++20
2840b57cec5SDimitry Andric
2850b57cec5SDimitry Andrictemplate <class Container>
2860b57cec5SDimitry Andricclass front_insert_iterator
287fe6060f1SDimitry Andric    : public iterator<output_iterator_tag, void, void, void, void> // until C++17
2880b57cec5SDimitry Andric{
2890b57cec5SDimitry Andricprotected:
2900b57cec5SDimitry Andric    Container* container;
2910b57cec5SDimitry Andricpublic:
2920b57cec5SDimitry Andric    typedef Container                    container_type;
2930b57cec5SDimitry Andric    typedef void                         value_type;
294fe6060f1SDimitry Andric    typedef void                         difference_type; // until C++20
295fe6060f1SDimitry Andric    typedef ptrdiff_t                    difference_type; // since C++20
2960b57cec5SDimitry Andric    typedef void                         reference;
2970b57cec5SDimitry Andric    typedef void                         pointer;
2980b57cec5SDimitry Andric
299fe6060f1SDimitry Andric    explicit front_insert_iterator(Container& x);  // constexpr in C++20
300fe6060f1SDimitry Andric    front_insert_iterator& operator=(const typename Container::value_type& value);  // constexpr in C++20
301fe6060f1SDimitry Andric    front_insert_iterator& operator*();  // constexpr in C++20
302fe6060f1SDimitry Andric    front_insert_iterator& operator++();  // constexpr in C++20
303fe6060f1SDimitry Andric    front_insert_iterator  operator++(int);  // constexpr in C++20
3040b57cec5SDimitry Andric};
3050b57cec5SDimitry Andric
306fe6060f1SDimitry Andrictemplate <class Container> front_insert_iterator<Container> front_inserter(Container& x);  // constexpr in C++20
3070b57cec5SDimitry Andric
3080b57cec5SDimitry Andrictemplate <class Container>
3090b57cec5SDimitry Andricclass insert_iterator
310fe6060f1SDimitry Andric    : public iterator<output_iterator_tag, void, void, void, void> // until C++17
3110b57cec5SDimitry Andric{
3120b57cec5SDimitry Andricprotected:
3130b57cec5SDimitry Andric    Container* container;
3140b57cec5SDimitry Andric    typename Container::iterator iter;
3150b57cec5SDimitry Andricpublic:
3160b57cec5SDimitry Andric    typedef Container              container_type;
3170b57cec5SDimitry Andric    typedef void                   value_type;
318fe6060f1SDimitry Andric    typedef void                   difference_type; // until C++20
319fe6060f1SDimitry Andric    typedef ptrdiff_t              difference_type; // since C++20
3200b57cec5SDimitry Andric    typedef void                   reference;
3210b57cec5SDimitry Andric    typedef void                   pointer;
3220b57cec5SDimitry Andric
323fe6060f1SDimitry Andric    insert_iterator(Container& x, typename Container::iterator i);  // constexpr in C++20
324fe6060f1SDimitry Andric    insert_iterator& operator=(const typename Container::value_type& value);  // constexpr in C++20
325fe6060f1SDimitry Andric    insert_iterator& operator*();  // constexpr in C++20
326fe6060f1SDimitry Andric    insert_iterator& operator++();  // constexpr in C++20
327fe6060f1SDimitry Andric    insert_iterator& operator++(int);  // constexpr in C++20
3280b57cec5SDimitry Andric};
3290b57cec5SDimitry Andric
3300b57cec5SDimitry Andrictemplate <class Container, class Iterator>
331fe6060f1SDimitry Andricinsert_iterator<Container> inserter(Container& x, Iterator i);  // constexpr in C++20
3320b57cec5SDimitry Andric
3330b57cec5SDimitry Andrictemplate <class Iterator>
3340b57cec5SDimitry Andricclass move_iterator {
3350b57cec5SDimitry Andricpublic:
3360b57cec5SDimitry Andric    typedef Iterator                                              iterator_type;
3370b57cec5SDimitry Andric    typedef typename iterator_traits<Iterator>::difference_type   difference_type;
3380b57cec5SDimitry Andric    typedef Iterator                                              pointer;
3390b57cec5SDimitry Andric    typedef typename iterator_traits<Iterator>::value_type        value_type;
3400b57cec5SDimitry Andric    typedef typename iterator_traits<Iterator>::iterator_category iterator_category;
3410b57cec5SDimitry Andric    typedef value_type&&                                          reference;
3420b57cec5SDimitry Andric
3430b57cec5SDimitry Andric    constexpr move_iterator();  // all the constexprs are in C++17
3440b57cec5SDimitry Andric    constexpr explicit move_iterator(Iterator i);
3450b57cec5SDimitry Andric    template <class U>
3460b57cec5SDimitry Andric      constexpr move_iterator(const move_iterator<U>& u);
3470b57cec5SDimitry Andric    template <class U>
3480b57cec5SDimitry Andric      constexpr move_iterator& operator=(const move_iterator<U>& u);
3490b57cec5SDimitry Andric    constexpr iterator_type base() const;
3500b57cec5SDimitry Andric    constexpr reference operator*() const;
3510b57cec5SDimitry Andric    constexpr pointer operator->() const;
3520b57cec5SDimitry Andric    constexpr move_iterator& operator++();
3530b57cec5SDimitry Andric    constexpr move_iterator operator++(int);
3540b57cec5SDimitry Andric    constexpr move_iterator& operator--();
3550b57cec5SDimitry Andric    constexpr move_iterator operator--(int);
3560b57cec5SDimitry Andric    constexpr move_iterator operator+(difference_type n) const;
3570b57cec5SDimitry Andric    constexpr move_iterator& operator+=(difference_type n);
3580b57cec5SDimitry Andric    constexpr move_iterator operator-(difference_type n) const;
3590b57cec5SDimitry Andric    constexpr move_iterator& operator-=(difference_type n);
3600b57cec5SDimitry Andric    constexpr unspecified operator[](difference_type n) const;
3610b57cec5SDimitry Andricprivate:
3620b57cec5SDimitry Andric    Iterator current; // exposition only
3630b57cec5SDimitry Andric};
3640b57cec5SDimitry Andric
3650b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
3660b57cec5SDimitry Andricconstexpr bool   // constexpr in C++17
3670b57cec5SDimitry Andricoperator==(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
3680b57cec5SDimitry Andric
3690b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
3700b57cec5SDimitry Andricconstexpr bool   // constexpr in C++17
3710b57cec5SDimitry Andricoperator!=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
3720b57cec5SDimitry Andric
3730b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
3740b57cec5SDimitry Andricconstexpr bool   // constexpr in C++17
3750b57cec5SDimitry Andricoperator<(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
3760b57cec5SDimitry Andric
3770b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
3780b57cec5SDimitry Andricconstexpr bool   // constexpr in C++17
3790b57cec5SDimitry Andricoperator<=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
3800b57cec5SDimitry Andric
3810b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
3820b57cec5SDimitry Andricconstexpr bool   // constexpr in C++17
3830b57cec5SDimitry Andricoperator>(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
3840b57cec5SDimitry Andric
3850b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
3860b57cec5SDimitry Andricconstexpr bool   // constexpr in C++17
3870b57cec5SDimitry Andricoperator>=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
3880b57cec5SDimitry Andric
3890b57cec5SDimitry Andrictemplate <class Iterator1, class Iterator2>
3900b57cec5SDimitry Andricconstexpr auto   // constexpr in C++17
3910b57cec5SDimitry Andricoperator-(const move_iterator<Iterator1>& x,
3920b57cec5SDimitry Andric          const move_iterator<Iterator2>& y) -> decltype(x.base() - y.base());
3930b57cec5SDimitry Andric
3940b57cec5SDimitry Andrictemplate <class Iterator>
3950b57cec5SDimitry Andricconstexpr move_iterator<Iterator> operator+(   // constexpr in C++17
3960b57cec5SDimitry Andric            typename move_iterator<Iterator>::difference_type n,
3970b57cec5SDimitry Andric            const move_iterator<Iterator>& x);
3980b57cec5SDimitry Andric
3990b57cec5SDimitry Andrictemplate <class Iterator>   // constexpr in C++17
4000b57cec5SDimitry Andricconstexpr  move_iterator<Iterator> make_move_iterator(const Iterator& i);
4010b57cec5SDimitry Andric
402fe6060f1SDimitry Andric// [default.sentinel], default sentinel
403fe6060f1SDimitry Andricstruct default_sentinel_t;
404fe6060f1SDimitry Andricinline constexpr default_sentinel_t default_sentinel{};
405fe6060f1SDimitry Andric
406fe6060f1SDimitry Andric// [iterators.counted], counted iterators
407fe6060f1SDimitry Andrictemplate<input_or_output_iterator I> class counted_iterator;
408fe6060f1SDimitry Andric
409fe6060f1SDimitry Andrictemplate<input_iterator I>
410fe6060f1SDimitry Andric  requires see below
411fe6060f1SDimitry Andric  struct iterator_traits<counted_iterator<I>>;
4120b57cec5SDimitry Andric
413*349cc55cSDimitry Andric// [unreachable.sentinel], unreachable sentinel
414*349cc55cSDimitry Andricstruct unreachable_sentinel_t;
415*349cc55cSDimitry Andricinline constexpr unreachable_sentinel_t unreachable_sentinel{};
416*349cc55cSDimitry Andric
4170b57cec5SDimitry Andrictemplate <class T, class charT = char, class traits = char_traits<charT>, class Distance = ptrdiff_t>
4180b57cec5SDimitry Andricclass istream_iterator
419fe6060f1SDimitry Andric    : public iterator<input_iterator_tag, T, Distance, const T*, const T&> // until C++17
4200b57cec5SDimitry Andric{
4210b57cec5SDimitry Andricpublic:
422fe6060f1SDimitry Andric    typedef input_iterator_tag           iterator_category;
423fe6060f1SDimitry Andric    typedef T                            value_type;
424fe6060f1SDimitry Andric    typedef Distance                     difference_type;
425fe6060f1SDimitry Andric    typedef const T*                     pointer;
426fe6060f1SDimitry Andric    typedef const T&                     reference;
427fe6060f1SDimitry Andric
4280b57cec5SDimitry Andric    typedef charT                        char_type;
4290b57cec5SDimitry Andric    typedef traits                       traits_type;
4300b57cec5SDimitry Andric    typedef basic_istream<charT, traits> istream_type;
4310b57cec5SDimitry Andric
4320b57cec5SDimitry Andric    constexpr istream_iterator();
4330b57cec5SDimitry Andric    istream_iterator(istream_type& s);
4340b57cec5SDimitry Andric    istream_iterator(const istream_iterator& x);
4350b57cec5SDimitry Andric    ~istream_iterator();
4360b57cec5SDimitry Andric
4370b57cec5SDimitry Andric    const T& operator*() const;
4380b57cec5SDimitry Andric    const T* operator->() const;
4390b57cec5SDimitry Andric    istream_iterator& operator++();
4400b57cec5SDimitry Andric    istream_iterator  operator++(int);
4410b57cec5SDimitry Andric};
4420b57cec5SDimitry Andric
4430b57cec5SDimitry Andrictemplate <class T, class charT, class traits, class Distance>
4440b57cec5SDimitry Andricbool operator==(const istream_iterator<T,charT,traits,Distance>& x,
4450b57cec5SDimitry Andric                const istream_iterator<T,charT,traits,Distance>& y);
4460b57cec5SDimitry Andrictemplate <class T, class charT, class traits, class Distance>
4470b57cec5SDimitry Andricbool operator!=(const istream_iterator<T,charT,traits,Distance>& x,
4480b57cec5SDimitry Andric                const istream_iterator<T,charT,traits,Distance>& y);
4490b57cec5SDimitry Andric
4500b57cec5SDimitry Andrictemplate <class T, class charT = char, class traits = char_traits<charT> >
4510b57cec5SDimitry Andricclass ostream_iterator
452fe6060f1SDimitry Andric    : public iterator<output_iterator_tag, void, void, void, void> // until C++17
4530b57cec5SDimitry Andric{
4540b57cec5SDimitry Andricpublic:
455fe6060f1SDimitry Andric    typedef output_iterator_tag         iterator_category;
456fe6060f1SDimitry Andric    typedef void                        value_type;
457fe6060f1SDimitry Andric    typedef void                        difference_type; // until C++20
458fe6060f1SDimitry Andric    typedef ptrdiff_t                   difference_type; // since C++20
459fe6060f1SDimitry Andric    typedef void                        pointer;
460fe6060f1SDimitry Andric    typedef void                        reference;
461fe6060f1SDimitry Andric
4620b57cec5SDimitry Andric    typedef charT char_type;
4630b57cec5SDimitry Andric    typedef traits traits_type;
4640b57cec5SDimitry Andric    typedef basic_ostream<charT,traits> ostream_type;
4650b57cec5SDimitry Andric
4660b57cec5SDimitry Andric    ostream_iterator(ostream_type& s);
4670b57cec5SDimitry Andric    ostream_iterator(ostream_type& s, const charT* delimiter);
4680b57cec5SDimitry Andric    ostream_iterator(const ostream_iterator& x);
4690b57cec5SDimitry Andric    ~ostream_iterator();
4700b57cec5SDimitry Andric    ostream_iterator& operator=(const T& value);
4710b57cec5SDimitry Andric
4720b57cec5SDimitry Andric    ostream_iterator& operator*();
4730b57cec5SDimitry Andric    ostream_iterator& operator++();
4740b57cec5SDimitry Andric    ostream_iterator& operator++(int);
4750b57cec5SDimitry Andric};
4760b57cec5SDimitry Andric
4770b57cec5SDimitry Andrictemplate<class charT, class traits = char_traits<charT> >
4780b57cec5SDimitry Andricclass istreambuf_iterator
479fe6060f1SDimitry Andric    : public iterator<input_iterator_tag, charT, traits::off_type, unspecified, charT> // until C++17
4800b57cec5SDimitry Andric{
4810b57cec5SDimitry Andricpublic:
482fe6060f1SDimitry Andric    typedef input_iterator_tag              iterator_category;
483fe6060f1SDimitry Andric    typedef charT                           value_type;
484fe6060f1SDimitry Andric    typedef traits::off_type                difference_type;
485fe6060f1SDimitry Andric    typedef unspecified                     pointer;
486fe6060f1SDimitry Andric    typedef charT                           reference;
487fe6060f1SDimitry Andric
4880b57cec5SDimitry Andric    typedef charT                           char_type;
4890b57cec5SDimitry Andric    typedef traits                          traits_type;
490fe6060f1SDimitry Andric    typedef traits::int_type                int_type;
4910b57cec5SDimitry Andric    typedef basic_streambuf<charT, traits>  streambuf_type;
4920b57cec5SDimitry Andric    typedef basic_istream<charT, traits>    istream_type;
4930b57cec5SDimitry Andric
4940b57cec5SDimitry Andric    istreambuf_iterator() noexcept;
4950b57cec5SDimitry Andric    istreambuf_iterator(istream_type& s) noexcept;
4960b57cec5SDimitry Andric    istreambuf_iterator(streambuf_type* s) noexcept;
4970b57cec5SDimitry Andric    istreambuf_iterator(a-private-type) noexcept;
4980b57cec5SDimitry Andric
4990b57cec5SDimitry Andric    charT                operator*() const;
5000b57cec5SDimitry Andric    pointer operator->() const;
5010b57cec5SDimitry Andric    istreambuf_iterator& operator++();
5020b57cec5SDimitry Andric    a-private-type       operator++(int);
5030b57cec5SDimitry Andric
5040b57cec5SDimitry Andric    bool equal(const istreambuf_iterator& b) const;
5050b57cec5SDimitry Andric};
5060b57cec5SDimitry Andric
5070b57cec5SDimitry Andrictemplate <class charT, class traits>
5080b57cec5SDimitry Andricbool operator==(const istreambuf_iterator<charT,traits>& a,
5090b57cec5SDimitry Andric                const istreambuf_iterator<charT,traits>& b);
5100b57cec5SDimitry Andrictemplate <class charT, class traits>
5110b57cec5SDimitry Andricbool operator!=(const istreambuf_iterator<charT,traits>& a,
5120b57cec5SDimitry Andric                const istreambuf_iterator<charT,traits>& b);
5130b57cec5SDimitry Andric
5140b57cec5SDimitry Andrictemplate <class charT, class traits = char_traits<charT> >
5150b57cec5SDimitry Andricclass ostreambuf_iterator
516fe6060f1SDimitry Andric    : public iterator<output_iterator_tag, void, void, void, void> // until C++17
5170b57cec5SDimitry Andric{
5180b57cec5SDimitry Andricpublic:
519fe6060f1SDimitry Andric    typedef output_iterator_tag            iterator_category;
520fe6060f1SDimitry Andric    typedef void                           value_type;
521fe6060f1SDimitry Andric    typedef void                           difference_type; // until C++20
522fe6060f1SDimitry Andric    typedef ptrdiff_t                      difference_type; // since C++20
523fe6060f1SDimitry Andric    typedef void                           pointer;
524fe6060f1SDimitry Andric    typedef void                           reference;
525fe6060f1SDimitry Andric
5260b57cec5SDimitry Andric    typedef charT                          char_type;
5270b57cec5SDimitry Andric    typedef traits                         traits_type;
5280b57cec5SDimitry Andric    typedef basic_streambuf<charT, traits> streambuf_type;
5290b57cec5SDimitry Andric    typedef basic_ostream<charT, traits>   ostream_type;
5300b57cec5SDimitry Andric
5310b57cec5SDimitry Andric    ostreambuf_iterator(ostream_type& s) noexcept;
5320b57cec5SDimitry Andric    ostreambuf_iterator(streambuf_type* s) noexcept;
5330b57cec5SDimitry Andric    ostreambuf_iterator& operator=(charT c);
5340b57cec5SDimitry Andric    ostreambuf_iterator& operator*();
5350b57cec5SDimitry Andric    ostreambuf_iterator& operator++();
5360b57cec5SDimitry Andric    ostreambuf_iterator& operator++(int);
5370b57cec5SDimitry Andric    bool failed() const noexcept;
5380b57cec5SDimitry Andric};
5390b57cec5SDimitry Andric
5400b57cec5SDimitry Andrictemplate <class C> constexpr auto begin(C& c) -> decltype(c.begin());
5410b57cec5SDimitry Andrictemplate <class C> constexpr auto begin(const C& c) -> decltype(c.begin());
5420b57cec5SDimitry Andrictemplate <class C> constexpr auto end(C& c) -> decltype(c.end());
5430b57cec5SDimitry Andrictemplate <class C> constexpr auto end(const C& c) -> decltype(c.end());
5440b57cec5SDimitry Andrictemplate <class T, size_t N> constexpr T* begin(T (&array)[N]);
5450b57cec5SDimitry Andrictemplate <class T, size_t N> constexpr T* end(T (&array)[N]);
5460b57cec5SDimitry Andric
5470b57cec5SDimitry Andrictemplate <class C> auto constexpr cbegin(const C& c) -> decltype(std::begin(c));        // C++14
5480b57cec5SDimitry Andrictemplate <class C> auto constexpr cend(const C& c) -> decltype(std::end(c));            // C++14
5490b57cec5SDimitry Andrictemplate <class C> auto constexpr rbegin(C& c) -> decltype(c.rbegin());                 // C++14
5500b57cec5SDimitry Andrictemplate <class C> auto constexpr rbegin(const C& c) -> decltype(c.rbegin());           // C++14
5510b57cec5SDimitry Andrictemplate <class C> auto constexpr rend(C& c) -> decltype(c.rend());                     // C++14
5520b57cec5SDimitry Andrictemplate <class C> constexpr auto rend(const C& c) -> decltype(c.rend());               // C++14
5530b57cec5SDimitry Andrictemplate <class E> reverse_iterator<const E*> constexpr rbegin(initializer_list<E> il); // C++14
5540b57cec5SDimitry Andrictemplate <class E> reverse_iterator<const E*> constexpr rend(initializer_list<E> il);   // C++14
5550b57cec5SDimitry Andrictemplate <class T, size_t N> reverse_iterator<T*> constexpr rbegin(T (&array)[N]);      // C++14
5560b57cec5SDimitry Andrictemplate <class T, size_t N> reverse_iterator<T*> constexpr rend(T (&array)[N]);        // C++14
5570b57cec5SDimitry Andrictemplate <class C> constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c));      // C++14
5580b57cec5SDimitry Andrictemplate <class C> constexpr auto crend(const C& c) -> decltype(std::rend(c));          // C++14
5590b57cec5SDimitry Andric
5600b57cec5SDimitry Andric// 24.8, container access:
5610b57cec5SDimitry Andrictemplate <class C> constexpr auto size(const C& c) -> decltype(c.size());         // C++17
5620b57cec5SDimitry Andrictemplate <class T, size_t N> constexpr size_t size(const T (&array)[N]) noexcept; // C++17
5630b57cec5SDimitry Andric
5640b57cec5SDimitry Andrictemplate <class C> constexpr auto ssize(const C& c)
5650b57cec5SDimitry Andric    -> common_type_t<ptrdiff_t, make_signed_t<decltype(c.size())>>;                    // C++20
5660b57cec5SDimitry Andrictemplate <class T, ptrdiff_t> constexpr ptrdiff_t ssize(const T (&array)[N]) noexcept; // C++20
5670b57cec5SDimitry Andric
5680b57cec5SDimitry Andrictemplate <class C> constexpr auto empty(const C& c) -> decltype(c.empty());       // C++17
5690b57cec5SDimitry Andrictemplate <class T, size_t N> constexpr bool empty(const T (&array)[N]) noexcept;  // C++17
5700b57cec5SDimitry Andrictemplate <class E> constexpr bool empty(initializer_list<E> il) noexcept;         // C++17
5710b57cec5SDimitry Andrictemplate <class C> constexpr auto data(C& c) -> decltype(c.data());               // C++17
5720b57cec5SDimitry Andrictemplate <class C> constexpr auto data(const C& c) -> decltype(c.data());         // C++17
5730b57cec5SDimitry Andrictemplate <class T, size_t N> constexpr T* data(T (&array)[N]) noexcept;           // C++17
5740b57cec5SDimitry Andrictemplate <class E> constexpr const E* data(initializer_list<E> il) noexcept;      // C++17
5750b57cec5SDimitry Andric
5760b57cec5SDimitry Andric}  // std
5770b57cec5SDimitry Andric
5780b57cec5SDimitry Andric*/
5790b57cec5SDimitry Andric
5800b57cec5SDimitry Andric#include <__config>
581fe6060f1SDimitry Andric#include <__debug>
5820b57cec5SDimitry Andric#include <__functional_base>
583fe6060f1SDimitry Andric#include <__iterator/access.h>
584fe6060f1SDimitry Andric#include <__iterator/advance.h>
585fe6060f1SDimitry Andric#include <__iterator/back_insert_iterator.h>
586fe6060f1SDimitry Andric#include <__iterator/common_iterator.h>
587fe6060f1SDimitry Andric#include <__iterator/concepts.h>
588fe6060f1SDimitry Andric#include <__iterator/counted_iterator.h>
589fe6060f1SDimitry Andric#include <__iterator/data.h>
590fe6060f1SDimitry Andric#include <__iterator/default_sentinel.h>
591fe6060f1SDimitry Andric#include <__iterator/distance.h>
592fe6060f1SDimitry Andric#include <__iterator/empty.h>
593fe6060f1SDimitry Andric#include <__iterator/erase_if_container.h>
594fe6060f1SDimitry Andric#include <__iterator/front_insert_iterator.h>
595fe6060f1SDimitry Andric#include <__iterator/incrementable_traits.h>
596fe6060f1SDimitry Andric#include <__iterator/insert_iterator.h>
597fe6060f1SDimitry Andric#include <__iterator/istreambuf_iterator.h>
598fe6060f1SDimitry Andric#include <__iterator/istream_iterator.h>
599fe6060f1SDimitry Andric#include <__iterator/iterator.h>
600fe6060f1SDimitry Andric#include <__iterator/iterator_traits.h>
601fe6060f1SDimitry Andric#include <__iterator/iter_move.h>
602fe6060f1SDimitry Andric#include <__iterator/iter_swap.h>
603fe6060f1SDimitry Andric#include <__iterator/move_iterator.h>
604fe6060f1SDimitry Andric#include <__iterator/next.h>
605fe6060f1SDimitry Andric#include <__iterator/ostreambuf_iterator.h>
606fe6060f1SDimitry Andric#include <__iterator/ostream_iterator.h>
607fe6060f1SDimitry Andric#include <__iterator/prev.h>
608fe6060f1SDimitry Andric#include <__iterator/projected.h>
609fe6060f1SDimitry Andric#include <__iterator/readable_traits.h>
610fe6060f1SDimitry Andric#include <__iterator/reverse_access.h>
611fe6060f1SDimitry Andric#include <__iterator/reverse_iterator.h>
612fe6060f1SDimitry Andric#include <__iterator/size.h>
613*349cc55cSDimitry Andric#include <__iterator/unreachable_sentinel.h>
614fe6060f1SDimitry Andric#include <__iterator/wrap_iter.h>
615fe6060f1SDimitry Andric#include <__memory/addressof.h>
616fe6060f1SDimitry Andric#include <__memory/pointer_traits.h>
617fe6060f1SDimitry Andric#include <__utility/forward.h>
618fe6060f1SDimitry Andric#include <compare>
619fe6060f1SDimitry Andric#include <concepts> // Mandated by the Standard.
6200b57cec5SDimitry Andric#include <cstddef>
6210b57cec5SDimitry Andric#include <initializer_list>
622fe6060f1SDimitry Andric#include <type_traits>
6230b57cec5SDimitry Andric#include <version>
6240b57cec5SDimitry Andric
6250b57cec5SDimitry Andric#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
6260b57cec5SDimitry Andric#pragma GCC system_header
6270b57cec5SDimitry Andric#endif
6280b57cec5SDimitry Andric
6290b57cec5SDimitry Andric#endif // _LIBCPP_ITERATOR
630