1// -*- C++ -*-
2//===-------------------------- iterator ----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_ITERATOR
12#define _LIBCPP_ITERATOR
13
14/*
15    iterator synopsis
16
17namespace std
18{
19
20template<class Iterator>
21struct iterator_traits
22{
23    typedef typename Iterator::difference_type difference_type;
24    typedef typename Iterator::value_type value_type;
25    typedef typename Iterator::pointer pointer;
26    typedef typename Iterator::reference reference;
27    typedef typename Iterator::iterator_category iterator_category;
28};
29
30template<class T>
31struct iterator_traits<T*>
32{
33    typedef ptrdiff_t difference_type;
34    typedef T value_type;
35    typedef T* pointer;
36    typedef T& reference;
37    typedef random_access_iterator_tag iterator_category;
38};
39
40template<class T>
41struct iterator_traits<const T*>
42{
43    typedef ptrdiff_t difference_type;
44    typedef T value_type;
45    typedef const T* pointer;
46    typedef const T& reference;
47    typedef random_access_iterator_tag iterator_category;
48};
49
50template<class Category, class T, class Distance = ptrdiff_t,
51         class Pointer = T*, class Reference = T&>
52struct iterator
53{
54    typedef T         value_type;
55    typedef Distance  difference_type;
56    typedef Pointer   pointer;
57    typedef Reference reference;
58    typedef Category  iterator_category;
59};
60
61struct input_iterator_tag  {};
62struct output_iterator_tag {};
63struct forward_iterator_tag       : public input_iterator_tag         {};
64struct bidirectional_iterator_tag : public forward_iterator_tag       {};
65struct random_access_iterator_tag : public bidirectional_iterator_tag {};
66
67// extension: second argument not conforming to C++03
68template <class InputIterator>
69void advance(InputIterator& i,
70             typename iterator_traits<InputIterator>::difference_type n);
71
72template <class InputIterator>
73typename iterator_traits<InputIterator>::difference_type
74distance(InputIterator first, InputIterator last);
75
76template <class Iterator>
77class reverse_iterator
78    : public iterator<typename iterator_traits<Iterator>::iterator_category,
79                      typename iterator_traits<Iterator>::value_type,
80                      typename iterator_traits<Iterator>::difference_type,
81                      typename iterator_traits<Iterator>::pointer,
82                      typename iterator_traits<Iterator>::reference>
83{
84protected:
85    Iterator current;
86public:
87    typedef Iterator                                            iterator_type;
88    typedef typename iterator_traits<Iterator>::difference_type difference_type;
89    typedef typename iterator_traits<Iterator>::reference       reference;
90    typedef typename iterator_traits<Iterator>::pointer         pointer;
91
92    reverse_iterator();
93    explicit reverse_iterator(Iterator x);
94    template <class U> reverse_iterator(const reverse_iterator<U>& u);
95    Iterator base() const;
96    reference operator*() const;
97    pointer   operator->() const;
98    reverse_iterator& operator++();
99    reverse_iterator  operator++(int);
100    reverse_iterator& operator--();
101    reverse_iterator  operator--(int);
102    reverse_iterator  operator+ (difference_type n) const;
103    reverse_iterator& operator+=(difference_type n);
104    reverse_iterator  operator- (difference_type n) const;
105    reverse_iterator& operator-=(difference_type n);
106    reference         operator[](difference_type n) const;
107};
108
109template <class Iterator1, class Iterator2>
110bool
111operator==(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
112
113template <class Iterator1, class Iterator2>
114bool
115operator<(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
116
117template <class Iterator1, class Iterator2>
118bool
119operator!=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
120
121template <class Iterator1, class Iterator2>
122bool
123operator>(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
124
125template <class Iterator1, class Iterator2>
126bool
127operator>=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
128
129template <class Iterator1, class Iterator2>
130bool
131operator<=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
132
133template <class Iterator1, class Iterator2>
134typename reverse_iterator<Iterator1>::difference_type
135operator-(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
136
137template <class Iterator>
138reverse_iterator<Iterator>
139operator+(typename reverse_iterator<Iterator>::difference_type n, const reverse_iterator<Iterator>& x);
140
141template <class Container>
142class back_insert_iterator
143{
144protected:
145    Container* container;
146public:
147    typedef Container                   container_type;
148    typedef void                        value_type;
149    typedef void                        difference_type;
150    typedef back_insert_iterator<Cont>& reference;
151    typedef void                        pointer;
152
153    explicit back_insert_iterator(Container& x);
154    back_insert_iterator& operator=(const typename Container::value_type& value);
155    back_insert_iterator& operator*();
156    back_insert_iterator& operator++();
157    back_insert_iterator  operator++(int);
158};
159
160template <class Container> back_insert_iterator<Container> back_inserter(Container& x);
161
162template <class Container>
163class front_insert_iterator
164{
165protected:
166    Container* container;
167public:
168    typedef Container                    container_type;
169    typedef void                         value_type;
170    typedef void                         difference_type;
171    typedef front_insert_iterator<Cont>& reference;
172    typedef void                         pointer;
173
174    explicit front_insert_iterator(Container& x);
175    front_insert_iterator& operator=(const typename Container::value_type& value);
176    front_insert_iterator& operator*();
177    front_insert_iterator& operator++();
178    front_insert_iterator  operator++(int);
179};
180
181template <class Container> front_insert_iterator<Container> front_inserter(Container& x);
182
183template <class Container>
184class insert_iterator
185{
186protected:
187    Container* container;
188    typename Container::iterator iter;
189public:
190    typedef Container              container_type;
191    typedef void                   value_type;
192    typedef void                   difference_type;
193    typedef insert_iterator<Cont>& reference;
194    typedef void                   pointer;
195
196    insert_iterator(Container& x, typename Container::iterator i);
197    insert_iterator& operator=(const typename Container::value_type& value);
198    insert_iterator& operator*();
199    insert_iterator& operator++();
200    insert_iterator& operator++(int);
201};
202
203template <class Container, class Iterator>
204insert_iterator<Container> inserter(Container& x, Iterator i);
205
206template <class T, class charT = char, class traits = char_traits<charT>, class Distance = ptrdiff_t>
207class istream_iterator
208    : public iterator<input_iterator_tag, T, Distance, const T*, const T&>
209{
210public:
211    typedef charT char_type;
212    typedef traits traits_type;
213    typedef basic_istream<charT,traits> istream_type;
214
215    istream_iterator();
216    istream_iterator(istream_type& s);
217    istream_iterator(const istream_iterator& x);
218    ~istream_iterator();
219
220    const T& operator*() const;
221    const T* operator->() const;
222    istream_iterator& operator++();
223    istream_iterator  operator++(int);
224};
225
226template <class T, class charT, class traits, class Distance>
227bool operator==(const istream_iterator<T,charT,traits,Distance>& x,
228                const istream_iterator<T,charT,traits,Distance>& y);
229template <class T, class charT, class traits, class Distance>
230bool operator!=(const istream_iterator<T,charT,traits,Distance>& x,
231                const istream_iterator<T,charT,traits,Distance>& y);
232
233template <class T, class charT = char, class traits = char_traits<charT> >
234class ostream_iterator
235    : public iterator<output_iterator_tag, void, void, void ,void>
236{
237public:
238    typedef charT char_type;
239    typedef traits traits_type;
240    typedef basic_ostream<charT,traits> ostream_type;
241
242    ostream_iterator(ostream_type& s);
243    ostream_iterator(ostream_type& s, const charT* delimiter);
244    ostream_iterator(const ostream_iterator& x);
245    ~ostream_iterator();
246    ostream_iterator& operator=(const T& value);
247
248    ostream_iterator& operator*();
249    ostream_iterator& operator++();
250    ostream_iterator& operator++(int);
251};
252
253template<class charT, class traits = char_traits<charT> >
254class istreambuf_iterator
255    : public iterator<input_iterator_tag, charT,
256                      typename traits::off_type, unspecified,
257                      charT>
258{
259public:
260    typedef charT                         char_type;
261    typedef traits                        traits_type;
262    typedef typename traits::int_type     int_type;
263    typedef basic_streambuf<charT,traits> streambuf_type;
264    typedef basic_istream<charT,traits>   istream_type;
265
266    istreambuf_iterator() throw();
267    istreambuf_iterator(istream_type& s) throw();
268    istreambuf_iterator(streambuf_type* s) throw();
269    istreambuf_iterator(a-private-type) throw();
270
271    charT                operator*() const;
272    pointer operator->() const;
273    istreambuf_iterator& operator++();
274    a-private-type       operator++(int);
275
276    bool equal(const istreambuf_iterator& b) const;
277};
278
279template <class charT, class traits>
280bool operator==(const istreambuf_iterator<charT,traits>& a,
281                const istreambuf_iterator<charT,traits>& b);
282template <class charT, class traits>
283bool operator!=(const istreambuf_iterator<charT,traits>& a,
284                const istreambuf_iterator<charT,traits>& b);
285
286template <class charT, class traits = char_traits<charT> >
287class ostreambuf_iterator
288    : public iterator<output_iterator_tag, void, void, void, void>
289{
290public:
291    typedef charT                         char_type;
292    typedef traits                        traits_type;
293    typedef basic_streambuf<charT,traits> streambuf_type;
294    typedef basic_ostream<charT,traits>   ostream_type;
295
296    ostreambuf_iterator(ostream_type& s) throw();
297    ostreambuf_iterator(streambuf_type* s) throw();
298    ostreambuf_iterator& operator=(charT c);
299    ostreambuf_iterator& operator*();
300    ostreambuf_iterator& operator++();
301    ostreambuf_iterator& operator++(int);
302    bool failed() const throw();
303};
304
305template <class C> auto begin(C& c) -> decltype(c.begin());
306template <class C> auto begin(const C& c) -> decltype(c.begin());
307template <class C> auto end(C& c) -> decltype(c.end());
308template <class C> auto end(const C& c) -> decltype(c.end());
309template <class T, size_t N> T* begin(T (&array)[N]);
310template <class T, size_t N> T* end(T (&array)[N]);
311
312}  // std
313
314*/
315
316#include <__config>
317#include <type_traits>
318#include <cstddef>
319#include <iosfwd>
320#ifdef _LIBCPP_DEBUG
321#include <cassert>
322#endif
323
324#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
325#pragma GCC system_header
326#endif
327
328_LIBCPP_BEGIN_NAMESPACE_STD
329
330struct _LIBCPP_VISIBLE input_iterator_tag {};
331struct _LIBCPP_VISIBLE output_iterator_tag {};
332struct _LIBCPP_VISIBLE forward_iterator_tag       : public input_iterator_tag {};
333struct _LIBCPP_VISIBLE bidirectional_iterator_tag : public forward_iterator_tag {};
334struct _LIBCPP_VISIBLE random_access_iterator_tag : public bidirectional_iterator_tag {};
335
336template <class _Tp>
337struct __has_iterator_category
338{
339private:
340    struct __two {char _; char __;};
341    template <class _Up> static __two __test(...);
342    template <class _Up> static char __test(typename _Up::iterator_category* = 0);
343public:
344    static const bool value = sizeof(__test<_Tp>(0)) == 1;
345};
346
347template <class _Iter, bool> struct ____iterator_traits {};
348
349template <class _Iter>
350struct ____iterator_traits<_Iter, true>
351{
352    typedef typename _Iter::difference_type   difference_type;
353    typedef typename _Iter::value_type        value_type;
354    typedef typename _Iter::pointer           pointer;
355    typedef typename _Iter::reference         reference;
356    typedef typename _Iter::iterator_category iterator_category;
357};
358
359template <class _Iter, bool> struct __iterator_traits {};
360
361template <class _Iter>
362struct __iterator_traits<_Iter, true>
363    :  ____iterator_traits
364      <
365        _Iter,
366        is_convertible<typename _Iter::iterator_category, input_iterator_tag>::value ||
367        is_convertible<typename _Iter::iterator_category, output_iterator_tag>::value
368      >
369{};
370
371// iterator_traits<Iterator> will only have the nested types if Iterator::iterator_category
372//    exists.  Else iterator_traits<Iterator> will be an empty class.  This is a
373//    conforming extension which allows some programs to compile and behave as
374//    the client expects instead of failing at compile time.
375
376template <class _Iter>
377struct _LIBCPP_VISIBLE iterator_traits
378    : __iterator_traits<_Iter, __has_iterator_category<_Iter>::value> {};
379
380template<class _Tp>
381struct _LIBCPP_VISIBLE iterator_traits<_Tp*>
382{
383    typedef ptrdiff_t difference_type;
384    typedef typename remove_const<_Tp>::type value_type;
385    typedef _Tp* pointer;
386    typedef _Tp& reference;
387    typedef random_access_iterator_tag iterator_category;
388};
389
390template <class _Tp, class _Up, bool = __has_iterator_category<iterator_traits<_Tp> >::value>
391struct __has_iterator_category_convertible_to
392    : public integral_constant<bool, is_convertible<typename iterator_traits<_Tp>::iterator_category, _Up>::value>
393{};
394
395template <class _Tp, class _Up>
396struct __has_iterator_category_convertible_to<_Tp, _Up, false> : public false_type {};
397
398template <class _Tp>
399struct __is_input_iterator : public __has_iterator_category_convertible_to<_Tp, input_iterator_tag> {};
400
401template <class _Tp>
402struct __is_forward_iterator : public __has_iterator_category_convertible_to<_Tp, forward_iterator_tag> {};
403
404template <class _Tp>
405struct __is_bidirectional_iterator : public __has_iterator_category_convertible_to<_Tp, bidirectional_iterator_tag> {};
406
407template <class _Tp>
408struct __is_random_access_iterator : public __has_iterator_category_convertible_to<_Tp, random_access_iterator_tag> {};
409
410template<class _Category, class _Tp, class _Distance = ptrdiff_t,
411         class _Pointer = _Tp*, class _Reference = _Tp&>
412struct _LIBCPP_VISIBLE iterator
413{
414    typedef _Tp        value_type;
415    typedef _Distance  difference_type;
416    typedef _Pointer   pointer;
417    typedef _Reference reference;
418    typedef _Category  iterator_category;
419};
420
421template <class _InputIter>
422inline _LIBCPP_INLINE_VISIBILITY
423void __advance(_InputIter& __i,
424             typename iterator_traits<_InputIter>::difference_type __n, input_iterator_tag)
425{
426    for (; __n > 0; --__n)
427        ++__i;
428}
429
430template <class _BiDirIter>
431inline _LIBCPP_INLINE_VISIBILITY
432void __advance(_BiDirIter& __i,
433             typename iterator_traits<_BiDirIter>::difference_type __n, bidirectional_iterator_tag)
434{
435    if (__n >= 0)
436        for (; __n > 0; --__n)
437            ++__i;
438    else
439        for (; __n < 0; ++__n)
440            --__i;
441}
442
443template <class _RandIter>
444inline _LIBCPP_INLINE_VISIBILITY
445void __advance(_RandIter& __i,
446             typename iterator_traits<_RandIter>::difference_type __n, random_access_iterator_tag)
447{
448   __i += __n;
449}
450
451template <class _InputIter>
452inline _LIBCPP_INLINE_VISIBILITY
453void advance(_InputIter& __i,
454             typename iterator_traits<_InputIter>::difference_type __n)
455{
456    __advance(__i, __n, typename iterator_traits<_InputIter>::iterator_category());
457}
458
459template <class _InputIter>
460inline _LIBCPP_INLINE_VISIBILITY
461typename iterator_traits<_InputIter>::difference_type
462__distance(_InputIter __first, _InputIter __last, input_iterator_tag)
463{
464    typename iterator_traits<_InputIter>::difference_type __r(0);
465    for (; __first != __last; ++__first)
466        ++__r;
467    return __r;
468}
469
470template <class _RandIter>
471inline _LIBCPP_INLINE_VISIBILITY
472typename iterator_traits<_RandIter>::difference_type
473__distance(_RandIter __first, _RandIter __last, random_access_iterator_tag)
474{
475    return __last - __first;
476}
477
478template <class _InputIter>
479inline _LIBCPP_INLINE_VISIBILITY
480typename iterator_traits<_InputIter>::difference_type
481distance(_InputIter __first, _InputIter __last)
482{
483    return __distance(__first, __last, typename iterator_traits<_InputIter>::iterator_category());
484}
485
486template <class _ForwardIter>
487inline _LIBCPP_INLINE_VISIBILITY
488_ForwardIter
489next(_ForwardIter __x,
490     typename iterator_traits<_ForwardIter>::difference_type __n = 1,
491     typename enable_if<__is_forward_iterator<_ForwardIter>::value>::type* = 0)
492{
493    _VSTD::advance(__x, __n);
494    return __x;
495}
496
497template <class _BidiretionalIter>
498inline _LIBCPP_INLINE_VISIBILITY
499_BidiretionalIter
500prev(_BidiretionalIter __x,
501     typename iterator_traits<_BidiretionalIter>::difference_type __n = 1,
502     typename enable_if<__is_bidirectional_iterator<_BidiretionalIter>::value>::type* = 0)
503{
504    _VSTD::advance(__x, -__n);
505    return __x;
506}
507
508template <class _Iter>
509class _LIBCPP_VISIBLE reverse_iterator
510    : public iterator<typename iterator_traits<_Iter>::iterator_category,
511                      typename iterator_traits<_Iter>::value_type,
512                      typename iterator_traits<_Iter>::difference_type,
513                      typename iterator_traits<_Iter>::pointer,
514                      typename iterator_traits<_Iter>::reference>
515{
516private:
517    mutable _Iter __t;
518protected:
519    _Iter current;
520public:
521    typedef _Iter                                            iterator_type;
522    typedef typename iterator_traits<_Iter>::difference_type difference_type;
523    typedef typename iterator_traits<_Iter>::reference       reference;
524    typedef typename iterator_traits<_Iter>::pointer         pointer;
525
526    _LIBCPP_INLINE_VISIBILITY reverse_iterator() : current() {}
527    _LIBCPP_INLINE_VISIBILITY explicit reverse_iterator(_Iter __x) : __t(__x), current(__x) {}
528    template <class _Up> _LIBCPP_INLINE_VISIBILITY reverse_iterator(const reverse_iterator<_Up>& __u)
529        : __t(__u.base()), current(__u.base()) {}
530    _LIBCPP_INLINE_VISIBILITY _Iter base() const {return current;}
531    _LIBCPP_INLINE_VISIBILITY reference operator*() const {__t = current; return *--__t;}
532    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const {return &(operator*());}
533    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator++() {--current; return *this;}
534    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator++(int)
535        {reverse_iterator __tmp(*this); --current; return __tmp;}
536    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator--() {++current; return *this;}
537    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator--(int)
538        {reverse_iterator __tmp(*this); ++current; return __tmp;}
539    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator+ (difference_type __n) const
540        {return reverse_iterator(current - __n);}
541    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator+=(difference_type __n)
542        {current -= __n; return *this;}
543    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator- (difference_type __n) const
544        {return reverse_iterator(current + __n);}
545    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator-=(difference_type __n)
546        {current += __n; return *this;}
547    _LIBCPP_INLINE_VISIBILITY reference         operator[](difference_type __n) const
548        {return current[-__n-1];}
549};
550
551template <class _Iter1, class _Iter2>
552inline _LIBCPP_INLINE_VISIBILITY
553bool
554operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
555{
556    return __x.base() == __y.base();
557}
558
559template <class _Iter1, class _Iter2>
560inline _LIBCPP_INLINE_VISIBILITY
561bool
562operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
563{
564    return __x.base() > __y.base();
565}
566
567template <class _Iter1, class _Iter2>
568inline _LIBCPP_INLINE_VISIBILITY
569bool
570operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
571{
572    return __x.base() != __y.base();
573}
574
575template <class _Iter1, class _Iter2>
576inline _LIBCPP_INLINE_VISIBILITY
577bool
578operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
579{
580    return __x.base() < __y.base();
581}
582
583template <class _Iter1, class _Iter2>
584inline _LIBCPP_INLINE_VISIBILITY
585bool
586operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
587{
588    return __x.base() <= __y.base();
589}
590
591template <class _Iter1, class _Iter2>
592inline _LIBCPP_INLINE_VISIBILITY
593bool
594operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
595{
596    return __x.base() >= __y.base();
597}
598
599template <class _Iter1, class _Iter2>
600inline _LIBCPP_INLINE_VISIBILITY
601typename reverse_iterator<_Iter1>::difference_type
602operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
603{
604    return __y.base() - __x.base();
605}
606
607template <class _Iter>
608inline _LIBCPP_INLINE_VISIBILITY
609reverse_iterator<_Iter>
610operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_iterator<_Iter>& __x)
611{
612    return reverse_iterator<_Iter>(__x.base() - __n);
613}
614
615template <class _Container>
616class _LIBCPP_VISIBLE back_insert_iterator
617    : public iterator<output_iterator_tag,
618                      void,
619                      void,
620                      void,
621                      back_insert_iterator<_Container>&>
622{
623protected:
624    _Container* container;
625public:
626    typedef _Container container_type;
627
628    _LIBCPP_INLINE_VISIBILITY explicit back_insert_iterator(_Container& __x) : container(&__x) {}
629    _LIBCPP_INLINE_VISIBILITY back_insert_iterator& operator=(const typename _Container::value_type& __value_)
630        {container->push_back(__value_); return *this;}
631#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
632    _LIBCPP_INLINE_VISIBILITY back_insert_iterator& operator=(typename _Container::value_type&& __value_)
633        {container->push_back(_VSTD::move(__value_)); return *this;}
634#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
635    _LIBCPP_INLINE_VISIBILITY back_insert_iterator& operator*()     {return *this;}
636    _LIBCPP_INLINE_VISIBILITY back_insert_iterator& operator++()    {return *this;}
637    _LIBCPP_INLINE_VISIBILITY back_insert_iterator  operator++(int) {return *this;}
638};
639
640template <class _Container>
641inline _LIBCPP_INLINE_VISIBILITY
642back_insert_iterator<_Container>
643back_inserter(_Container& __x)
644{
645    return back_insert_iterator<_Container>(__x);
646}
647
648template <class _Container>
649class _LIBCPP_VISIBLE front_insert_iterator
650    : public iterator<output_iterator_tag,
651                      void,
652                      void,
653                      void,
654                      front_insert_iterator<_Container>&>
655{
656protected:
657    _Container* container;
658public:
659    typedef _Container container_type;
660
661    _LIBCPP_INLINE_VISIBILITY explicit front_insert_iterator(_Container& __x) : container(&__x) {}
662    _LIBCPP_INLINE_VISIBILITY front_insert_iterator& operator=(const typename _Container::value_type& __value_)
663        {container->push_front(__value_); return *this;}
664#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
665    _LIBCPP_INLINE_VISIBILITY front_insert_iterator& operator=(typename _Container::value_type&& __value_)
666        {container->push_front(_VSTD::move(__value_)); return *this;}
667#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
668    _LIBCPP_INLINE_VISIBILITY front_insert_iterator& operator*()     {return *this;}
669    _LIBCPP_INLINE_VISIBILITY front_insert_iterator& operator++()    {return *this;}
670    _LIBCPP_INLINE_VISIBILITY front_insert_iterator  operator++(int) {return *this;}
671};
672
673template <class _Container>
674inline _LIBCPP_INLINE_VISIBILITY
675front_insert_iterator<_Container>
676front_inserter(_Container& __x)
677{
678    return front_insert_iterator<_Container>(__x);
679}
680
681template <class _Container>
682class _LIBCPP_VISIBLE insert_iterator
683    : public iterator<output_iterator_tag,
684                      void,
685                      void,
686                      void,
687                      insert_iterator<_Container>&>
688{
689protected:
690    _Container* container;
691    typename _Container::iterator iter;
692public:
693    typedef _Container container_type;
694
695    _LIBCPP_INLINE_VISIBILITY insert_iterator(_Container& __x, typename _Container::iterator __i)
696        : container(&__x), iter(__i) {}
697    _LIBCPP_INLINE_VISIBILITY insert_iterator& operator=(const typename _Container::value_type& __value_)
698        {iter = container->insert(iter, __value_); ++iter; return *this;}
699#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
700    _LIBCPP_INLINE_VISIBILITY insert_iterator& operator=(typename _Container::value_type&& __value_)
701        {iter = container->insert(iter, _VSTD::move(__value_)); ++iter; return *this;}
702#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
703    _LIBCPP_INLINE_VISIBILITY insert_iterator& operator*()        {return *this;}
704    _LIBCPP_INLINE_VISIBILITY insert_iterator& operator++()       {return *this;}
705    _LIBCPP_INLINE_VISIBILITY insert_iterator& operator++(int)    {return *this;}
706};
707
708template <class _Container>
709inline _LIBCPP_INLINE_VISIBILITY
710insert_iterator<_Container>
711inserter(_Container& __x, typename _Container::iterator __i)
712{
713    return insert_iterator<_Container>(__x, __i);
714}
715
716template <class _Tp, class _CharT = char,
717          class _Traits = char_traits<_CharT>, class _Distance = ptrdiff_t>
718class _LIBCPP_VISIBLE istream_iterator
719    : public iterator<input_iterator_tag, _Tp, _Distance, const _Tp*, const _Tp&>
720{
721public:
722    typedef _CharT char_type;
723    typedef _Traits traits_type;
724    typedef basic_istream<_CharT,_Traits> istream_type;
725private:
726    istream_type* __in_stream_;
727    _Tp __value_;
728public:
729    _LIBCPP_INLINE_VISIBILITY istream_iterator() : __in_stream_(0) {}
730    _LIBCPP_INLINE_VISIBILITY istream_iterator(istream_type& __s) : __in_stream_(&__s)
731        {
732            if (!(*__in_stream_ >> __value_))
733                __in_stream_ = 0;
734        }
735
736    _LIBCPP_INLINE_VISIBILITY const _Tp& operator*() const {return __value_;}
737    _LIBCPP_INLINE_VISIBILITY const _Tp* operator->() const {return &(operator*());}
738    _LIBCPP_INLINE_VISIBILITY istream_iterator& operator++()
739        {
740            if (!(*__in_stream_ >> __value_))
741                __in_stream_ = 0;
742            return *this;
743        }
744    _LIBCPP_INLINE_VISIBILITY istream_iterator  operator++(int)
745        {istream_iterator __t(*this); ++(*this); return __t;}
746
747    friend _LIBCPP_INLINE_VISIBILITY
748    bool operator==(const istream_iterator& __x, const istream_iterator& __y)
749        {return __x.__in_stream_ == __y.__in_stream_;}
750
751    friend _LIBCPP_INLINE_VISIBILITY
752    bool operator!=(const istream_iterator& __x, const istream_iterator& __y)
753        {return !(__x == __y);}
754};
755
756template <class _Tp, class _CharT = char, class _Traits = char_traits<_CharT> >
757class _LIBCPP_VISIBLE ostream_iterator
758    : public iterator<output_iterator_tag, void, void, void, void>
759{
760public:
761    typedef _CharT char_type;
762    typedef _Traits traits_type;
763    typedef basic_ostream<_CharT,_Traits> ostream_type;
764private:
765    ostream_type* __out_stream_;
766    const char_type* __delim_;
767public:
768    _LIBCPP_INLINE_VISIBILITY ostream_iterator(ostream_type& __s)
769        : __out_stream_(&__s), __delim_(0) {}
770    _LIBCPP_INLINE_VISIBILITY ostream_iterator(ostream_type& __s, const _CharT* __delimiter)
771        : __out_stream_(&__s), __delim_(__delimiter) {}
772    _LIBCPP_INLINE_VISIBILITY ostream_iterator& operator=(const _Tp& __value_)
773        {
774            *__out_stream_ << __value_;
775            if (__delim_)
776                *__out_stream_ << __delim_;
777            return *this;
778        }
779
780    _LIBCPP_INLINE_VISIBILITY ostream_iterator& operator*()     {return *this;}
781    _LIBCPP_INLINE_VISIBILITY ostream_iterator& operator++()    {return *this;}
782    _LIBCPP_INLINE_VISIBILITY ostream_iterator& operator++(int) {return *this;}
783};
784
785template<class _CharT, class _Traits>
786class _LIBCPP_VISIBLE istreambuf_iterator
787    : public iterator<input_iterator_tag, _CharT,
788                      typename _Traits::off_type, _CharT*,
789                      _CharT>
790{
791public:
792    typedef _CharT                          char_type;
793    typedef _Traits                         traits_type;
794    typedef typename _Traits::int_type      int_type;
795    typedef basic_streambuf<_CharT,_Traits> streambuf_type;
796    typedef basic_istream<_CharT,_Traits>   istream_type;
797private:
798    streambuf_type* __sbuf_;
799
800    class __proxy
801    {
802        char_type __keep_;
803        streambuf_type* __sbuf_;
804        _LIBCPP_INLINE_VISIBILITY __proxy(char_type __c, streambuf_type* __s)
805            : __keep_(__c), __sbuf_(__s) {}
806        friend class istreambuf_iterator;
807    public:
808        _LIBCPP_INLINE_VISIBILITY char_type operator*() const {return __keep_;}
809    };
810
811    _LIBCPP_INLINE_VISIBILITY
812    void __test_for_eof()
813    {
814        if (__sbuf_ && traits_type::eq_int_type(__sbuf_->sgetc(), traits_type::eof()))
815            __sbuf_ = 0;
816    }
817public:
818    _LIBCPP_INLINE_VISIBILITY istreambuf_iterator() throw() : __sbuf_(0) {}
819    _LIBCPP_INLINE_VISIBILITY istreambuf_iterator(istream_type& __s) throw()
820        : __sbuf_(__s.rdbuf()) {__test_for_eof();}
821    _LIBCPP_INLINE_VISIBILITY istreambuf_iterator(streambuf_type* __s) throw()
822        : __sbuf_(__s) {__test_for_eof();}
823    _LIBCPP_INLINE_VISIBILITY istreambuf_iterator(const __proxy& __p) throw()
824        : __sbuf_(__p.__sbuf_) {}
825
826    _LIBCPP_INLINE_VISIBILITY _CharT     operator*() const {return __sbuf_->sgetc();}
827    _LIBCPP_INLINE_VISIBILITY char_type* operator->() const {return nullptr;}
828    _LIBCPP_INLINE_VISIBILITY istreambuf_iterator& operator++()
829        {
830            if (traits_type::eq_int_type(__sbuf_->snextc(), traits_type::eof()))
831                __sbuf_ = 0;
832            return *this;
833        }
834    _LIBCPP_INLINE_VISIBILITY __proxy              operator++(int)
835        {
836            char_type __c = __sbuf_->sgetc();
837            ++(*this);
838            return __proxy(__c, __sbuf_);
839        }
840
841    _LIBCPP_INLINE_VISIBILITY bool equal(const istreambuf_iterator& __b) const
842        {return (__sbuf_ == 0) == (__b.__sbuf_ == 0);}
843};
844
845template <class _CharT, class _Traits>
846inline _LIBCPP_INLINE_VISIBILITY
847bool operator==(const istreambuf_iterator<_CharT,_Traits>& __a,
848                const istreambuf_iterator<_CharT,_Traits>& __b)
849                {return __a.equal(__b);}
850
851template <class _CharT, class _Traits>
852inline _LIBCPP_INLINE_VISIBILITY
853bool operator!=(const istreambuf_iterator<_CharT,_Traits>& __a,
854                const istreambuf_iterator<_CharT,_Traits>& __b)
855                {return !__a.equal(__b);}
856
857template <class _CharT, class _Traits>
858class _LIBCPP_VISIBLE ostreambuf_iterator
859    : public iterator<output_iterator_tag, void, void, void, void>
860{
861public:
862    typedef _CharT                          char_type;
863    typedef _Traits                         traits_type;
864    typedef basic_streambuf<_CharT,_Traits> streambuf_type;
865    typedef basic_ostream<_CharT,_Traits>   ostream_type;
866private:
867    streambuf_type* __sbuf_;
868public:
869    _LIBCPP_INLINE_VISIBILITY ostreambuf_iterator(ostream_type& __s) throw()
870        : __sbuf_(__s.rdbuf()) {}
871    _LIBCPP_INLINE_VISIBILITY ostreambuf_iterator(streambuf_type* __s) throw()
872        : __sbuf_(__s) {}
873    _LIBCPP_INLINE_VISIBILITY ostreambuf_iterator& operator=(_CharT __c)
874        {
875            if (__sbuf_ && traits_type::eq_int_type(__sbuf_->sputc(__c), traits_type::eof()))
876                __sbuf_ = 0;
877            return *this;
878        }
879    _LIBCPP_INLINE_VISIBILITY ostreambuf_iterator& operator*()     {return *this;}
880    _LIBCPP_INLINE_VISIBILITY ostreambuf_iterator& operator++()    {return *this;}
881    _LIBCPP_INLINE_VISIBILITY ostreambuf_iterator& operator++(int) {return *this;}
882    _LIBCPP_INLINE_VISIBILITY bool failed() const throw() {return __sbuf_ == 0;}
883};
884
885template <class _Iter>
886class _LIBCPP_VISIBLE move_iterator
887{
888private:
889    _Iter __i;
890public:
891    typedef _Iter                                            iterator_type;
892    typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
893    typedef typename iterator_traits<iterator_type>::value_type value_type;
894    typedef typename iterator_traits<iterator_type>::difference_type difference_type;
895    typedef typename iterator_traits<iterator_type>::pointer pointer;
896#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
897    typedef value_type&& reference;
898#else
899    typedef typename iterator_traits<iterator_type>::reference reference;
900#endif
901
902    _LIBCPP_INLINE_VISIBILITY move_iterator() : __i() {}
903    _LIBCPP_INLINE_VISIBILITY explicit move_iterator(_Iter __x) : __i(__x) {}
904    template <class _Up> _LIBCPP_INLINE_VISIBILITY move_iterator(const move_iterator<_Up>& __u)
905        : __i(__u.base()) {}
906    _LIBCPP_INLINE_VISIBILITY _Iter base() const {return __i;}
907    _LIBCPP_INLINE_VISIBILITY reference operator*() const {
908      return static_cast<reference>(*__i);
909    }
910    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const {
911      typename iterator_traits<iterator_type>::reference __ref = *__i;
912      return &__ref;
913    }
914    _LIBCPP_INLINE_VISIBILITY move_iterator& operator++() {++__i; return *this;}
915    _LIBCPP_INLINE_VISIBILITY move_iterator  operator++(int)
916        {move_iterator __tmp(*this); ++__i; return __tmp;}
917    _LIBCPP_INLINE_VISIBILITY move_iterator& operator--() {--__i; return *this;}
918    _LIBCPP_INLINE_VISIBILITY move_iterator  operator--(int)
919        {move_iterator __tmp(*this); --__i; return __tmp;}
920    _LIBCPP_INLINE_VISIBILITY move_iterator  operator+ (difference_type __n) const
921        {return move_iterator(__i + __n);}
922    _LIBCPP_INLINE_VISIBILITY move_iterator& operator+=(difference_type __n)
923        {__i += __n; return *this;}
924    _LIBCPP_INLINE_VISIBILITY move_iterator  operator- (difference_type __n) const
925        {return move_iterator(__i - __n);}
926    _LIBCPP_INLINE_VISIBILITY move_iterator& operator-=(difference_type __n)
927        {__i -= __n; return *this;}
928    _LIBCPP_INLINE_VISIBILITY reference         operator[](difference_type __n) const
929    {
930      return static_cast<reference>(__i[__n]);
931    }
932};
933
934template <class _Iter1, class _Iter2>
935inline _LIBCPP_INLINE_VISIBILITY
936bool
937operator==(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
938{
939    return __x.base() == __y.base();
940}
941
942template <class _Iter1, class _Iter2>
943inline _LIBCPP_INLINE_VISIBILITY
944bool
945operator<(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
946{
947    return __x.base() < __y.base();
948}
949
950template <class _Iter1, class _Iter2>
951inline _LIBCPP_INLINE_VISIBILITY
952bool
953operator!=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
954{
955    return __x.base() != __y.base();
956}
957
958template <class _Iter1, class _Iter2>
959inline _LIBCPP_INLINE_VISIBILITY
960bool
961operator>(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
962{
963    return __x.base() > __y.base();
964}
965
966template <class _Iter1, class _Iter2>
967inline _LIBCPP_INLINE_VISIBILITY
968bool
969operator>=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
970{
971    return __x.base() >= __y.base();
972}
973
974template <class _Iter1, class _Iter2>
975inline _LIBCPP_INLINE_VISIBILITY
976bool
977operator<=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
978{
979    return __x.base() <= __y.base();
980}
981
982template <class _Iter1, class _Iter2>
983inline _LIBCPP_INLINE_VISIBILITY
984typename move_iterator<_Iter1>::difference_type
985operator-(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
986{
987    return __x.base() - __y.base();
988}
989
990template <class _Iter>
991inline _LIBCPP_INLINE_VISIBILITY
992move_iterator<_Iter>
993operator+(typename move_iterator<_Iter>::difference_type __n, const move_iterator<_Iter>& __x)
994{
995    return move_iterator<_Iter>(__x.base() + __n);
996}
997
998template <class _Iter>
999inline _LIBCPP_INLINE_VISIBILITY
1000move_iterator<_Iter>
1001make_move_iterator(const _Iter& __i)
1002{
1003    return move_iterator<_Iter>(__i);
1004}
1005
1006// __wrap_iter
1007
1008template <class _Iter> class __wrap_iter;
1009
1010template <class _Iter1, class _Iter2>
1011bool
1012operator==(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1013
1014template <class _Iter1, class _Iter2>
1015bool
1016operator<(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1017
1018template <class _Iter1, class _Iter2>
1019bool
1020operator!=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1021
1022template <class _Iter1, class _Iter2>
1023bool
1024operator>(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1025
1026template <class _Iter1, class _Iter2>
1027bool
1028operator>=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1029
1030template <class _Iter1, class _Iter2>
1031bool
1032operator<=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1033
1034template <class _Iter1, class _Iter2>
1035typename __wrap_iter<_Iter1>::difference_type
1036operator-(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1037
1038template <class _Iter>
1039__wrap_iter<_Iter>
1040operator+(typename __wrap_iter<_Iter>::difference_type, __wrap_iter<_Iter>) _NOEXCEPT;
1041
1042template <class _I, class _O> _O copy(_I, _I, _O);
1043template <class _B1, class _B2> _B2 copy_backward(_B1, _B1, _B2);
1044template <class _I, class _O> _O move(_I, _I, _O);
1045template <class _B1, class _B2> _B2 move_backward(_B1, _B1, _B2);
1046
1047template <class _Tp>
1048typename enable_if
1049<
1050    is_trivially_copy_assignable<_Tp>::value,
1051    _Tp*
1052>::type
1053__unwrap_iter(__wrap_iter<_Tp*>);
1054
1055template <class _Iter>
1056class __wrap_iter
1057{
1058public:
1059    typedef _Iter                                                      iterator_type;
1060    typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
1061    typedef typename iterator_traits<iterator_type>::value_type        value_type;
1062    typedef typename iterator_traits<iterator_type>::difference_type   difference_type;
1063    typedef typename iterator_traits<iterator_type>::pointer           pointer;
1064    typedef typename iterator_traits<iterator_type>::reference         reference;
1065private:
1066    iterator_type __i;
1067public:
1068    _LIBCPP_INLINE_VISIBILITY __wrap_iter() _NOEXCEPT
1069    {
1070#if _LIBCPP_DEBUG_LEVEL >= 2
1071        __get_db()->__insert_i(this);
1072#endif
1073    }
1074    template <class _Up> _LIBCPP_INLINE_VISIBILITY __wrap_iter(const __wrap_iter<_Up>& __u,
1075        typename enable_if<is_convertible<_Up, iterator_type>::value>::type* = 0) _NOEXCEPT
1076        : __i(__u.base())
1077    {
1078#if _LIBCPP_DEBUG_LEVEL >= 2
1079        __get_db()->__iterator_copy(this, &__u);
1080#endif
1081    }
1082#if _LIBCPP_DEBUG_LEVEL >= 2
1083    _LIBCPP_INLINE_VISIBILITY
1084    __wrap_iter(const __wrap_iter& __x)
1085        : __i(__x.base())
1086    {
1087        __get_db()->__iterator_copy(this, &__x);
1088    }
1089    _LIBCPP_INLINE_VISIBILITY
1090    __wrap_iter& operator=(const __wrap_iter& __x)
1091    {
1092        if (this != &__x)
1093        {
1094            __get_db()->__iterator_copy(this, &__x);
1095            __i = __x.__i;
1096        }
1097        return *this;
1098    }
1099    _LIBCPP_INLINE_VISIBILITY
1100    ~__wrap_iter()
1101    {
1102        __get_db()->__erase_i(this);
1103    }
1104#endif
1105    _LIBCPP_INLINE_VISIBILITY reference operator*() const _NOEXCEPT
1106    {
1107#if _LIBCPP_DEBUG_LEVEL >= 2
1108        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
1109                       "Attempted to dereference a non-dereferenceable iterator");
1110#endif
1111        return *__i;
1112    }
1113    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const _NOEXCEPT {return &(operator*());}
1114    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator++() _NOEXCEPT
1115    {
1116#if _LIBCPP_DEBUG_LEVEL >= 2
1117        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
1118                       "Attempted to increment non-incrementable iterator");
1119#endif
1120        ++__i;
1121        return *this;
1122    }
1123    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator++(int) _NOEXCEPT
1124        {__wrap_iter __tmp(*this); ++(*this); return __tmp;}
1125    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator--() _NOEXCEPT
1126    {
1127#if _LIBCPP_DEBUG_LEVEL >= 2
1128        _LIBCPP_ASSERT(__get_const_db()->__decrementable(this),
1129                       "Attempted to decrement non-decrementable iterator");
1130#endif
1131        --__i;
1132        return *this;
1133    }
1134    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator--(int) _NOEXCEPT
1135        {__wrap_iter __tmp(*this); --(*this); return __tmp;}
1136    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator+ (difference_type __n) const _NOEXCEPT
1137        {__wrap_iter __w(*this); __w += __n; return __w;}
1138    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator+=(difference_type __n) _NOEXCEPT
1139    {
1140#if _LIBCPP_DEBUG_LEVEL >= 2
1141        _LIBCPP_ASSERT(__get_const_db()->__addable(this, __n),
1142                   "Attempted to add/subtract iterator outside of valid range");
1143#endif
1144        __i += __n;
1145        return *this;
1146    }
1147    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator- (difference_type __n) const _NOEXCEPT
1148        {return *this + (-__n);}
1149    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator-=(difference_type __n) _NOEXCEPT
1150        {*this += -__n; return *this;}
1151    _LIBCPP_INLINE_VISIBILITY reference        operator[](difference_type __n) const _NOEXCEPT
1152    {
1153#if _LIBCPP_DEBUG_LEVEL >= 2
1154        _LIBCPP_ASSERT(__get_const_db()->__subscriptable(this, __n),
1155                   "Attempted to subscript iterator outside of valid range");
1156#endif
1157        return __i[__n];
1158    }
1159
1160    _LIBCPP_INLINE_VISIBILITY iterator_type base() const _NOEXCEPT {return __i;}
1161
1162private:
1163    _LIBCPP_INLINE_VISIBILITY __wrap_iter(iterator_type __x) _NOEXCEPT : __i(__x) {}
1164#if _LIBCPP_DEBUG_LEVEL >= 2
1165    _LIBCPP_INLINE_VISIBILITY __wrap_iter(const void* __p, iterator_type __x) : __i(__x)
1166    {
1167        __get_db()->__insert_ic(this, __p);
1168    }
1169#endif
1170
1171    template <class _Up> friend class __wrap_iter;
1172    template <class _CharT, class _Traits, class _Alloc> friend class basic_string;
1173    template <class _Tp, class _Alloc> friend class vector;
1174
1175    template <class _Iter1, class _Iter2>
1176    friend
1177    bool
1178    operator==(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1179
1180    template <class _Iter1, class _Iter2>
1181    friend
1182    bool
1183    operator<(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1184
1185    template <class _Iter1, class _Iter2>
1186    friend
1187    bool
1188    operator!=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1189
1190    template <class _Iter1, class _Iter2>
1191    friend
1192    bool
1193    operator>(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1194
1195    template <class _Iter1, class _Iter2>
1196    friend
1197    bool
1198    operator>=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1199
1200    template <class _Iter1, class _Iter2>
1201    friend
1202    bool
1203    operator<=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1204
1205    template <class _Iter1, class _Iter2>
1206    friend
1207    typename __wrap_iter<_Iter1>::difference_type
1208    operator-(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
1209
1210    template <class _Iter1>
1211    friend
1212    __wrap_iter<_Iter1>
1213    operator+(typename __wrap_iter<_Iter1>::difference_type, __wrap_iter<_Iter1>) _NOEXCEPT;
1214
1215    template <class _I, class _O> friend _O copy(_I, _I, _O);
1216    template <class _B1, class _B2> friend _B2 copy_backward(_B1, _B1, _B2);
1217    template <class _I, class _O> friend _O move(_I, _I, _O);
1218    template <class _B1, class _B2> friend _B2 move_backward(_B1, _B1, _B2);
1219
1220    template <class _Tp>
1221    friend
1222    typename enable_if
1223    <
1224        is_trivially_copy_assignable<_Tp>::value,
1225        _Tp*
1226    >::type
1227    __unwrap_iter(__wrap_iter<_Tp*>);
1228};
1229
1230template <class _Iter1, class _Iter2>
1231inline _LIBCPP_INLINE_VISIBILITY
1232bool
1233operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
1234{
1235#if _LIBCPP_DEBUG_LEVEL >= 2
1236    _LIBCPP_ASSERT(__get_const_db()->__comparable(&__x, &__y),
1237                   "Attempted to compare incomparable iterators");
1238#endif
1239    return __x.base() == __y.base();
1240}
1241
1242template <class _Iter1, class _Iter2>
1243inline _LIBCPP_INLINE_VISIBILITY
1244bool
1245operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
1246{
1247#if _LIBCPP_DEBUG_LEVEL >= 2
1248    _LIBCPP_ASSERT(__get_const_db()->__comparable(&__x, &__y),
1249                   "Attempted to compare incomparable iterators");
1250#endif
1251    return __x.base() < __y.base();
1252}
1253
1254template <class _Iter1, class _Iter2>
1255inline _LIBCPP_INLINE_VISIBILITY
1256bool
1257operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
1258{
1259    return !(__x == __y);
1260}
1261
1262template <class _Iter1, class _Iter2>
1263inline _LIBCPP_INLINE_VISIBILITY
1264bool
1265operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
1266{
1267    return __y < __x;
1268}
1269
1270template <class _Iter1, class _Iter2>
1271inline _LIBCPP_INLINE_VISIBILITY
1272bool
1273operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
1274{
1275    return !(__x < __y);
1276}
1277
1278template <class _Iter1, class _Iter2>
1279inline _LIBCPP_INLINE_VISIBILITY
1280bool
1281operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
1282{
1283    return !(__y < __x);
1284}
1285
1286template <class _Iter1, class _Iter2>
1287inline _LIBCPP_INLINE_VISIBILITY
1288typename __wrap_iter<_Iter1>::difference_type
1289operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
1290{
1291#if _LIBCPP_DEBUG_LEVEL >= 2
1292    _LIBCPP_ASSERT(__get_const_db()->__comparable(&__x, &__y),
1293                   "Attempted to subtract incompatible iterators");
1294#endif
1295    return __x.base() - __y.base();
1296}
1297
1298template <class _Iter>
1299inline _LIBCPP_INLINE_VISIBILITY
1300__wrap_iter<_Iter>
1301operator+(typename __wrap_iter<_Iter>::difference_type __n,
1302          __wrap_iter<_Iter> __x) _NOEXCEPT
1303{
1304    __x += __n;
1305    return __x;
1306}
1307
1308#ifdef _LIBCPP_DEBUG
1309
1310// __debug_iter
1311
1312template <class _Container, class _Iter> class __debug_iter;
1313
1314template <class _Container, class _Iter1, class _Iter2>
1315bool
1316operator==(const __debug_iter<_Container, _Iter1>&, const __debug_iter<_Container, _Iter2>&);
1317
1318template <class _Container, class _Iter1, class _Iter2>
1319bool
1320operator<(const __debug_iter<_Container, _Iter1>&, const __debug_iter<_Container, _Iter2>&);
1321
1322template <class _Container, class _Iter1, class _Iter2>
1323bool
1324operator!=(const __debug_iter<_Container, _Iter1>&, const __debug_iter<_Container, _Iter2>&);
1325
1326template <class _Container, class _Iter1, class _Iter2>
1327bool
1328operator>(const __debug_iter<_Container, _Iter1>&, const __debug_iter<_Container, _Iter2>&);
1329
1330template <class _Container, class _Iter1, class _Iter2>
1331bool
1332operator>=(const __debug_iter<_Container, _Iter1>&, const __debug_iter<_Container, _Iter2>&);
1333
1334template <class _Container, class _Iter1, class _Iter2>
1335bool
1336operator<=(const __debug_iter<_Container, _Iter1>&, const __debug_iter<_Container, _Iter2>&);
1337
1338template <class _Container, class _Iter1, class _Iter2>
1339typename __debug_iter<_Container, _Iter1>::difference_type
1340operator-(const __debug_iter<_Container, _Iter1>&, const __debug_iter<_Container, _Iter2>&);
1341
1342template <class _Container, class _Iter>
1343__debug_iter<_Container, _Iter>
1344operator+(typename __debug_iter<_Container, _Iter>::difference_type, const __debug_iter<_Container, _Iter>&);
1345
1346template <class _Container, class _Iter>
1347class __debug_iter
1348{
1349public:
1350    typedef _Iter                                                      iterator_type;
1351    typedef _Container                                                 __container_type;
1352    typedef typename iterator_traits<iterator_type>::iterator_category iterator_category;
1353    typedef typename iterator_traits<iterator_type>::value_type        value_type;
1354    typedef typename iterator_traits<iterator_type>::difference_type   difference_type;
1355    typedef typename iterator_traits<iterator_type>::pointer           pointer;
1356    typedef typename iterator_traits<iterator_type>::reference         reference;
1357private:
1358    iterator_type __i;
1359    __debug_iter* __next;
1360    __container_type* __cont;
1361
1362public:
1363    _LIBCPP_INLINE_VISIBILITY __debug_iter() : __next(0), __cont(0) {}
1364    _LIBCPP_INLINE_VISIBILITY __debug_iter(const __debug_iter& __x)
1365        : __i(__x.base()), __next(0), __cont(0) {__set_owner(__x.__cont);}
1366    __debug_iter& operator=(const __debug_iter& __x);
1367    template <class _Up> _LIBCPP_INLINE_VISIBILITY __debug_iter(const __debug_iter<_Container, _Up>& __u,
1368        typename enable_if<is_convertible<_Up, iterator_type>::value>::type* = 0)
1369        : __i(__u.base()), __next(0), __cont(0) {__set_owner(__u.__cont);}
1370    _LIBCPP_INLINE_VISIBILITY ~__debug_iter() {__remove_owner();}
1371    _LIBCPP_INLINE_VISIBILITY reference operator*() const {assert(__is_deref()); return *__i;}
1372    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const {return &(operator*());}
1373    _LIBCPP_INLINE_VISIBILITY __debug_iter& operator++() {assert(__can_increment()); ++__i; return *this;}
1374    _LIBCPP_INLINE_VISIBILITY __debug_iter  operator++(int)
1375        {__debug_iter __tmp(*this); operator++(); return __tmp;}
1376    _LIBCPP_INLINE_VISIBILITY __debug_iter& operator--() {assert(__can_decrement()); --__i; return *this;}
1377    _LIBCPP_INLINE_VISIBILITY __debug_iter  operator--(int)
1378        {__debug_iter __tmp(*this); operator--(); return __tmp;}
1379    _LIBCPP_INLINE_VISIBILITY __debug_iter  operator+ (difference_type __n) const
1380        {__debug_iter __t(*this); __t += __n; return __t;}
1381    __debug_iter& operator+=(difference_type __n);
1382    _LIBCPP_INLINE_VISIBILITY __debug_iter  operator- (difference_type __n) const
1383        {__debug_iter __t(*this); __t -= __n; return __t;}
1384    _LIBCPP_INLINE_VISIBILITY __debug_iter& operator-=(difference_type __n)
1385        {*this += -__n; return *this;}
1386    _LIBCPP_INLINE_VISIBILITY reference        operator[](difference_type __n) const
1387        {return *(*this + __n);}
1388
1389private:
1390    _LIBCPP_INLINE_VISIBILITY __debug_iter(const __container_type* __c, iterator_type __x)
1391        : __i(__x), __next(0), __cont(0) {__set_owner(__c);}
1392    _LIBCPP_INLINE_VISIBILITY iterator_type base() const {return __i;}
1393
1394    void __set_owner(const __container_type* __c);
1395    void __remove_owner();
1396    static void __remove_all(__container_type* __c);
1397    static void swap(__container_type* __x, __container_type* __y);
1398
1399    _LIBCPP_INLINE_VISIBILITY bool __is_deref() const
1400        {return __is_deref(__is_random_access_iterator<iterator_type>());}
1401    bool __is_deref(false_type) const;
1402    bool __is_deref(true_type) const;
1403    _LIBCPP_INLINE_VISIBILITY bool __can_decrement() const
1404        {return __can_decrement(integral_constant<int, is_pointer<iterator_type>::value ? 2:
1405                                                       __is_random_access_iterator<iterator_type>::value ? 1 : 0>());}
1406    bool __can_decrement(integral_constant<int, 0>) const;
1407    bool __can_decrement(integral_constant<int, 1>) const;
1408    bool __can_decrement(integral_constant<int, 2>) const;
1409    _LIBCPP_INLINE_VISIBILITY bool __can_increment() const
1410        {return __can_increment(integral_constant<int, is_pointer<iterator_type>::value ? 2:
1411                                                       __is_random_access_iterator<iterator_type>::value ? 1 : 0>());}
1412    bool __can_increment(integral_constant<int, 0>) const;
1413    bool __can_increment(integral_constant<int, 1>) const;
1414    bool __can_increment(integral_constant<int, 2>) const;
1415
1416    _LIBCPP_INLINE_VISIBILITY bool __can_add(difference_type __n) const
1417        {return __can_add(__n, is_pointer<iterator_type>());}
1418    bool __can_add(difference_type __n, false_type) const;
1419    bool __can_add(difference_type __n, true_type) const;
1420
1421    template <class _Cp, class _Up> friend class __debug_iter;
1422    friend class _Container::__self;
1423
1424    template <class _Cp, class _Iter1, class _Iter2>
1425    friend
1426    bool
1427    operator==(const __debug_iter<_Cp, _Iter1>&, const __debug_iter<_Cp, _Iter2>&);
1428
1429    template <class _Cp, class _Iter1, class _Iter2>
1430    friend
1431    bool
1432    operator<(const __debug_iter<_Cp, _Iter1>&, const __debug_iter<_Cp, _Iter2>&);
1433
1434    template <class _Cp, class _Iter1, class _Iter2>
1435    friend
1436    bool
1437    operator!=(const __debug_iter<_Cp, _Iter1>&, const __debug_iter<_Cp, _Iter2>&);
1438
1439    template <class _Cp, class _Iter1, class _Iter2>
1440    friend
1441    bool
1442    operator>(const __debug_iter<_Cp, _Iter1>&, const __debug_iter<_Cp, _Iter2>&);
1443
1444    template <class _Cp, class _Iter1, class _Iter2>
1445    friend
1446    bool
1447    operator>=(const __debug_iter<_Cp, _Iter1>&, const __debug_iter<_Cp, _Iter2>&);
1448
1449    template <class _Cp, class _Iter1, class _Iter2>
1450    friend
1451    bool
1452    operator<=(const __debug_iter<_Cp, _Iter1>&, const __debug_iter<_Cp, _Iter2>&);
1453
1454    template <class _Cp, class _Iter1, class _Iter2>
1455    friend
1456    typename __debug_iter<_Cp, _Iter1>::difference_type
1457    operator-(const __debug_iter<_Cp, _Iter1>&, const __debug_iter<_Cp, _Iter2>&);
1458
1459    template <class _Cp, class _Iter1>
1460    friend
1461    __debug_iter<_Cp, _Iter1>
1462    operator+(typename __debug_iter<_Cp, _Iter1>::difference_type, const __debug_iter<_Cp, _Iter1>&);
1463};
1464
1465template <class _Container, class _Iter>
1466__debug_iter<_Container, _Iter>&
1467__debug_iter<_Container, _Iter>::operator=(const __debug_iter& __x)
1468{
1469    if (this != &__x)
1470    {
1471        __remove_owner();
1472        __i = __x.__i;
1473        __set_owner(__x.__cont);
1474    }
1475    return *this;
1476}
1477
1478template <class _Container, class _Iter>
1479void
1480__debug_iter<_Container, _Iter>::__set_owner(const __container_type* __c)
1481{
1482    __cont = const_cast<__container_type*>(__c);
1483    __debug_iter*& __head = __cont->__get_iterator_list(this);
1484    __next = __head;
1485    __head = this;
1486}
1487
1488template <class _Container, class _Iter>
1489void
1490__debug_iter<_Container, _Iter>::__remove_owner()
1491{
1492    if (__cont)
1493    {
1494        __debug_iter*& __head = __cont->__get_iterator_list(this);
1495        if (__head == this)
1496            __head = __next;
1497        else
1498        {
1499            __debug_iter* __prev = __head;
1500            for (__debug_iter* __p = __head->__next; __p != this; __p = __p->__next)
1501                __prev = __p;
1502            __prev->__next = __next;
1503        }
1504        __cont = 0;
1505    }
1506}
1507
1508template <class _Container, class _Iter>
1509void
1510__debug_iter<_Container, _Iter>::__remove_all(__container_type* __c)
1511{
1512    __debug_iter*& __head = __c->__get_iterator_list((__debug_iter*)0);
1513    __debug_iter* __p = __head;
1514    __head = 0;
1515    while (__p)
1516    {
1517        __p->__cont = 0;
1518        __debug_iter* __n = __p->__next;
1519        __p->__next = 0;
1520        __p = __n;
1521    }
1522}
1523
1524template <class _Container, class _Iter>
1525void
1526__debug_iter<_Container, _Iter>::swap(__container_type* __x, __container_type* __y)
1527{
1528    __debug_iter*& __head_x = __x->__get_iterator_list((__debug_iter*)0);
1529    __debug_iter*& __head_y = __y->__get_iterator_list((__debug_iter*)0);
1530    __debug_iter* __p = __head_x;
1531    __head_x = __head_y;
1532    __head_y = __p;
1533    for (__p = __head_x; __p; __p = __p->__next)
1534        __p->__cont = __x;
1535    for (__p = __head_y; __p; __p = __p->__next)
1536        __p->__cont = __y;
1537}
1538
1539template <class _Container, class _Iter>
1540bool
1541__debug_iter<_Container, _Iter>::__is_deref(false_type) const
1542{
1543    if (__cont == 0)
1544        return false;
1545    return __i != __cont->end().base();
1546}
1547
1548template <class _Container, class _Iter>
1549bool
1550__debug_iter<_Container, _Iter>::__is_deref(true_type) const
1551{
1552    if (__cont == 0)
1553        return false;
1554    return __i < __cont->end().base();
1555}
1556
1557template <class _Container, class _Iter>
1558bool
1559__debug_iter<_Container, _Iter>::__can_decrement(integral_constant<int, 0>) const
1560{
1561    if (__cont == 0)
1562        return false;
1563    return __i != __cont->begin().base();
1564}
1565
1566template <class _Container, class _Iter>
1567bool
1568__debug_iter<_Container, _Iter>::__can_decrement(integral_constant<int, 1>) const
1569{
1570    if (__cont == 0)
1571        return false;
1572    iterator_type __b = __cont->begin().base();
1573    return __b < __i && __i <= __b + __cont->size();
1574}
1575
1576template <class _Container, class _Iter>
1577bool
1578__debug_iter<_Container, _Iter>::__can_decrement(integral_constant<int, 2>) const
1579{
1580    if (__cont == 0)
1581        return false;
1582    iterator_type __b = __cont->begin().base();
1583    return __b < __i && __i <= __b + __cont->size();
1584}
1585
1586template <class _Container, class _Iter>
1587bool
1588__debug_iter<_Container, _Iter>::__can_increment(integral_constant<int, 0>) const
1589{
1590    if (__cont == 0)
1591        return false;
1592    return __i != __cont->end().base();
1593}
1594
1595template <class _Container, class _Iter>
1596bool
1597__debug_iter<_Container, _Iter>::__can_increment(integral_constant<int, 1>) const
1598{
1599    if (__cont == 0)
1600        return false;
1601    iterator_type __b = __cont->begin().base();
1602    return __b <= __i && __i < __b + __cont->size();
1603}
1604
1605template <class _Container, class _Iter>
1606bool
1607__debug_iter<_Container, _Iter>::__can_increment(integral_constant<int, 2>) const
1608{
1609    if (__cont == 0)
1610        return false;
1611    iterator_type __b = __cont->begin().base();
1612    return __b <= __i && __i < __b + __cont->size();
1613}
1614
1615template <class _Container, class _Iter>
1616bool
1617__debug_iter<_Container, _Iter>::__can_add(difference_type __n, false_type) const
1618{
1619    if (__cont == 0)
1620        return false;
1621    iterator_type __b = __cont->begin().base();
1622    iterator_type __j = __i + __n;
1623    return __b <= __j && __j <= __b + __cont->size();
1624}
1625
1626template <class _Container, class _Iter>
1627bool
1628__debug_iter<_Container, _Iter>::__can_add(difference_type __n, true_type) const
1629{
1630    if (__cont == 0)
1631        return false;
1632    iterator_type __b = __cont->begin().base();
1633    iterator_type __j = __i + __n;
1634    return __b <= __j && __j <= __b + __cont->size();
1635}
1636
1637template <class _Container, class _Iter>
1638__debug_iter<_Container, _Iter>&
1639__debug_iter<_Container, _Iter>::operator+=(difference_type __n)
1640{
1641    assert(__can_add(__n));
1642    __i += __n;
1643    return *this;
1644}
1645
1646template <class _Container, class _Iter1, class _Iter2>
1647inline _LIBCPP_INLINE_VISIBILITY
1648bool
1649operator==(const __debug_iter<_Container, _Iter1>& __x, const __debug_iter<_Container, _Iter2>& __y)
1650{
1651    assert(__x.__cont && __x.__cont == __y.__cont);
1652    return __x.base() == __y.base();
1653}
1654
1655template <class _Container, class _Iter1, class _Iter2>
1656inline _LIBCPP_INLINE_VISIBILITY
1657bool
1658operator!=(const __debug_iter<_Container, _Iter1>& __x, const __debug_iter<_Container, _Iter2>& __y)
1659{
1660    return !(__x == __y);
1661}
1662
1663template <class _Container, class _Iter1, class _Iter2>
1664inline _LIBCPP_INLINE_VISIBILITY
1665bool
1666operator<(const __debug_iter<_Container, _Iter1>& __x, const __debug_iter<_Container, _Iter2>& __y)
1667{
1668    assert(__x.__cont && __x.__cont == __y.__cont);
1669    return __x.base() < __y.base();
1670}
1671
1672template <class _Container, class _Iter1, class _Iter2>
1673inline _LIBCPP_INLINE_VISIBILITY
1674bool
1675operator>(const __debug_iter<_Container, _Iter1>& __x, const __debug_iter<_Container, _Iter2>& __y)
1676{
1677    return __y < __x;
1678}
1679
1680template <class _Container, class _Iter1, class _Iter2>
1681inline _LIBCPP_INLINE_VISIBILITY
1682bool
1683operator>=(const __debug_iter<_Container, _Iter1>& __x, const __debug_iter<_Container, _Iter2>& __y)
1684{
1685    return !(__x < __y);
1686}
1687
1688template <class _Container, class _Iter1, class _Iter2>
1689inline _LIBCPP_INLINE_VISIBILITY
1690bool
1691operator<=(const __debug_iter<_Container, _Iter1>& __x, const __debug_iter<_Container, _Iter2>& __y)
1692{
1693    return !(__y < __x);
1694}
1695
1696template <class _Container, class _Iter1, class _Iter2>
1697inline _LIBCPP_INLINE_VISIBILITY
1698typename __debug_iter<_Container, _Iter1>::difference_type
1699operator-(const __debug_iter<_Container, _Iter1>& __x, const __debug_iter<_Container, _Iter2>& __y)
1700{
1701    assert(__x.__cont && __x.__cont == __y.__cont);
1702    return __x.base() - __y.base();
1703}
1704
1705template <class _Container, class _Iter>
1706inline _LIBCPP_INLINE_VISIBILITY
1707__debug_iter<_Container, _Iter>
1708operator+(typename __debug_iter<_Container, _Iter>::difference_type __n,
1709          const __debug_iter<_Container, _Iter>& __x)
1710{
1711    return __x + __n;
1712}
1713
1714#endif  // _LIBCPP_DEBUG
1715
1716#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_TRAILING_RETURN)
1717
1718template <class _C>
1719inline _LIBCPP_INLINE_VISIBILITY
1720auto
1721begin(_C& __c) -> decltype(__c.begin())
1722{
1723    return __c.begin();
1724}
1725
1726template <class _C>
1727inline _LIBCPP_INLINE_VISIBILITY
1728auto
1729begin(const _C& __c) -> decltype(__c.begin())
1730{
1731    return __c.begin();
1732}
1733
1734template <class _C>
1735inline _LIBCPP_INLINE_VISIBILITY
1736auto
1737end(_C& __c) -> decltype(__c.end())
1738{
1739    return __c.end();
1740}
1741
1742template <class _C>
1743inline _LIBCPP_INLINE_VISIBILITY
1744auto
1745end(const _C& __c) -> decltype(__c.end())
1746{
1747    return __c.end();
1748}
1749
1750#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_TRAILING_RETURN)
1751
1752template <class _C>
1753inline _LIBCPP_INLINE_VISIBILITY
1754typename _C::iterator
1755begin(_C& __c)
1756{
1757    return __c.begin();
1758}
1759
1760template <class _C>
1761inline _LIBCPP_INLINE_VISIBILITY
1762typename _C::const_iterator
1763begin(const _C& __c)
1764{
1765    return __c.begin();
1766}
1767
1768template <class _C>
1769inline _LIBCPP_INLINE_VISIBILITY
1770typename _C::iterator
1771end(_C& __c)
1772{
1773    return __c.end();
1774}
1775
1776template <class _C>
1777inline _LIBCPP_INLINE_VISIBILITY
1778typename _C::const_iterator
1779end(const _C& __c)
1780{
1781    return __c.end();
1782}
1783
1784#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_TRAILING_RETURN)
1785
1786template <class _T, size_t _N>
1787inline _LIBCPP_INLINE_VISIBILITY
1788_T*
1789begin(_T (&__array)[_N])
1790{
1791    return __array;
1792}
1793
1794template <class _T, size_t _N>
1795inline _LIBCPP_INLINE_VISIBILITY
1796_T*
1797end(_T (&__array)[_N])
1798{
1799    return __array + _N;
1800}
1801
1802_LIBCPP_END_NAMESPACE_STD
1803
1804#endif  // _LIBCPP_ITERATOR
1805