1 // Iterators -*- C++ -*-
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51 /** @file bits/stl_iterator.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{iterator}
55 * This file implements reverse_iterator, back_insert_iterator,
56 * front_insert_iterator, insert_iterator, __normal_iterator, and their
57 * supporting functions and overloaded operators.
60 #ifndef _STL_ITERATOR_H
61 #define _STL_ITERATOR_H 1
63 #include <bits/cpp_type_traits.h>
64 #include <ext/type_traits.h>
65 #include <bits/move.h>
66 #include <bits/ptr_traits.h>
68 namespace std _GLIBCXX_VISIBILITY(default)
70 _GLIBCXX_BEGIN_NAMESPACE_VERSION
73 * @addtogroup iterators
77 // 24.4.1 Reverse iterators
79 * Bidirectional and random access iterators have corresponding reverse
80 * %iterator adaptors that iterate through the data structure in the
81 * opposite direction. They have the same signatures as the corresponding
82 * iterators. The fundamental relation between a reverse %iterator and its
83 * corresponding %iterator @c i is established by the identity:
85 * &*(reverse_iterator(i)) == &*(i - 1)
88 * <em>This mapping is dictated by the fact that while there is always a
89 * pointer past the end of an array, there might not be a valid pointer
90 * before the beginning of an array.</em> [24.4.1]/1,2
92 * Reverse iterators can be tricky and surprising at first. Their
93 * semantics make sense, however, and the trickiness is a side effect of
94 * the requirement that the iterators must be safe.
96 template<typename _Iterator>
97 class reverse_iterator
98 : public iterator<typename iterator_traits<_Iterator>::iterator_category,
99 typename iterator_traits<_Iterator>::value_type,
100 typename iterator_traits<_Iterator>::difference_type,
101 typename iterator_traits<_Iterator>::pointer,
102 typename iterator_traits<_Iterator>::reference>
107 typedef iterator_traits<_Iterator> __traits_type;
110 typedef _Iterator iterator_type;
111 typedef typename __traits_type::difference_type difference_type;
112 typedef typename __traits_type::pointer pointer;
113 typedef typename __traits_type::reference reference;
116 * The default constructor value-initializes member @p current.
117 * If it is a pointer, that means it is zero-initialized.
119 // _GLIBCXX_RESOLVE_LIB_DEFECTS
120 // 235 No specification of default ctor for reverse_iterator
121 reverse_iterator() : current() { }
124 * This %iterator will move in the opposite direction that @p x does.
127 reverse_iterator(iterator_type __x) : current(__x) { }
130 * The copy constructor is normal.
132 reverse_iterator(const reverse_iterator& __x)
133 : current(__x.current) { }
136 * A %reverse_iterator across other types can be copied if the
137 * underlying %iterator can be converted to the type of @c current.
139 template<typename _Iter>
140 reverse_iterator(const reverse_iterator<_Iter>& __x)
141 : current(__x.base()) { }
144 * @return @c current, the %iterator used for underlying work.
151 * @return A reference to the value at @c --current
153 * This requires that @c --current is dereferenceable.
155 * @warning This implementation requires that for an iterator of the
156 * underlying iterator type, @c x, a reference obtained by
157 * @c *x remains valid after @c x has been modified or
158 * destroyed. This is a bug: http://gcc.gnu.org/PR51823
163 _Iterator __tmp = current;
168 * @return A pointer to the value at @c --current
170 * This requires that @c --current is dereferenceable.
174 { return &(operator*()); }
179 * Decrements the underlying iterator.
189 * @return The original value of @c *this
191 * Decrements the underlying iterator.
196 reverse_iterator __tmp = *this;
204 * Increments the underlying iterator.
214 * @return A reverse_iterator with the previous value of @c *this
216 * Increments the underlying iterator.
221 reverse_iterator __tmp = *this;
227 * @return A reverse_iterator that refers to @c current - @a __n
229 * The underlying iterator must be a Random Access Iterator.
232 operator+(difference_type __n) const
233 { return reverse_iterator(current - __n); }
238 * Moves the underlying iterator backwards @a __n steps.
239 * The underlying iterator must be a Random Access Iterator.
242 operator+=(difference_type __n)
249 * @return A reverse_iterator that refers to @c current - @a __n
251 * The underlying iterator must be a Random Access Iterator.
254 operator-(difference_type __n) const
255 { return reverse_iterator(current + __n); }
260 * Moves the underlying iterator forwards @a __n steps.
261 * The underlying iterator must be a Random Access Iterator.
264 operator-=(difference_type __n)
271 * @return The value at @c current - @a __n - 1
273 * The underlying iterator must be a Random Access Iterator.
276 operator[](difference_type __n) const
277 { return *(*this + __n); }
282 * @param __x A %reverse_iterator.
283 * @param __y A %reverse_iterator.
284 * @return A simple bool.
286 * Reverse iterators forward many operations to their underlying base()
287 * iterators. Others are implemented in terms of one another.
290 template<typename _Iterator>
292 operator==(const reverse_iterator<_Iterator>& __x,
293 const reverse_iterator<_Iterator>& __y)
294 { return __x.base() == __y.base(); }
296 template<typename _Iterator>
298 operator<(const reverse_iterator<_Iterator>& __x,
299 const reverse_iterator<_Iterator>& __y)
300 { return __y.base() < __x.base(); }
302 template<typename _Iterator>
304 operator!=(const reverse_iterator<_Iterator>& __x,
305 const reverse_iterator<_Iterator>& __y)
306 { return !(__x == __y); }
308 template<typename _Iterator>
310 operator>(const reverse_iterator<_Iterator>& __x,
311 const reverse_iterator<_Iterator>& __y)
312 { return __y < __x; }
314 template<typename _Iterator>
316 operator<=(const reverse_iterator<_Iterator>& __x,
317 const reverse_iterator<_Iterator>& __y)
318 { return !(__y < __x); }
320 template<typename _Iterator>
322 operator>=(const reverse_iterator<_Iterator>& __x,
323 const reverse_iterator<_Iterator>& __y)
324 { return !(__x < __y); }
326 template<typename _Iterator>
327 inline typename reverse_iterator<_Iterator>::difference_type
328 operator-(const reverse_iterator<_Iterator>& __x,
329 const reverse_iterator<_Iterator>& __y)
330 { return __y.base() - __x.base(); }
332 template<typename _Iterator>
333 inline reverse_iterator<_Iterator>
334 operator+(typename reverse_iterator<_Iterator>::difference_type __n,
335 const reverse_iterator<_Iterator>& __x)
336 { return reverse_iterator<_Iterator>(__x.base() - __n); }
338 // _GLIBCXX_RESOLVE_LIB_DEFECTS
339 // DR 280. Comparison of reverse_iterator to const reverse_iterator.
340 template<typename _IteratorL, typename _IteratorR>
342 operator==(const reverse_iterator<_IteratorL>& __x,
343 const reverse_iterator<_IteratorR>& __y)
344 { return __x.base() == __y.base(); }
346 template<typename _IteratorL, typename _IteratorR>
348 operator<(const reverse_iterator<_IteratorL>& __x,
349 const reverse_iterator<_IteratorR>& __y)
350 { return __y.base() < __x.base(); }
352 template<typename _IteratorL, typename _IteratorR>
354 operator!=(const reverse_iterator<_IteratorL>& __x,
355 const reverse_iterator<_IteratorR>& __y)
356 { return !(__x == __y); }
358 template<typename _IteratorL, typename _IteratorR>
360 operator>(const reverse_iterator<_IteratorL>& __x,
361 const reverse_iterator<_IteratorR>& __y)
362 { return __y < __x; }
364 template<typename _IteratorL, typename _IteratorR>
366 operator<=(const reverse_iterator<_IteratorL>& __x,
367 const reverse_iterator<_IteratorR>& __y)
368 { return !(__y < __x); }
370 template<typename _IteratorL, typename _IteratorR>
372 operator>=(const reverse_iterator<_IteratorL>& __x,
373 const reverse_iterator<_IteratorR>& __y)
374 { return !(__x < __y); }
376 template<typename _IteratorL, typename _IteratorR>
377 #if __cplusplus >= 201103L
380 operator-(const reverse_iterator<_IteratorL>& __x,
381 const reverse_iterator<_IteratorR>& __y)
382 -> decltype(__y.base() - __x.base())
384 inline typename reverse_iterator<_IteratorL>::difference_type
385 operator-(const reverse_iterator<_IteratorL>& __x,
386 const reverse_iterator<_IteratorR>& __y)
388 { return __y.base() - __x.base(); }
391 #if __cplusplus > 201103L
392 #define __cpp_lib_make_reverse_iterator 201402
394 // _GLIBCXX_RESOLVE_LIB_DEFECTS
395 // DR 2285. make_reverse_iterator
396 /// Generator function for reverse_iterator.
397 template<typename _Iterator>
398 inline reverse_iterator<_Iterator>
399 make_reverse_iterator(_Iterator __i)
400 { return reverse_iterator<_Iterator>(__i); }
403 // 24.4.2.2.1 back_insert_iterator
405 * @brief Turns assignment into insertion.
407 * These are output iterators, constructed from a container-of-T.
408 * Assigning a T to the iterator appends it to the container using
411 * Tip: Using the back_inserter function to create these iterators can
414 template<typename _Container>
415 class back_insert_iterator
416 : public iterator<output_iterator_tag, void, void, void, void>
419 _Container* container;
422 /// A nested typedef for the type of whatever container you used.
423 typedef _Container container_type;
425 /// The only way to create this %iterator is with a container.
427 back_insert_iterator(_Container& __x) : container(&__x) { }
430 * @param __value An instance of whatever type
431 * container_type::const_reference is; presumably a
432 * reference-to-const T for container<T>.
433 * @return This %iterator, for chained operations.
435 * This kind of %iterator doesn't really have a @a position in the
436 * container (you can think of the position as being permanently at
437 * the end, if you like). Assigning a value to the %iterator will
438 * always append the value to the end of the container.
440 #if __cplusplus < 201103L
441 back_insert_iterator&
442 operator=(typename _Container::const_reference __value)
444 container->push_back(__value);
448 back_insert_iterator&
449 operator=(const typename _Container::value_type& __value)
451 container->push_back(__value);
455 back_insert_iterator&
456 operator=(typename _Container::value_type&& __value)
458 container->push_back(std::move(__value));
463 /// Simply returns *this.
464 back_insert_iterator&
468 /// Simply returns *this. (This %iterator does not @a move.)
469 back_insert_iterator&
473 /// Simply returns *this. (This %iterator does not @a move.)
480 * @param __x A container of arbitrary type.
481 * @return An instance of back_insert_iterator working on @p __x.
483 * This wrapper function helps in creating back_insert_iterator instances.
484 * Typing the name of the %iterator requires knowing the precise full
485 * type of the container, which can be tedious and impedes generic
486 * programming. Using this function lets you take advantage of automatic
487 * template parameter deduction, making the compiler match the correct
490 template<typename _Container>
491 inline back_insert_iterator<_Container>
492 back_inserter(_Container& __x)
493 { return back_insert_iterator<_Container>(__x); }
496 * @brief Turns assignment into insertion.
498 * These are output iterators, constructed from a container-of-T.
499 * Assigning a T to the iterator prepends it to the container using
502 * Tip: Using the front_inserter function to create these iterators can
505 template<typename _Container>
506 class front_insert_iterator
507 : public iterator<output_iterator_tag, void, void, void, void>
510 _Container* container;
513 /// A nested typedef for the type of whatever container you used.
514 typedef _Container container_type;
516 /// The only way to create this %iterator is with a container.
517 explicit front_insert_iterator(_Container& __x) : container(&__x) { }
520 * @param __value An instance of whatever type
521 * container_type::const_reference is; presumably a
522 * reference-to-const T for container<T>.
523 * @return This %iterator, for chained operations.
525 * This kind of %iterator doesn't really have a @a position in the
526 * container (you can think of the position as being permanently at
527 * the front, if you like). Assigning a value to the %iterator will
528 * always prepend the value to the front of the container.
530 #if __cplusplus < 201103L
531 front_insert_iterator&
532 operator=(typename _Container::const_reference __value)
534 container->push_front(__value);
538 front_insert_iterator&
539 operator=(const typename _Container::value_type& __value)
541 container->push_front(__value);
545 front_insert_iterator&
546 operator=(typename _Container::value_type&& __value)
548 container->push_front(std::move(__value));
553 /// Simply returns *this.
554 front_insert_iterator&
558 /// Simply returns *this. (This %iterator does not @a move.)
559 front_insert_iterator&
563 /// Simply returns *this. (This %iterator does not @a move.)
564 front_insert_iterator
570 * @param __x A container of arbitrary type.
571 * @return An instance of front_insert_iterator working on @p x.
573 * This wrapper function helps in creating front_insert_iterator instances.
574 * Typing the name of the %iterator requires knowing the precise full
575 * type of the container, which can be tedious and impedes generic
576 * programming. Using this function lets you take advantage of automatic
577 * template parameter deduction, making the compiler match the correct
580 template<typename _Container>
581 inline front_insert_iterator<_Container>
582 front_inserter(_Container& __x)
583 { return front_insert_iterator<_Container>(__x); }
586 * @brief Turns assignment into insertion.
588 * These are output iterators, constructed from a container-of-T.
589 * Assigning a T to the iterator inserts it in the container at the
590 * %iterator's position, rather than overwriting the value at that
593 * (Sequences will actually insert a @e copy of the value before the
594 * %iterator's position.)
596 * Tip: Using the inserter function to create these iterators can
599 template<typename _Container>
600 class insert_iterator
601 : public iterator<output_iterator_tag, void, void, void, void>
604 _Container* container;
605 typename _Container::iterator iter;
608 /// A nested typedef for the type of whatever container you used.
609 typedef _Container container_type;
612 * The only way to create this %iterator is with a container and an
613 * initial position (a normal %iterator into the container).
615 insert_iterator(_Container& __x, typename _Container::iterator __i)
616 : container(&__x), iter(__i) {}
619 * @param __value An instance of whatever type
620 * container_type::const_reference is; presumably a
621 * reference-to-const T for container<T>.
622 * @return This %iterator, for chained operations.
624 * This kind of %iterator maintains its own position in the
625 * container. Assigning a value to the %iterator will insert the
626 * value into the container at the place before the %iterator.
628 * The position is maintained such that subsequent assignments will
629 * insert values immediately after one another. For example,
631 * // vector v contains A and Z
633 * insert_iterator i (v, ++v.begin());
638 * // vector v contains A, 1, 2, 3, and Z
641 #if __cplusplus < 201103L
643 operator=(typename _Container::const_reference __value)
645 iter = container->insert(iter, __value);
651 operator=(const typename _Container::value_type& __value)
653 iter = container->insert(iter, __value);
659 operator=(typename _Container::value_type&& __value)
661 iter = container->insert(iter, std::move(__value));
667 /// Simply returns *this.
672 /// Simply returns *this. (This %iterator does not @a move.)
677 /// Simply returns *this. (This %iterator does not @a move.)
684 * @param __x A container of arbitrary type.
685 * @return An instance of insert_iterator working on @p __x.
687 * This wrapper function helps in creating insert_iterator instances.
688 * Typing the name of the %iterator requires knowing the precise full
689 * type of the container, which can be tedious and impedes generic
690 * programming. Using this function lets you take advantage of automatic
691 * template parameter deduction, making the compiler match the correct
694 template<typename _Container, typename _Iterator>
695 inline insert_iterator<_Container>
696 inserter(_Container& __x, _Iterator __i)
698 return insert_iterator<_Container>(__x,
699 typename _Container::iterator(__i));
702 // @} group iterators
704 _GLIBCXX_END_NAMESPACE_VERSION
707 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
709 _GLIBCXX_BEGIN_NAMESPACE_VERSION
711 // This iterator adapter is @a normal in the sense that it does not
712 // change the semantics of any of the operators of its iterator
713 // parameter. Its primary purpose is to convert an iterator that is
714 // not a class, e.g. a pointer, into an iterator that is a class.
715 // The _Container parameter exists solely so that different containers
716 // using this template can instantiate different types, even if the
717 // _Iterator parameter is the same.
718 using std::iterator_traits;
720 template<typename _Iterator, typename _Container>
721 class __normal_iterator
724 _Iterator _M_current;
726 typedef iterator_traits<_Iterator> __traits_type;
729 typedef _Iterator iterator_type;
730 typedef typename __traits_type::iterator_category iterator_category;
731 typedef typename __traits_type::value_type value_type;
732 typedef typename __traits_type::difference_type difference_type;
733 typedef typename __traits_type::reference reference;
734 typedef typename __traits_type::pointer pointer;
736 _GLIBCXX_CONSTEXPR __normal_iterator() _GLIBCXX_NOEXCEPT
737 : _M_current(_Iterator()) { }
740 __normal_iterator(const _Iterator& __i) _GLIBCXX_NOEXCEPT
741 : _M_current(__i) { }
743 // Allow iterator to const_iterator conversion
744 template<typename _Iter>
745 __normal_iterator(const __normal_iterator<_Iter,
746 typename __enable_if<
747 (std::__are_same<_Iter, typename _Container::pointer>::__value),
748 _Container>::__type>& __i) _GLIBCXX_NOEXCEPT
749 : _M_current(__i.base()) { }
751 // Forward iterator requirements
753 operator*() const _GLIBCXX_NOEXCEPT
754 { return *_M_current; }
757 operator->() const _GLIBCXX_NOEXCEPT
758 { return _M_current; }
761 operator++() _GLIBCXX_NOEXCEPT
768 operator++(int) _GLIBCXX_NOEXCEPT
769 { return __normal_iterator(_M_current++); }
771 // Bidirectional iterator requirements
773 operator--() _GLIBCXX_NOEXCEPT
780 operator--(int) _GLIBCXX_NOEXCEPT
781 { return __normal_iterator(_M_current--); }
783 // Random access iterator requirements
785 operator[](difference_type __n) const _GLIBCXX_NOEXCEPT
786 { return _M_current[__n]; }
789 operator+=(difference_type __n) _GLIBCXX_NOEXCEPT
790 { _M_current += __n; return *this; }
793 operator+(difference_type __n) const _GLIBCXX_NOEXCEPT
794 { return __normal_iterator(_M_current + __n); }
797 operator-=(difference_type __n) _GLIBCXX_NOEXCEPT
798 { _M_current -= __n; return *this; }
801 operator-(difference_type __n) const _GLIBCXX_NOEXCEPT
802 { return __normal_iterator(_M_current - __n); }
805 base() const _GLIBCXX_NOEXCEPT
806 { return _M_current; }
809 // Note: In what follows, the left- and right-hand-side iterators are
810 // allowed to vary in types (conceptually in cv-qualification) so that
811 // comparison between cv-qualified and non-cv-qualified iterators be
812 // valid. However, the greedy and unfriendly operators in std::rel_ops
813 // will make overload resolution ambiguous (when in scope) if we don't
814 // provide overloads whose operands are of the same type. Can someone
815 // remind me what generic programming is about? -- Gaby
817 // Forward iterator requirements
818 template<typename _IteratorL, typename _IteratorR, typename _Container>
820 operator==(const __normal_iterator<_IteratorL, _Container>& __lhs,
821 const __normal_iterator<_IteratorR, _Container>& __rhs)
823 { return __lhs.base() == __rhs.base(); }
825 template<typename _Iterator, typename _Container>
827 operator==(const __normal_iterator<_Iterator, _Container>& __lhs,
828 const __normal_iterator<_Iterator, _Container>& __rhs)
830 { return __lhs.base() == __rhs.base(); }
832 template<typename _IteratorL, typename _IteratorR, typename _Container>
834 operator!=(const __normal_iterator<_IteratorL, _Container>& __lhs,
835 const __normal_iterator<_IteratorR, _Container>& __rhs)
837 { return __lhs.base() != __rhs.base(); }
839 template<typename _Iterator, typename _Container>
841 operator!=(const __normal_iterator<_Iterator, _Container>& __lhs,
842 const __normal_iterator<_Iterator, _Container>& __rhs)
844 { return __lhs.base() != __rhs.base(); }
846 // Random access iterator requirements
847 template<typename _IteratorL, typename _IteratorR, typename _Container>
849 operator<(const __normal_iterator<_IteratorL, _Container>& __lhs,
850 const __normal_iterator<_IteratorR, _Container>& __rhs)
852 { return __lhs.base() < __rhs.base(); }
854 template<typename _Iterator, typename _Container>
856 operator<(const __normal_iterator<_Iterator, _Container>& __lhs,
857 const __normal_iterator<_Iterator, _Container>& __rhs)
859 { return __lhs.base() < __rhs.base(); }
861 template<typename _IteratorL, typename _IteratorR, typename _Container>
863 operator>(const __normal_iterator<_IteratorL, _Container>& __lhs,
864 const __normal_iterator<_IteratorR, _Container>& __rhs)
866 { return __lhs.base() > __rhs.base(); }
868 template<typename _Iterator, typename _Container>
870 operator>(const __normal_iterator<_Iterator, _Container>& __lhs,
871 const __normal_iterator<_Iterator, _Container>& __rhs)
873 { return __lhs.base() > __rhs.base(); }
875 template<typename _IteratorL, typename _IteratorR, typename _Container>
877 operator<=(const __normal_iterator<_IteratorL, _Container>& __lhs,
878 const __normal_iterator<_IteratorR, _Container>& __rhs)
880 { return __lhs.base() <= __rhs.base(); }
882 template<typename _Iterator, typename _Container>
884 operator<=(const __normal_iterator<_Iterator, _Container>& __lhs,
885 const __normal_iterator<_Iterator, _Container>& __rhs)
887 { return __lhs.base() <= __rhs.base(); }
889 template<typename _IteratorL, typename _IteratorR, typename _Container>
891 operator>=(const __normal_iterator<_IteratorL, _Container>& __lhs,
892 const __normal_iterator<_IteratorR, _Container>& __rhs)
894 { return __lhs.base() >= __rhs.base(); }
896 template<typename _Iterator, typename _Container>
898 operator>=(const __normal_iterator<_Iterator, _Container>& __lhs,
899 const __normal_iterator<_Iterator, _Container>& __rhs)
901 { return __lhs.base() >= __rhs.base(); }
903 // _GLIBCXX_RESOLVE_LIB_DEFECTS
904 // According to the resolution of DR179 not only the various comparison
905 // operators but also operator- must accept mixed iterator/const_iterator
907 template<typename _IteratorL, typename _IteratorR, typename _Container>
908 #if __cplusplus >= 201103L
911 operator-(const __normal_iterator<_IteratorL, _Container>& __lhs,
912 const __normal_iterator<_IteratorR, _Container>& __rhs) noexcept
913 -> decltype(__lhs.base() - __rhs.base())
915 inline typename __normal_iterator<_IteratorL, _Container>::difference_type
916 operator-(const __normal_iterator<_IteratorL, _Container>& __lhs,
917 const __normal_iterator<_IteratorR, _Container>& __rhs)
919 { return __lhs.base() - __rhs.base(); }
921 template<typename _Iterator, typename _Container>
922 inline typename __normal_iterator<_Iterator, _Container>::difference_type
923 operator-(const __normal_iterator<_Iterator, _Container>& __lhs,
924 const __normal_iterator<_Iterator, _Container>& __rhs)
926 { return __lhs.base() - __rhs.base(); }
928 template<typename _Iterator, typename _Container>
929 inline __normal_iterator<_Iterator, _Container>
930 operator+(typename __normal_iterator<_Iterator, _Container>::difference_type
931 __n, const __normal_iterator<_Iterator, _Container>& __i)
933 { return __normal_iterator<_Iterator, _Container>(__i.base() + __n); }
935 _GLIBCXX_END_NAMESPACE_VERSION
938 #if __cplusplus >= 201103L
940 namespace std _GLIBCXX_VISIBILITY(default)
942 _GLIBCXX_BEGIN_NAMESPACE_VERSION
945 * @addtogroup iterators
949 // 24.4.3 Move iterators
951 * Class template move_iterator is an iterator adapter with the same
952 * behavior as the underlying iterator except that its dereference
953 * operator implicitly converts the value returned by the underlying
954 * iterator's dereference operator to an rvalue reference. Some
955 * generic algorithms can be called with move iterators to replace
956 * copying with moving.
958 template<typename _Iterator>
962 _Iterator _M_current;
964 typedef iterator_traits<_Iterator> __traits_type;
965 typedef typename __traits_type::reference __base_ref;
968 typedef _Iterator iterator_type;
969 typedef typename __traits_type::iterator_category iterator_category;
970 typedef typename __traits_type::value_type value_type;
971 typedef typename __traits_type::difference_type difference_type;
973 typedef _Iterator pointer;
974 // _GLIBCXX_RESOLVE_LIB_DEFECTS
975 // 2106. move_iterator wrapping iterators returning prvalues
976 typedef typename conditional<is_reference<__base_ref>::value,
977 typename remove_reference<__base_ref>::type&&,
978 __base_ref>::type reference;
984 move_iterator(iterator_type __i)
985 : _M_current(__i) { }
987 template<typename _Iter>
988 move_iterator(const move_iterator<_Iter>& __i)
989 : _M_current(__i.base()) { }
993 { return _M_current; }
997 { return static_cast<reference>(*_M_current); }
1001 { return _M_current; }
1013 move_iterator __tmp = *this;
1028 move_iterator __tmp = *this;
1034 operator+(difference_type __n) const
1035 { return move_iterator(_M_current + __n); }
1038 operator+=(difference_type __n)
1045 operator-(difference_type __n) const
1046 { return move_iterator(_M_current - __n); }
1049 operator-=(difference_type __n)
1056 operator[](difference_type __n) const
1057 { return std::move(_M_current[__n]); }
1060 // Note: See __normal_iterator operators note from Gaby to understand
1061 // why there are always 2 versions for most of the move_iterator
1063 template<typename _IteratorL, typename _IteratorR>
1065 operator==(const move_iterator<_IteratorL>& __x,
1066 const move_iterator<_IteratorR>& __y)
1067 { return __x.base() == __y.base(); }
1069 template<typename _Iterator>
1071 operator==(const move_iterator<_Iterator>& __x,
1072 const move_iterator<_Iterator>& __y)
1073 { return __x.base() == __y.base(); }
1075 template<typename _IteratorL, typename _IteratorR>
1077 operator!=(const move_iterator<_IteratorL>& __x,
1078 const move_iterator<_IteratorR>& __y)
1079 { return !(__x == __y); }
1081 template<typename _Iterator>
1083 operator!=(const move_iterator<_Iterator>& __x,
1084 const move_iterator<_Iterator>& __y)
1085 { return !(__x == __y); }
1087 template<typename _IteratorL, typename _IteratorR>
1089 operator<(const move_iterator<_IteratorL>& __x,
1090 const move_iterator<_IteratorR>& __y)
1091 { return __x.base() < __y.base(); }
1093 template<typename _Iterator>
1095 operator<(const move_iterator<_Iterator>& __x,
1096 const move_iterator<_Iterator>& __y)
1097 { return __x.base() < __y.base(); }
1099 template<typename _IteratorL, typename _IteratorR>
1101 operator<=(const move_iterator<_IteratorL>& __x,
1102 const move_iterator<_IteratorR>& __y)
1103 { return !(__y < __x); }
1105 template<typename _Iterator>
1107 operator<=(const move_iterator<_Iterator>& __x,
1108 const move_iterator<_Iterator>& __y)
1109 { return !(__y < __x); }
1111 template<typename _IteratorL, typename _IteratorR>
1113 operator>(const move_iterator<_IteratorL>& __x,
1114 const move_iterator<_IteratorR>& __y)
1115 { return __y < __x; }
1117 template<typename _Iterator>
1119 operator>(const move_iterator<_Iterator>& __x,
1120 const move_iterator<_Iterator>& __y)
1121 { return __y < __x; }
1123 template<typename _IteratorL, typename _IteratorR>
1125 operator>=(const move_iterator<_IteratorL>& __x,
1126 const move_iterator<_IteratorR>& __y)
1127 { return !(__x < __y); }
1129 template<typename _Iterator>
1131 operator>=(const move_iterator<_Iterator>& __x,
1132 const move_iterator<_Iterator>& __y)
1133 { return !(__x < __y); }
1136 template<typename _IteratorL, typename _IteratorR>
1138 operator-(const move_iterator<_IteratorL>& __x,
1139 const move_iterator<_IteratorR>& __y)
1140 -> decltype(__x.base() - __y.base())
1141 { return __x.base() - __y.base(); }
1143 template<typename _Iterator>
1145 operator-(const move_iterator<_Iterator>& __x,
1146 const move_iterator<_Iterator>& __y)
1147 -> decltype(__x.base() - __y.base())
1148 { return __x.base() - __y.base(); }
1150 template<typename _Iterator>
1151 inline move_iterator<_Iterator>
1152 operator+(typename move_iterator<_Iterator>::difference_type __n,
1153 const move_iterator<_Iterator>& __x)
1154 { return __x + __n; }
1156 template<typename _Iterator>
1157 inline move_iterator<_Iterator>
1158 make_move_iterator(_Iterator __i)
1159 { return move_iterator<_Iterator>(__i); }
1161 template<typename _Iterator, typename _ReturnType
1162 = typename conditional<__move_if_noexcept_cond
1163 <typename iterator_traits<_Iterator>::value_type>::value,
1164 _Iterator, move_iterator<_Iterator>>::type>
1166 __make_move_if_noexcept_iterator(_Iterator __i)
1167 { return _ReturnType(__i); }
1169 // @} group iterators
1171 _GLIBCXX_END_NAMESPACE_VERSION
1174 #define _GLIBCXX_MAKE_MOVE_ITERATOR(_Iter) std::make_move_iterator(_Iter)
1175 #define _GLIBCXX_MAKE_MOVE_IF_NOEXCEPT_ITERATOR(_Iter) \
1176 std::__make_move_if_noexcept_iterator(_Iter)
1178 #define _GLIBCXX_MAKE_MOVE_ITERATOR(_Iter) (_Iter)
1179 #define _GLIBCXX_MAKE_MOVE_IF_NOEXCEPT_ITERATOR(_Iter) (_Iter)