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1// -*- C++ -*-
2//===----------------------- forward_list ---------------------------------===//
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_FORWARD_LIST
12#define _LIBCPP_FORWARD_LIST
13
14/*
15    forward_list synopsis
16
17namespace std
18{
19
20template <class T, class Allocator = allocator<T>>
21class forward_list
22{
23public:
24    typedef T         value_type;
25    typedef Allocator allocator_type;
26
27    typedef value_type&                                                reference;
28    typedef const value_type&                                          const_reference;
29    typedef typename allocator_traits<allocator_type>::pointer         pointer;
30    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
31    typedef typename allocator_traits<allocator_type>::size_type       size_type;
32    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
33
34    typedef <details> iterator;
35    typedef <details> const_iterator;
36
37    forward_list()
38        noexcept(is_nothrow_default_constructible<allocator_type>::value);
39    explicit forward_list(const allocator_type& a);
40    explicit forward_list(size_type n);
41    explicit forward_list(size_type n, const allocator_type& a); // C++14
42    forward_list(size_type n, const value_type& v);
43    forward_list(size_type n, const value_type& v, const allocator_type& a);
44    template <class InputIterator>
45        forward_list(InputIterator first, InputIterator last);
46    template <class InputIterator>
47        forward_list(InputIterator first, InputIterator last, const allocator_type& a);
48    forward_list(const forward_list& x);
49    forward_list(const forward_list& x, const allocator_type& a);
50    forward_list(forward_list&& x)
51        noexcept(is_nothrow_move_constructible<allocator_type>::value);
52    forward_list(forward_list&& x, const allocator_type& a);
53    forward_list(initializer_list<value_type> il);
54    forward_list(initializer_list<value_type> il, const allocator_type& a);
55
56    ~forward_list();
57
58    forward_list& operator=(const forward_list& x);
59    forward_list& operator=(forward_list&& x)
60        noexcept(
61             allocator_type::propagate_on_container_move_assignment::value &&
62             is_nothrow_move_assignable<allocator_type>::value);
63    forward_list& operator=(initializer_list<value_type> il);
64
65    template <class InputIterator>
66        void assign(InputIterator first, InputIterator last);
67    void assign(size_type n, const value_type& v);
68    void assign(initializer_list<value_type> il);
69
70    allocator_type get_allocator() const noexcept;
71
72    iterator       begin() noexcept;
73    const_iterator begin() const noexcept;
74    iterator       end() noexcept;
75    const_iterator end() const noexcept;
76
77    const_iterator cbegin() const noexcept;
78    const_iterator cend() const noexcept;
79
80    iterator       before_begin() noexcept;
81    const_iterator before_begin() const noexcept;
82    const_iterator cbefore_begin() const noexcept;
83
84    bool empty() const noexcept;
85    size_type max_size() const noexcept;
86
87    reference       front();
88    const_reference front() const;
89
90    template <class... Args> reference emplace_front(Args&&... args);  // reference in C++17
91    void push_front(const value_type& v);
92    void push_front(value_type&& v);
93
94    void pop_front();
95
96    template <class... Args>
97        iterator emplace_after(const_iterator p, Args&&... args);
98    iterator insert_after(const_iterator p, const value_type& v);
99    iterator insert_after(const_iterator p, value_type&& v);
100    iterator insert_after(const_iterator p, size_type n, const value_type& v);
101    template <class InputIterator>
102        iterator insert_after(const_iterator p,
103                              InputIterator first, InputIterator last);
104    iterator insert_after(const_iterator p, initializer_list<value_type> il);
105
106    iterator erase_after(const_iterator p);
107    iterator erase_after(const_iterator first, const_iterator last);
108
109    void swap(forward_list& x)
110        noexcept(allocator_traits<allocator_type>::is_always_equal::value);  // C++17
111
112    void resize(size_type n);
113    void resize(size_type n, const value_type& v);
114    void clear() noexcept;
115
116    void splice_after(const_iterator p, forward_list& x);
117    void splice_after(const_iterator p, forward_list&& x);
118    void splice_after(const_iterator p, forward_list& x, const_iterator i);
119    void splice_after(const_iterator p, forward_list&& x, const_iterator i);
120    void splice_after(const_iterator p, forward_list& x,
121                      const_iterator first, const_iterator last);
122    void splice_after(const_iterator p, forward_list&& x,
123                      const_iterator first, const_iterator last);
124    void remove(const value_type& v);
125    template <class Predicate> void remove_if(Predicate pred);
126    void unique();
127    template <class BinaryPredicate> void unique(BinaryPredicate binary_pred);
128    void merge(forward_list& x);
129    void merge(forward_list&& x);
130    template <class Compare> void merge(forward_list& x, Compare comp);
131    template <class Compare> void merge(forward_list&& x, Compare comp);
132    void sort();
133    template <class Compare> void sort(Compare comp);
134    void reverse() noexcept;
135};
136
137template <class T, class Allocator>
138    bool operator==(const forward_list<T, Allocator>& x,
139                    const forward_list<T, Allocator>& y);
140
141template <class T, class Allocator>
142    bool operator< (const forward_list<T, Allocator>& x,
143                    const forward_list<T, Allocator>& y);
144
145template <class T, class Allocator>
146    bool operator!=(const forward_list<T, Allocator>& x,
147                    const forward_list<T, Allocator>& y);
148
149template <class T, class Allocator>
150    bool operator> (const forward_list<T, Allocator>& x,
151                    const forward_list<T, Allocator>& y);
152
153template <class T, class Allocator>
154    bool operator>=(const forward_list<T, Allocator>& x,
155                    const forward_list<T, Allocator>& y);
156
157template <class T, class Allocator>
158    bool operator<=(const forward_list<T, Allocator>& x,
159                    const forward_list<T, Allocator>& y);
160
161template <class T, class Allocator>
162    void swap(forward_list<T, Allocator>& x, forward_list<T, Allocator>& y)
163         noexcept(noexcept(x.swap(y)));
164
165}  // std
166
167*/
168
169#include <__config>
170
171#include <initializer_list>
172#include <memory>
173#include <limits>
174#include <iterator>
175#include <algorithm>
176
177#include <__undef_min_max>
178
179#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
180#pragma GCC system_header
181#endif
182
183_LIBCPP_BEGIN_NAMESPACE_STD
184
185template <class _Tp, class _VoidPtr> struct __forward_list_node;
186template <class _NodePtr> struct __forward_begin_node;
187
188
189template <class>
190struct __forward_list_node_value_type;
191
192template <class _Tp, class _VoidPtr>
193struct __forward_list_node_value_type<__forward_list_node<_Tp, _VoidPtr> > {
194  typedef _Tp type;
195};
196
197template <class _NodePtr>
198struct __forward_node_traits {
199
200  typedef typename remove_cv<
201        typename pointer_traits<_NodePtr>::element_type>::type  __node;
202  typedef typename __forward_list_node_value_type<__node>::type __node_value_type;
203  typedef _NodePtr                                              __node_pointer;
204  typedef __forward_begin_node<_NodePtr>                        __begin_node;
205  typedef typename __rebind_pointer<_NodePtr, __begin_node>::type
206                                                                __begin_node_pointer;
207  typedef typename __rebind_pointer<_NodePtr, void>::type       __void_pointer;
208
209#if defined(_LIBCPP_ABI_FORWARD_LIST_REMOVE_NODE_POINTER_UB)
210  typedef __begin_node_pointer __iter_node_pointer;
211#else
212  typedef typename conditional<
213          is_pointer<__void_pointer>::value,
214          __begin_node_pointer,
215          __node_pointer
216    >::type __iter_node_pointer;
217#endif
218
219  typedef typename conditional<
220          is_same<__iter_node_pointer, __node_pointer>::value,
221          __begin_node_pointer,
222          __node_pointer
223    >::type __non_iter_node_pointer;
224
225  _LIBCPP_INLINE_VISIBILITY
226  static __iter_node_pointer __as_iter_node(__iter_node_pointer __p) {
227      return __p;
228  }
229  _LIBCPP_INLINE_VISIBILITY
230  static __iter_node_pointer __as_iter_node(__non_iter_node_pointer __p) {
231      return static_cast<__iter_node_pointer>(static_cast<__void_pointer>(__p));
232  }
233};
234
235template <class _NodePtr>
236struct __forward_begin_node
237{
238    typedef _NodePtr pointer;
239    typedef typename __rebind_pointer<_NodePtr, __forward_begin_node>::type __begin_node_pointer;
240
241    pointer __next_;
242
243    _LIBCPP_INLINE_VISIBILITY __forward_begin_node() : __next_(nullptr) {}
244
245    _LIBCPP_INLINE_VISIBILITY
246    __begin_node_pointer __next_as_begin() const {
247        return static_cast<__begin_node_pointer>(__next_);
248    }
249};
250
251template <class _Tp, class _VoidPtr>
252struct _LIBCPP_HIDDEN __begin_node_of
253{
254    typedef __forward_begin_node<
255        typename __rebind_pointer<_VoidPtr, __forward_list_node<_Tp, _VoidPtr> >::type
256    > type;
257};
258
259template <class _Tp, class _VoidPtr>
260struct __forward_list_node
261    : public __begin_node_of<_Tp, _VoidPtr>::type
262{
263    typedef _Tp value_type;
264
265    value_type __value_;
266};
267
268
269template <class _Tp, class _Alloc = allocator<_Tp> > class _LIBCPP_TEMPLATE_VIS forward_list;
270template<class _NodeConstPtr> class _LIBCPP_TEMPLATE_VIS __forward_list_const_iterator;
271
272template <class _NodePtr>
273class _LIBCPP_TEMPLATE_VIS __forward_list_iterator
274{
275    typedef __forward_node_traits<_NodePtr>         __traits;
276    typedef typename __traits::__node_pointer       __node_pointer;
277    typedef typename __traits::__begin_node_pointer __begin_node_pointer;
278    typedef typename __traits::__iter_node_pointer  __iter_node_pointer;
279    typedef typename __traits::__void_pointer       __void_pointer;
280
281    __iter_node_pointer __ptr_;
282
283    _LIBCPP_INLINE_VISIBILITY
284    __begin_node_pointer __get_begin() const {
285        return static_cast<__begin_node_pointer>(
286                static_cast<__void_pointer>(__ptr_));
287    }
288    _LIBCPP_INLINE_VISIBILITY
289    __node_pointer __get_unsafe_node_pointer() const {
290        return static_cast<__node_pointer>(
291                static_cast<__void_pointer>(__ptr_));
292    }
293
294    _LIBCPP_INLINE_VISIBILITY
295    explicit __forward_list_iterator(nullptr_t) _NOEXCEPT : __ptr_(nullptr) {}
296
297    _LIBCPP_INLINE_VISIBILITY
298    explicit __forward_list_iterator(__begin_node_pointer __p) _NOEXCEPT
299        : __ptr_(__traits::__as_iter_node(__p)) {}
300
301    _LIBCPP_INLINE_VISIBILITY
302    explicit __forward_list_iterator(__node_pointer __p) _NOEXCEPT
303        : __ptr_(__traits::__as_iter_node(__p)) {}
304
305    template<class, class> friend class _LIBCPP_TEMPLATE_VIS forward_list;
306    template<class> friend class _LIBCPP_TEMPLATE_VIS __forward_list_const_iterator;
307
308public:
309    typedef forward_iterator_tag                              iterator_category;
310    typedef typename __traits::__node_value_type              value_type;
311    typedef value_type&                                       reference;
312    typedef typename pointer_traits<__node_pointer>::difference_type
313                                                              difference_type;
314    typedef typename __rebind_pointer<__node_pointer, value_type>::type pointer;
315
316    _LIBCPP_INLINE_VISIBILITY
317    __forward_list_iterator() _NOEXCEPT : __ptr_(nullptr) {}
318
319    _LIBCPP_INLINE_VISIBILITY
320    reference operator*() const {return __get_unsafe_node_pointer()->__value_;}
321    _LIBCPP_INLINE_VISIBILITY
322    pointer operator->() const {
323        return pointer_traits<pointer>::pointer_to(__get_unsafe_node_pointer()->__value_);
324    }
325
326    _LIBCPP_INLINE_VISIBILITY
327    __forward_list_iterator& operator++()
328    {
329        __ptr_ = __traits::__as_iter_node(__ptr_->__next_);
330        return *this;
331    }
332    _LIBCPP_INLINE_VISIBILITY
333    __forward_list_iterator operator++(int)
334    {
335        __forward_list_iterator __t(*this);
336        ++(*this);
337        return __t;
338    }
339
340    friend _LIBCPP_INLINE_VISIBILITY
341    bool operator==(const __forward_list_iterator& __x,
342                    const __forward_list_iterator& __y)
343        {return __x.__ptr_ == __y.__ptr_;}
344    friend _LIBCPP_INLINE_VISIBILITY
345    bool operator!=(const __forward_list_iterator& __x,
346                    const __forward_list_iterator& __y)
347        {return !(__x == __y);}
348};
349
350template <class _NodeConstPtr>
351class _LIBCPP_TEMPLATE_VIS __forward_list_const_iterator
352{
353    static_assert((!is_const<typename pointer_traits<_NodeConstPtr>::element_type>::value), "");
354    typedef _NodeConstPtr _NodePtr;
355
356    typedef __forward_node_traits<_NodePtr>         __traits;
357    typedef typename __traits::__node               __node;
358    typedef typename __traits::__node_pointer       __node_pointer;
359    typedef typename __traits::__begin_node_pointer __begin_node_pointer;
360    typedef typename __traits::__iter_node_pointer  __iter_node_pointer;
361    typedef typename __traits::__void_pointer       __void_pointer;
362
363    __iter_node_pointer __ptr_;
364
365    __begin_node_pointer __get_begin() const {
366        return static_cast<__begin_node_pointer>(
367                static_cast<__void_pointer>(__ptr_));
368    }
369    __node_pointer __get_unsafe_node_pointer() const {
370        return static_cast<__node_pointer>(
371                static_cast<__void_pointer>(__ptr_));
372    }
373
374    _LIBCPP_INLINE_VISIBILITY
375    explicit __forward_list_const_iterator(nullptr_t) _NOEXCEPT
376        : __ptr_(nullptr) {}
377
378    _LIBCPP_INLINE_VISIBILITY
379    explicit __forward_list_const_iterator(__begin_node_pointer __p) _NOEXCEPT
380        : __ptr_(__traits::__as_iter_node(__p)) {}
381
382    _LIBCPP_INLINE_VISIBILITY
383    explicit __forward_list_const_iterator(__node_pointer __p) _NOEXCEPT
384        : __ptr_(__traits::__as_iter_node(__p)) {}
385
386
387    template<class, class> friend class forward_list;
388
389public:
390    typedef forward_iterator_tag                              iterator_category;
391    typedef typename __traits::__node_value_type              value_type;
392    typedef const value_type&                                 reference;
393    typedef typename pointer_traits<__node_pointer>::difference_type
394                                                              difference_type;
395    typedef typename __rebind_pointer<__node_pointer, const value_type>::type
396                                                              pointer;
397
398    _LIBCPP_INLINE_VISIBILITY
399    __forward_list_const_iterator() _NOEXCEPT : __ptr_(nullptr) {}
400    _LIBCPP_INLINE_VISIBILITY
401    __forward_list_const_iterator(__forward_list_iterator<__node_pointer> __p) _NOEXCEPT
402        : __ptr_(__p.__ptr_) {}
403
404    _LIBCPP_INLINE_VISIBILITY
405    reference operator*() const {return __get_unsafe_node_pointer()->__value_;}
406    _LIBCPP_INLINE_VISIBILITY
407    pointer operator->() const {return pointer_traits<pointer>::pointer_to(
408                __get_unsafe_node_pointer()->__value_);}
409
410    _LIBCPP_INLINE_VISIBILITY
411    __forward_list_const_iterator& operator++()
412    {
413        __ptr_ = __traits::__as_iter_node(__ptr_->__next_);
414        return *this;
415    }
416    _LIBCPP_INLINE_VISIBILITY
417    __forward_list_const_iterator operator++(int)
418    {
419        __forward_list_const_iterator __t(*this);
420        ++(*this);
421        return __t;
422    }
423
424    friend _LIBCPP_INLINE_VISIBILITY
425    bool operator==(const __forward_list_const_iterator& __x,
426                    const __forward_list_const_iterator& __y)
427        {return __x.__ptr_ == __y.__ptr_;}
428    friend _LIBCPP_INLINE_VISIBILITY
429    bool operator!=(const __forward_list_const_iterator& __x,
430                           const __forward_list_const_iterator& __y)
431        {return !(__x == __y);}
432};
433
434template <class _Tp, class _Alloc>
435class __forward_list_base
436{
437protected:
438    typedef _Tp    value_type;
439    typedef _Alloc allocator_type;
440
441    typedef typename allocator_traits<allocator_type>::void_pointer  void_pointer;
442    typedef __forward_list_node<value_type, void_pointer>            __node;
443    typedef typename __begin_node_of<value_type, void_pointer>::type __begin_node;
444    typedef typename __rebind_alloc_helper<allocator_traits<allocator_type>, __node>::type __node_allocator;
445    typedef allocator_traits<__node_allocator>        __node_traits;
446    typedef typename __node_traits::pointer           __node_pointer;
447
448    typedef typename __rebind_alloc_helper<
449        allocator_traits<allocator_type>, __begin_node
450    >::type                                           __begin_node_allocator;
451    typedef typename allocator_traits<__begin_node_allocator>::pointer
452                                                      __begin_node_pointer;
453
454    __compressed_pair<__begin_node, __node_allocator> __before_begin_;
455
456    _LIBCPP_INLINE_VISIBILITY
457    __begin_node_pointer        __before_begin() _NOEXCEPT
458        {return pointer_traits<__begin_node_pointer>::pointer_to(__before_begin_.first());}
459    _LIBCPP_INLINE_VISIBILITY
460    __begin_node_pointer __before_begin() const _NOEXCEPT
461        {return pointer_traits<__begin_node_pointer>::pointer_to(const_cast<__begin_node&>(__before_begin_.first()));}
462
463    _LIBCPP_INLINE_VISIBILITY
464          __node_allocator& __alloc() _NOEXCEPT
465            {return __before_begin_.second();}
466    _LIBCPP_INLINE_VISIBILITY
467    const __node_allocator& __alloc() const _NOEXCEPT
468        {return __before_begin_.second();}
469
470    typedef __forward_list_iterator<__node_pointer>             iterator;
471    typedef __forward_list_const_iterator<__node_pointer>       const_iterator;
472
473    _LIBCPP_INLINE_VISIBILITY
474    __forward_list_base()
475        _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value)
476        : __before_begin_(__begin_node()) {}
477    _LIBCPP_INLINE_VISIBILITY
478    __forward_list_base(const allocator_type& __a)
479        : __before_begin_(__begin_node(), __node_allocator(__a)) {}
480
481#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
482public:
483    _LIBCPP_INLINE_VISIBILITY
484    __forward_list_base(__forward_list_base&& __x)
485        _NOEXCEPT_(is_nothrow_move_constructible<__node_allocator>::value);
486    _LIBCPP_INLINE_VISIBILITY
487    __forward_list_base(__forward_list_base&& __x, const allocator_type& __a);
488#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
489
490private:
491    __forward_list_base(const __forward_list_base&);
492    __forward_list_base& operator=(const __forward_list_base&);
493
494public:
495    ~__forward_list_base();
496
497protected:
498    _LIBCPP_INLINE_VISIBILITY
499    void __copy_assign_alloc(const __forward_list_base& __x)
500        {__copy_assign_alloc(__x, integral_constant<bool,
501              __node_traits::propagate_on_container_copy_assignment::value>());}
502
503    _LIBCPP_INLINE_VISIBILITY
504    void __move_assign_alloc(__forward_list_base& __x)
505        _NOEXCEPT_(!__node_traits::propagate_on_container_move_assignment::value ||
506                   is_nothrow_move_assignable<__node_allocator>::value)
507        {__move_assign_alloc(__x, integral_constant<bool,
508              __node_traits::propagate_on_container_move_assignment::value>());}
509
510public:
511    _LIBCPP_INLINE_VISIBILITY
512    void swap(__forward_list_base& __x)
513#if _LIBCPP_STD_VER >= 14
514        _NOEXCEPT;
515#else
516        _NOEXCEPT_(!__node_traits::propagate_on_container_move_assignment::value ||
517                    __is_nothrow_swappable<__node_allocator>::value);
518#endif
519protected:
520    void clear() _NOEXCEPT;
521
522private:
523    _LIBCPP_INLINE_VISIBILITY
524    void __copy_assign_alloc(const __forward_list_base&, false_type) {}
525    _LIBCPP_INLINE_VISIBILITY
526    void __copy_assign_alloc(const __forward_list_base& __x, true_type)
527    {
528        if (__alloc() != __x.__alloc())
529            clear();
530        __alloc() = __x.__alloc();
531    }
532
533    _LIBCPP_INLINE_VISIBILITY
534    void __move_assign_alloc(__forward_list_base&, false_type) _NOEXCEPT
535        {}
536    _LIBCPP_INLINE_VISIBILITY
537    void __move_assign_alloc(__forward_list_base& __x, true_type)
538        _NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value)
539        {__alloc() = _VSTD::move(__x.__alloc());}
540};
541
542#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
543
544template <class _Tp, class _Alloc>
545inline
546__forward_list_base<_Tp, _Alloc>::__forward_list_base(__forward_list_base&& __x)
547        _NOEXCEPT_(is_nothrow_move_constructible<__node_allocator>::value)
548    : __before_begin_(_VSTD::move(__x.__before_begin_))
549{
550    __x.__before_begin()->__next_ = nullptr;
551}
552
553template <class _Tp, class _Alloc>
554inline
555__forward_list_base<_Tp, _Alloc>::__forward_list_base(__forward_list_base&& __x,
556                                                      const allocator_type& __a)
557    : __before_begin_(__begin_node(), __node_allocator(__a))
558{
559    if (__alloc() == __x.__alloc())
560    {
561        __before_begin()->__next_ = __x.__before_begin()->__next_;
562        __x.__before_begin()->__next_ = nullptr;
563    }
564}
565
566#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
567
568template <class _Tp, class _Alloc>
569__forward_list_base<_Tp, _Alloc>::~__forward_list_base()
570{
571    clear();
572}
573
574template <class _Tp, class _Alloc>
575inline
576void
577__forward_list_base<_Tp, _Alloc>::swap(__forward_list_base& __x)
578#if _LIBCPP_STD_VER >= 14
579        _NOEXCEPT
580#else
581        _NOEXCEPT_(!__node_traits::propagate_on_container_move_assignment::value ||
582                    __is_nothrow_swappable<__node_allocator>::value)
583#endif
584{
585    __swap_allocator(__alloc(), __x.__alloc(),
586            integral_constant<bool, __node_traits::propagate_on_container_swap::value>());
587    using _VSTD::swap;
588    swap(__before_begin()->__next_, __x.__before_begin()->__next_);
589}
590
591template <class _Tp, class _Alloc>
592void
593__forward_list_base<_Tp, _Alloc>::clear() _NOEXCEPT
594{
595    __node_allocator& __a = __alloc();
596    for (__node_pointer __p = __before_begin()->__next_; __p != nullptr;)
597    {
598        __node_pointer __next = __p->__next_;
599        __node_traits::destroy(__a, _VSTD::addressof(__p->__value_));
600        __node_traits::deallocate(__a, __p, 1);
601        __p = __next;
602    }
603    __before_begin()->__next_ = nullptr;
604}
605
606template <class _Tp, class _Alloc /*= allocator<_Tp>*/>
607class _LIBCPP_TEMPLATE_VIS forward_list
608    : private __forward_list_base<_Tp, _Alloc>
609{
610    typedef __forward_list_base<_Tp, _Alloc> base;
611    typedef typename base::__node_allocator  __node_allocator;
612    typedef typename base::__node               __node;
613    typedef typename base::__node_traits        __node_traits;
614    typedef typename base::__node_pointer       __node_pointer;
615    typedef typename base::__begin_node_pointer __begin_node_pointer;
616
617public:
618    typedef _Tp    value_type;
619    typedef _Alloc allocator_type;
620
621    static_assert((is_same<typename allocator_type::value_type, value_type>::value),
622                  "Allocator::value_type must be same type as value_type");
623
624    typedef value_type&                                                reference;
625    typedef const value_type&                                          const_reference;
626    typedef typename allocator_traits<allocator_type>::pointer         pointer;
627    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
628    typedef typename allocator_traits<allocator_type>::size_type       size_type;
629    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
630
631    typedef typename base::iterator       iterator;
632    typedef typename base::const_iterator const_iterator;
633
634    _LIBCPP_INLINE_VISIBILITY
635    forward_list()
636        _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value)
637        {} // = default;
638    _LIBCPP_INLINE_VISIBILITY
639    explicit forward_list(const allocator_type& __a);
640    explicit forward_list(size_type __n);
641#if _LIBCPP_STD_VER > 11
642    explicit forward_list(size_type __n, const allocator_type& __a);
643#endif
644    forward_list(size_type __n, const value_type& __v);
645    forward_list(size_type __n, const value_type& __v, const allocator_type& __a);
646    template <class _InputIterator>
647        forward_list(_InputIterator __f, _InputIterator __l,
648                     typename enable_if<
649                       __is_input_iterator<_InputIterator>::value
650                     >::type* = nullptr);
651    template <class _InputIterator>
652        forward_list(_InputIterator __f, _InputIterator __l,
653                     const allocator_type& __a,
654                     typename enable_if<
655                       __is_input_iterator<_InputIterator>::value
656                     >::type* = nullptr);
657    forward_list(const forward_list& __x);
658    forward_list(const forward_list& __x, const allocator_type& __a);
659#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
660    _LIBCPP_INLINE_VISIBILITY
661    forward_list(forward_list&& __x)
662        _NOEXCEPT_(is_nothrow_move_constructible<base>::value)
663        : base(_VSTD::move(__x)) {}
664    forward_list(forward_list&& __x, const allocator_type& __a);
665#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
666#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
667    forward_list(initializer_list<value_type> __il);
668    forward_list(initializer_list<value_type> __il, const allocator_type& __a);
669#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
670
671    // ~forward_list() = default;
672
673    forward_list& operator=(const forward_list& __x);
674#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
675    _LIBCPP_INLINE_VISIBILITY
676    forward_list& operator=(forward_list&& __x)
677        _NOEXCEPT_(
678             __node_traits::propagate_on_container_move_assignment::value &&
679             is_nothrow_move_assignable<allocator_type>::value);
680#endif
681#ifndef  _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
682    _LIBCPP_INLINE_VISIBILITY
683    forward_list& operator=(initializer_list<value_type> __il);
684#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
685
686    template <class _InputIterator>
687        typename enable_if
688        <
689            __is_input_iterator<_InputIterator>::value,
690            void
691        >::type
692        assign(_InputIterator __f, _InputIterator __l);
693    void assign(size_type __n, const value_type& __v);
694#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
695    _LIBCPP_INLINE_VISIBILITY
696    void assign(initializer_list<value_type> __il);
697#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
698
699    _LIBCPP_INLINE_VISIBILITY
700    allocator_type get_allocator() const _NOEXCEPT
701        {return allocator_type(base::__alloc());}
702
703    _LIBCPP_INLINE_VISIBILITY
704    iterator       begin() _NOEXCEPT
705        {return       iterator(base::__before_begin()->__next_);}
706    _LIBCPP_INLINE_VISIBILITY
707    const_iterator begin() const _NOEXCEPT
708        {return const_iterator(base::__before_begin()->__next_);}
709    _LIBCPP_INLINE_VISIBILITY
710    iterator       end() _NOEXCEPT
711        {return       iterator(nullptr);}
712    _LIBCPP_INLINE_VISIBILITY
713    const_iterator end() const _NOEXCEPT
714        {return const_iterator(nullptr);}
715
716    _LIBCPP_INLINE_VISIBILITY
717    const_iterator cbegin() const _NOEXCEPT
718        {return const_iterator(base::__before_begin()->__next_);}
719    _LIBCPP_INLINE_VISIBILITY
720    const_iterator cend() const _NOEXCEPT
721        {return const_iterator(nullptr);}
722
723    _LIBCPP_INLINE_VISIBILITY
724    iterator       before_begin() _NOEXCEPT
725        {return       iterator(base::__before_begin());}
726    _LIBCPP_INLINE_VISIBILITY
727    const_iterator before_begin() const _NOEXCEPT
728        {return const_iterator(base::__before_begin());}
729    _LIBCPP_INLINE_VISIBILITY
730    const_iterator cbefore_begin() const _NOEXCEPT
731        {return const_iterator(base::__before_begin());}
732
733    _LIBCPP_INLINE_VISIBILITY
734    bool empty() const _NOEXCEPT
735        {return base::__before_begin()->__next_ == nullptr;}
736    _LIBCPP_INLINE_VISIBILITY
737    size_type max_size() const _NOEXCEPT {
738        return std::min<size_type>(
739            __node_traits::max_size(base::__alloc()),
740            numeric_limits<difference_type>::max());
741    }
742
743    _LIBCPP_INLINE_VISIBILITY
744    reference       front()       {return base::__before_begin()->__next_->__value_;}
745    _LIBCPP_INLINE_VISIBILITY
746    const_reference front() const {return base::__before_begin()->__next_->__value_;}
747
748#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
749#ifndef _LIBCPP_HAS_NO_VARIADICS
750#if _LIBCPP_STD_VER > 14
751    template <class... _Args> reference emplace_front(_Args&&... __args);
752#else
753    template <class... _Args> void      emplace_front(_Args&&... __args);
754#endif
755#endif
756    void push_front(value_type&& __v);
757#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
758    void push_front(const value_type& __v);
759
760    void pop_front();
761
762#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
763#ifndef _LIBCPP_HAS_NO_VARIADICS
764    template <class... _Args>
765        iterator emplace_after(const_iterator __p, _Args&&... __args);
766#endif  // _LIBCPP_HAS_NO_VARIADICS
767    iterator insert_after(const_iterator __p, value_type&& __v);
768#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
769    iterator insert_after(const_iterator __p, const value_type& __v);
770    iterator insert_after(const_iterator __p, size_type __n, const value_type& __v);
771    template <class _InputIterator>
772        _LIBCPP_INLINE_VISIBILITY
773        typename enable_if
774        <
775            __is_input_iterator<_InputIterator>::value,
776            iterator
777        >::type
778        insert_after(const_iterator __p, _InputIterator __f, _InputIterator __l);
779#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
780    iterator insert_after(const_iterator __p, initializer_list<value_type> __il)
781        {return insert_after(__p, __il.begin(), __il.end());}
782#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
783
784    iterator erase_after(const_iterator __p);
785    iterator erase_after(const_iterator __f, const_iterator __l);
786
787    _LIBCPP_INLINE_VISIBILITY
788    void swap(forward_list& __x)
789#if _LIBCPP_STD_VER >= 14
790        _NOEXCEPT
791#else
792        _NOEXCEPT_(!__node_traits::propagate_on_container_swap::value ||
793                   __is_nothrow_swappable<__node_allocator>::value)
794#endif
795        {base::swap(__x);}
796
797    void resize(size_type __n);
798    void resize(size_type __n, const value_type& __v);
799    _LIBCPP_INLINE_VISIBILITY
800    void clear() _NOEXCEPT {base::clear();}
801
802#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
803    _LIBCPP_INLINE_VISIBILITY
804    void splice_after(const_iterator __p, forward_list&& __x);
805    _LIBCPP_INLINE_VISIBILITY
806    void splice_after(const_iterator __p, forward_list&& __x, const_iterator __i);
807    _LIBCPP_INLINE_VISIBILITY
808    void splice_after(const_iterator __p, forward_list&& __x,
809                      const_iterator __f, const_iterator __l);
810#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
811    void splice_after(const_iterator __p, forward_list& __x);
812    void splice_after(const_iterator __p, forward_list& __x, const_iterator __i);
813    void splice_after(const_iterator __p, forward_list& __x,
814                      const_iterator __f, const_iterator __l);
815    void remove(const value_type& __v);
816    template <class _Predicate> void remove_if(_Predicate __pred);
817    _LIBCPP_INLINE_VISIBILITY
818    void unique() {unique(__equal_to<value_type>());}
819    template <class _BinaryPredicate> void unique(_BinaryPredicate __binary_pred);
820#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
821    _LIBCPP_INLINE_VISIBILITY
822    void merge(forward_list&& __x) {merge(__x, __less<value_type>());}
823    template <class _Compare>
824        _LIBCPP_INLINE_VISIBILITY
825        void merge(forward_list&& __x, _Compare __comp)
826        {merge(__x, _VSTD::move(__comp));}
827#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
828    _LIBCPP_INLINE_VISIBILITY
829    void merge(forward_list& __x) {merge(__x, __less<value_type>());}
830    template <class _Compare> void merge(forward_list& __x, _Compare __comp);
831    _LIBCPP_INLINE_VISIBILITY
832    void sort() {sort(__less<value_type>());}
833    template <class _Compare> _LIBCPP_INLINE_VISIBILITY void sort(_Compare __comp);
834    void reverse() _NOEXCEPT;
835
836private:
837
838#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
839    void __move_assign(forward_list& __x, true_type)
840        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
841    void __move_assign(forward_list& __x, false_type);
842#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
843
844    template <class _Compare>
845        static
846        __node_pointer
847        __merge(__node_pointer __f1, __node_pointer __f2, _Compare& __comp);
848
849    template <class _Compare>
850        static
851        __node_pointer
852        __sort(__node_pointer __f, difference_type __sz, _Compare& __comp);
853};
854
855template <class _Tp, class _Alloc>
856inline
857forward_list<_Tp, _Alloc>::forward_list(const allocator_type& __a)
858    : base(__a)
859{
860}
861
862template <class _Tp, class _Alloc>
863forward_list<_Tp, _Alloc>::forward_list(size_type __n)
864{
865    if (__n > 0)
866    {
867        __node_allocator& __a = base::__alloc();
868        typedef __allocator_destructor<__node_allocator> _Dp;
869        unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
870        for (__begin_node_pointer __p = base::__before_begin(); __n > 0; --__n,
871                                                             __p = __p->__next_as_begin())
872        {
873            __h.reset(__node_traits::allocate(__a, 1));
874            __node_traits::construct(__a, _VSTD::addressof(__h->__value_));
875            __h->__next_ = nullptr;
876            __p->__next_ = __h.release();
877        }
878    }
879}
880
881#if _LIBCPP_STD_VER > 11
882template <class _Tp, class _Alloc>
883forward_list<_Tp, _Alloc>::forward_list(size_type __n,
884                                        const allocator_type& __base_alloc)
885    : base ( __base_alloc )
886{
887    if (__n > 0)
888    {
889        __node_allocator& __a = base::__alloc();
890        typedef __allocator_destructor<__node_allocator> _Dp;
891        unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
892        for (__begin_node_pointer __p = base::__before_begin(); __n > 0; --__n,
893                                                             __p = __p->__next_as_begin())
894        {
895            __h.reset(__node_traits::allocate(__a, 1));
896            __node_traits::construct(__a, _VSTD::addressof(__h->__value_));
897            __h->__next_ = nullptr;
898            __p->__next_ = __h.release();
899        }
900    }
901}
902#endif
903
904template <class _Tp, class _Alloc>
905forward_list<_Tp, _Alloc>::forward_list(size_type __n, const value_type& __v)
906{
907    insert_after(cbefore_begin(), __n, __v);
908}
909
910template <class _Tp, class _Alloc>
911forward_list<_Tp, _Alloc>::forward_list(size_type __n, const value_type& __v,
912                                        const allocator_type& __a)
913    : base(__a)
914{
915    insert_after(cbefore_begin(), __n, __v);
916}
917
918template <class _Tp, class _Alloc>
919template <class _InputIterator>
920forward_list<_Tp, _Alloc>::forward_list(_InputIterator __f, _InputIterator __l,
921                                        typename enable_if<
922                                          __is_input_iterator<_InputIterator>::value
923                                        >::type*)
924{
925    insert_after(cbefore_begin(), __f, __l);
926}
927
928template <class _Tp, class _Alloc>
929template <class _InputIterator>
930forward_list<_Tp, _Alloc>::forward_list(_InputIterator __f, _InputIterator __l,
931                                        const allocator_type& __a,
932                                        typename enable_if<
933                                          __is_input_iterator<_InputIterator>::value
934                                        >::type*)
935    : base(__a)
936{
937    insert_after(cbefore_begin(), __f, __l);
938}
939
940template <class _Tp, class _Alloc>
941forward_list<_Tp, _Alloc>::forward_list(const forward_list& __x)
942    : base(allocator_type(
943             __node_traits::select_on_container_copy_construction(__x.__alloc())
944                         )
945          )
946{
947    insert_after(cbefore_begin(), __x.begin(), __x.end());
948}
949
950template <class _Tp, class _Alloc>
951forward_list<_Tp, _Alloc>::forward_list(const forward_list& __x,
952                                        const allocator_type& __a)
953    : base(__a)
954{
955    insert_after(cbefore_begin(), __x.begin(), __x.end());
956}
957
958#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
959
960template <class _Tp, class _Alloc>
961forward_list<_Tp, _Alloc>::forward_list(forward_list&& __x,
962                                        const allocator_type& __a)
963    : base(_VSTD::move(__x), __a)
964{
965    if (base::__alloc() != __x.__alloc())
966    {
967        typedef move_iterator<iterator> _Ip;
968        insert_after(cbefore_begin(), _Ip(__x.begin()), _Ip(__x.end()));
969    }
970}
971
972#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
973
974#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
975
976template <class _Tp, class _Alloc>
977forward_list<_Tp, _Alloc>::forward_list(initializer_list<value_type> __il)
978{
979    insert_after(cbefore_begin(), __il.begin(), __il.end());
980}
981
982template <class _Tp, class _Alloc>
983forward_list<_Tp, _Alloc>::forward_list(initializer_list<value_type> __il,
984                                        const allocator_type& __a)
985    : base(__a)
986{
987    insert_after(cbefore_begin(), __il.begin(), __il.end());
988}
989
990#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
991
992template <class _Tp, class _Alloc>
993forward_list<_Tp, _Alloc>&
994forward_list<_Tp, _Alloc>::operator=(const forward_list& __x)
995{
996    if (this != &__x)
997    {
998        base::__copy_assign_alloc(__x);
999        assign(__x.begin(), __x.end());
1000    }
1001    return *this;
1002}
1003
1004#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1005
1006template <class _Tp, class _Alloc>
1007void
1008forward_list<_Tp, _Alloc>::__move_assign(forward_list& __x, true_type)
1009    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1010{
1011    clear();
1012    base::__move_assign_alloc(__x);
1013    base::__before_begin()->__next_ = __x.__before_begin()->__next_;
1014    __x.__before_begin()->__next_ = nullptr;
1015}
1016
1017template <class _Tp, class _Alloc>
1018void
1019forward_list<_Tp, _Alloc>::__move_assign(forward_list& __x, false_type)
1020{
1021    if (base::__alloc() == __x.__alloc())
1022        __move_assign(__x, true_type());
1023    else
1024    {
1025        typedef move_iterator<iterator> _Ip;
1026        assign(_Ip(__x.begin()), _Ip(__x.end()));
1027    }
1028}
1029
1030template <class _Tp, class _Alloc>
1031inline
1032forward_list<_Tp, _Alloc>&
1033forward_list<_Tp, _Alloc>::operator=(forward_list&& __x)
1034    _NOEXCEPT_(
1035             __node_traits::propagate_on_container_move_assignment::value &&
1036             is_nothrow_move_assignable<allocator_type>::value)
1037{
1038    __move_assign(__x, integral_constant<bool,
1039          __node_traits::propagate_on_container_move_assignment::value>());
1040    return *this;
1041}
1042
1043#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1044
1045#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1046
1047template <class _Tp, class _Alloc>
1048inline
1049forward_list<_Tp, _Alloc>&
1050forward_list<_Tp, _Alloc>::operator=(initializer_list<value_type> __il)
1051{
1052    assign(__il.begin(), __il.end());
1053    return *this;
1054}
1055
1056#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1057
1058template <class _Tp, class _Alloc>
1059template <class _InputIterator>
1060typename enable_if
1061<
1062    __is_input_iterator<_InputIterator>::value,
1063    void
1064>::type
1065forward_list<_Tp, _Alloc>::assign(_InputIterator __f, _InputIterator __l)
1066{
1067    iterator __i = before_begin();
1068    iterator __j = _VSTD::next(__i);
1069    iterator __e = end();
1070    for (; __j != __e && __f != __l; ++__i, (void) ++__j, ++__f)
1071        *__j = *__f;
1072    if (__j == __e)
1073        insert_after(__i, __f, __l);
1074    else
1075        erase_after(__i, __e);
1076}
1077
1078template <class _Tp, class _Alloc>
1079void
1080forward_list<_Tp, _Alloc>::assign(size_type __n, const value_type& __v)
1081{
1082    iterator __i = before_begin();
1083    iterator __j = _VSTD::next(__i);
1084    iterator __e = end();
1085    for (; __j != __e && __n > 0; --__n, ++__i, ++__j)
1086        *__j = __v;
1087    if (__j == __e)
1088        insert_after(__i, __n, __v);
1089    else
1090        erase_after(__i, __e);
1091}
1092
1093#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1094
1095template <class _Tp, class _Alloc>
1096inline
1097void
1098forward_list<_Tp, _Alloc>::assign(initializer_list<value_type> __il)
1099{
1100    assign(__il.begin(), __il.end());
1101}
1102
1103#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1104
1105#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1106#ifndef _LIBCPP_HAS_NO_VARIADICS
1107
1108template <class _Tp, class _Alloc>
1109template <class... _Args>
1110#if _LIBCPP_STD_VER > 14
1111typename forward_list<_Tp, _Alloc>::reference
1112#else
1113void
1114#endif
1115forward_list<_Tp, _Alloc>::emplace_front(_Args&&... __args)
1116{
1117    __node_allocator& __a = base::__alloc();
1118    typedef __allocator_destructor<__node_allocator> _Dp;
1119    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1120    __node_traits::construct(__a, _VSTD::addressof(__h->__value_),
1121                                  _VSTD::forward<_Args>(__args)...);
1122    __h->__next_ = base::__before_begin()->__next_;
1123    base::__before_begin()->__next_ = __h.release();
1124#if _LIBCPP_STD_VER > 14
1125    return base::__before_begin()->__next_->__value_;
1126#endif
1127}
1128
1129#endif  // _LIBCPP_HAS_NO_VARIADICS
1130
1131template <class _Tp, class _Alloc>
1132void
1133forward_list<_Tp, _Alloc>::push_front(value_type&& __v)
1134{
1135    __node_allocator& __a = base::__alloc();
1136    typedef __allocator_destructor<__node_allocator> _Dp;
1137    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1138    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), _VSTD::move(__v));
1139    __h->__next_ = base::__before_begin()->__next_;
1140    base::__before_begin()->__next_ = __h.release();
1141}
1142
1143#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1144
1145template <class _Tp, class _Alloc>
1146void
1147forward_list<_Tp, _Alloc>::push_front(const value_type& __v)
1148{
1149    __node_allocator& __a = base::__alloc();
1150    typedef __allocator_destructor<__node_allocator> _Dp;
1151    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1152    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1153    __h->__next_ = base::__before_begin()->__next_;
1154    base::__before_begin()->__next_ = __h.release();
1155}
1156
1157template <class _Tp, class _Alloc>
1158void
1159forward_list<_Tp, _Alloc>::pop_front()
1160{
1161    __node_allocator& __a = base::__alloc();
1162    __node_pointer __p = base::__before_begin()->__next_;
1163    base::__before_begin()->__next_ = __p->__next_;
1164    __node_traits::destroy(__a, _VSTD::addressof(__p->__value_));
1165    __node_traits::deallocate(__a, __p, 1);
1166}
1167
1168#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1169#ifndef _LIBCPP_HAS_NO_VARIADICS
1170
1171template <class _Tp, class _Alloc>
1172template <class... _Args>
1173typename forward_list<_Tp, _Alloc>::iterator
1174forward_list<_Tp, _Alloc>::emplace_after(const_iterator __p, _Args&&... __args)
1175{
1176    __begin_node_pointer const __r = __p.__get_begin();
1177    __node_allocator& __a = base::__alloc();
1178    typedef __allocator_destructor<__node_allocator> _Dp;
1179    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1180    __node_traits::construct(__a, _VSTD::addressof(__h->__value_),
1181                                  _VSTD::forward<_Args>(__args)...);
1182    __h->__next_ = __r->__next_;
1183    __r->__next_ = __h.release();
1184    return iterator(__r->__next_);
1185}
1186
1187#endif  // _LIBCPP_HAS_NO_VARIADICS
1188
1189template <class _Tp, class _Alloc>
1190typename forward_list<_Tp, _Alloc>::iterator
1191forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, value_type&& __v)
1192{
1193    __begin_node_pointer const __r = __p.__get_begin();
1194    __node_allocator& __a = base::__alloc();
1195    typedef __allocator_destructor<__node_allocator> _Dp;
1196    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1197    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), _VSTD::move(__v));
1198    __h->__next_ = __r->__next_;
1199    __r->__next_ = __h.release();
1200    return iterator(__r->__next_);
1201}
1202
1203#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1204
1205template <class _Tp, class _Alloc>
1206typename forward_list<_Tp, _Alloc>::iterator
1207forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, const value_type& __v)
1208{
1209    __begin_node_pointer const __r = __p.__get_begin();
1210    __node_allocator& __a = base::__alloc();
1211    typedef __allocator_destructor<__node_allocator> _Dp;
1212    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1213    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1214    __h->__next_ = __r->__next_;
1215    __r->__next_ = __h.release();
1216    return iterator(__r->__next_);
1217}
1218
1219template <class _Tp, class _Alloc>
1220typename forward_list<_Tp, _Alloc>::iterator
1221forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, size_type __n,
1222                                        const value_type& __v)
1223{
1224    __begin_node_pointer __r = __p.__get_begin();
1225    if (__n > 0)
1226    {
1227        __node_allocator& __a = base::__alloc();
1228        typedef __allocator_destructor<__node_allocator> _Dp;
1229        unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1230        __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1231        __node_pointer __first = __h.release();
1232        __node_pointer __last = __first;
1233#ifndef _LIBCPP_NO_EXCEPTIONS
1234        try
1235        {
1236#endif  // _LIBCPP_NO_EXCEPTIONS
1237            for (--__n; __n != 0; --__n, __last = __last->__next_)
1238            {
1239                __h.reset(__node_traits::allocate(__a, 1));
1240                __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1241                __last->__next_ = __h.release();
1242            }
1243#ifndef _LIBCPP_NO_EXCEPTIONS
1244        }
1245        catch (...)
1246        {
1247            while (__first != nullptr)
1248            {
1249                __node_pointer __next = __first->__next_;
1250                __node_traits::destroy(__a, _VSTD::addressof(__first->__value_));
1251                __node_traits::deallocate(__a, __first, 1);
1252                __first = __next;
1253            }
1254            throw;
1255        }
1256#endif  // _LIBCPP_NO_EXCEPTIONS
1257        __last->__next_ = __r->__next_;
1258        __r->__next_ = __first;
1259        __r = static_cast<__begin_node_pointer>(__last);
1260    }
1261    return iterator(__r);
1262}
1263
1264template <class _Tp, class _Alloc>
1265template <class _InputIterator>
1266typename enable_if
1267<
1268    __is_input_iterator<_InputIterator>::value,
1269    typename forward_list<_Tp, _Alloc>::iterator
1270>::type
1271forward_list<_Tp, _Alloc>::insert_after(const_iterator __p,
1272                                        _InputIterator __f, _InputIterator __l)
1273{
1274    __begin_node_pointer __r = __p.__get_begin();
1275    if (__f != __l)
1276    {
1277        __node_allocator& __a = base::__alloc();
1278        typedef __allocator_destructor<__node_allocator> _Dp;
1279        unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1280        __node_traits::construct(__a, _VSTD::addressof(__h->__value_), *__f);
1281        __node_pointer __first = __h.release();
1282        __node_pointer __last = __first;
1283#ifndef _LIBCPP_NO_EXCEPTIONS
1284        try
1285        {
1286#endif  // _LIBCPP_NO_EXCEPTIONS
1287            for (++__f; __f != __l; ++__f, ((void)(__last = __last->__next_)))
1288            {
1289                __h.reset(__node_traits::allocate(__a, 1));
1290                __node_traits::construct(__a, _VSTD::addressof(__h->__value_), *__f);
1291                __last->__next_ = __h.release();
1292            }
1293#ifndef _LIBCPP_NO_EXCEPTIONS
1294        }
1295        catch (...)
1296        {
1297            while (__first != nullptr)
1298            {
1299                __node_pointer __next = __first->__next_;
1300                __node_traits::destroy(__a, _VSTD::addressof(__first->__value_));
1301                __node_traits::deallocate(__a, __first, 1);
1302                __first = __next;
1303            }
1304            throw;
1305        }
1306#endif  // _LIBCPP_NO_EXCEPTIONS
1307        __last->__next_ = __r->__next_;
1308        __r->__next_ = __first;
1309        __r = static_cast<__begin_node_pointer>(__last);
1310    }
1311    return iterator(__r);
1312}
1313
1314template <class _Tp, class _Alloc>
1315typename forward_list<_Tp, _Alloc>::iterator
1316forward_list<_Tp, _Alloc>::erase_after(const_iterator __f)
1317{
1318    __begin_node_pointer __p = __f.__get_begin();
1319    __node_pointer __n = __p->__next_;
1320    __p->__next_ = __n->__next_;
1321    __node_allocator& __a = base::__alloc();
1322    __node_traits::destroy(__a, _VSTD::addressof(__n->__value_));
1323    __node_traits::deallocate(__a, __n, 1);
1324    return iterator(__p->__next_);
1325}
1326
1327template <class _Tp, class _Alloc>
1328typename forward_list<_Tp, _Alloc>::iterator
1329forward_list<_Tp, _Alloc>::erase_after(const_iterator __f, const_iterator __l)
1330{
1331    __node_pointer __e = __l.__get_unsafe_node_pointer();
1332    if (__f != __l)
1333    {
1334        __begin_node_pointer __bp = __f.__get_begin();
1335
1336        __node_pointer __n = __bp->__next_;
1337        if (__n != __e)
1338        {
1339            __bp->__next_ = __e;
1340            __node_allocator& __a = base::__alloc();
1341            do
1342            {
1343                __node_pointer __tmp = __n->__next_;
1344                __node_traits::destroy(__a, _VSTD::addressof(__n->__value_));
1345                __node_traits::deallocate(__a, __n, 1);
1346                __n = __tmp;
1347            } while (__n != __e);
1348        }
1349    }
1350    return iterator(__e);
1351}
1352
1353template <class _Tp, class _Alloc>
1354void
1355forward_list<_Tp, _Alloc>::resize(size_type __n)
1356{
1357    size_type __sz = 0;
1358    iterator __p = before_begin();
1359    iterator __i = begin();
1360    iterator __e = end();
1361    for (; __i != __e && __sz < __n; ++__p, ++__i, ++__sz)
1362        ;
1363    if (__i != __e)
1364        erase_after(__p, __e);
1365    else
1366    {
1367        __n -= __sz;
1368        if (__n > 0)
1369        {
1370            __node_allocator& __a = base::__alloc();
1371            typedef __allocator_destructor<__node_allocator> _Dp;
1372            unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
1373            for (__begin_node_pointer __ptr = __p.__get_begin(); __n > 0; --__n,
1374                                                         __ptr = __ptr->__next_as_begin())
1375            {
1376                __h.reset(__node_traits::allocate(__a, 1));
1377                __node_traits::construct(__a, _VSTD::addressof(__h->__value_));
1378                __h->__next_ = nullptr;
1379                __ptr->__next_ = __h.release();
1380            }
1381        }
1382    }
1383}
1384
1385template <class _Tp, class _Alloc>
1386void
1387forward_list<_Tp, _Alloc>::resize(size_type __n, const value_type& __v)
1388{
1389    size_type __sz = 0;
1390    iterator __p = before_begin();
1391    iterator __i = begin();
1392    iterator __e = end();
1393    for (; __i != __e && __sz < __n; ++__p, ++__i, ++__sz)
1394        ;
1395    if (__i != __e)
1396        erase_after(__p, __e);
1397    else
1398    {
1399        __n -= __sz;
1400        if (__n > 0)
1401        {
1402            __node_allocator& __a = base::__alloc();
1403            typedef __allocator_destructor<__node_allocator> _Dp;
1404            unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
1405            for (__begin_node_pointer __ptr = __p.__get_begin(); __n > 0; --__n,
1406                                                         __ptr = __ptr->__next_as_begin())
1407            {
1408                __h.reset(__node_traits::allocate(__a, 1));
1409                __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1410                __h->__next_ = nullptr;
1411                __ptr->__next_ = __h.release();
1412            }
1413        }
1414    }
1415}
1416
1417template <class _Tp, class _Alloc>
1418void
1419forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1420                                        forward_list& __x)
1421{
1422    if (!__x.empty())
1423    {
1424        if (__p.__get_begin()->__next_ != nullptr)
1425        {
1426            const_iterator __lm1 = __x.before_begin();
1427            while (__lm1.__get_begin()->__next_ != nullptr)
1428                ++__lm1;
1429            __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
1430        }
1431        __p.__get_begin()->__next_ = __x.__before_begin()->__next_;
1432        __x.__before_begin()->__next_ = nullptr;
1433    }
1434}
1435
1436template <class _Tp, class _Alloc>
1437void
1438forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1439                                        forward_list& /*__other*/,
1440                                        const_iterator __i)
1441{
1442    const_iterator __lm1 = _VSTD::next(__i);
1443    if (__p != __i && __p != __lm1)
1444    {
1445        __i.__get_begin()->__next_ = __lm1.__get_begin()->__next_;
1446        __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
1447        __p.__get_begin()->__next_ = __lm1.__get_unsafe_node_pointer();
1448    }
1449}
1450
1451template <class _Tp, class _Alloc>
1452void
1453forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1454                                        forward_list& /*__other*/,
1455                                        const_iterator __f, const_iterator __l)
1456{
1457    if (__f != __l && __p != __f)
1458    {
1459        const_iterator __lm1 = __f;
1460        while (__lm1.__get_begin()->__next_ != __l.__get_begin())
1461            ++__lm1;
1462        if (__f != __lm1)
1463        {
1464            __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
1465            __p.__get_begin()->__next_ = __f.__get_begin()->__next_;
1466            __f.__get_begin()->__next_ = __l.__get_unsafe_node_pointer();
1467        }
1468    }
1469}
1470
1471#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1472
1473template <class _Tp, class _Alloc>
1474inline _LIBCPP_INLINE_VISIBILITY
1475void
1476forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1477                                        forward_list&& __x)
1478{
1479    splice_after(__p, __x);
1480}
1481
1482template <class _Tp, class _Alloc>
1483inline _LIBCPP_INLINE_VISIBILITY
1484void
1485forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1486                                        forward_list&& __x,
1487                                        const_iterator __i)
1488{
1489    splice_after(__p, __x, __i);
1490}
1491
1492template <class _Tp, class _Alloc>
1493inline _LIBCPP_INLINE_VISIBILITY
1494void
1495forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1496                                        forward_list&& __x,
1497                                        const_iterator __f, const_iterator __l)
1498{
1499    splice_after(__p, __x, __f, __l);
1500}
1501
1502#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1503
1504template <class _Tp, class _Alloc>
1505void
1506forward_list<_Tp, _Alloc>::remove(const value_type& __v)
1507{
1508    forward_list<_Tp, _Alloc> __deleted_nodes; // collect the nodes we're removing
1509    iterator __e = end();
1510    for (iterator __i = before_begin(); __i.__get_begin()->__next_ != nullptr;)
1511    {
1512        if (__i.__get_begin()->__next_->__value_ == __v)
1513        {
1514            iterator __j = _VSTD::next(__i, 2);
1515            for (; __j != __e && *__j == __v; ++__j)
1516                ;
1517            __deleted_nodes.splice_after(__deleted_nodes.before_begin(), *this, __i, __j);
1518            if (__j == __e)
1519                break;
1520            __i = __j;
1521        }
1522        else
1523            ++__i;
1524    }
1525}
1526
1527template <class _Tp, class _Alloc>
1528template <class _Predicate>
1529void
1530forward_list<_Tp, _Alloc>::remove_if(_Predicate __pred)
1531{
1532    iterator __e = end();
1533    for (iterator __i = before_begin(); __i.__get_begin()->__next_ != nullptr;)
1534    {
1535        if (__pred(__i.__get_begin()->__next_->__value_))
1536        {
1537            iterator __j = _VSTD::next(__i, 2);
1538            for (; __j != __e && __pred(*__j); ++__j)
1539                ;
1540            erase_after(__i, __j);
1541            if (__j == __e)
1542                break;
1543            __i = __j;
1544        }
1545        else
1546            ++__i;
1547    }
1548}
1549
1550template <class _Tp, class _Alloc>
1551template <class _BinaryPredicate>
1552void
1553forward_list<_Tp, _Alloc>::unique(_BinaryPredicate __binary_pred)
1554{
1555    for (iterator __i = begin(), __e = end(); __i != __e;)
1556    {
1557        iterator __j = _VSTD::next(__i);
1558        for (; __j != __e && __binary_pred(*__i, *__j); ++__j)
1559            ;
1560        if (__i.__get_begin()->__next_ != __j.__get_unsafe_node_pointer())
1561            erase_after(__i, __j);
1562        __i = __j;
1563    }
1564}
1565
1566template <class _Tp, class _Alloc>
1567template <class _Compare>
1568void
1569forward_list<_Tp, _Alloc>::merge(forward_list& __x, _Compare __comp)
1570{
1571    if (this != &__x)
1572    {
1573        base::__before_begin()->__next_ = __merge(base::__before_begin()->__next_,
1574                                                    __x.__before_begin()->__next_,
1575                                                    __comp);
1576        __x.__before_begin()->__next_ = nullptr;
1577    }
1578}
1579
1580template <class _Tp, class _Alloc>
1581template <class _Compare>
1582typename forward_list<_Tp, _Alloc>::__node_pointer
1583forward_list<_Tp, _Alloc>::__merge(__node_pointer __f1, __node_pointer __f2,
1584                                   _Compare& __comp)
1585{
1586    if (__f1 == nullptr)
1587        return __f2;
1588    if (__f2 == nullptr)
1589        return __f1;
1590    __node_pointer __r;
1591    if (__comp(__f2->__value_, __f1->__value_))
1592    {
1593        __node_pointer __t = __f2;
1594        while (__t->__next_ != nullptr &&
1595                             __comp(__t->__next_->__value_, __f1->__value_))
1596            __t = __t->__next_;
1597        __r = __f2;
1598        __f2 = __t->__next_;
1599        __t->__next_ = __f1;
1600    }
1601    else
1602        __r = __f1;
1603    __node_pointer __p = __f1;
1604    __f1 = __f1->__next_;
1605    while (__f1 != nullptr && __f2 != nullptr)
1606    {
1607        if (__comp(__f2->__value_, __f1->__value_))
1608        {
1609            __node_pointer __t = __f2;
1610            while (__t->__next_ != nullptr &&
1611                                 __comp(__t->__next_->__value_, __f1->__value_))
1612                __t = __t->__next_;
1613            __p->__next_ = __f2;
1614            __f2 = __t->__next_;
1615            __t->__next_ = __f1;
1616        }
1617        __p = __f1;
1618        __f1 = __f1->__next_;
1619    }
1620    if (__f2 != nullptr)
1621        __p->__next_ = __f2;
1622    return __r;
1623}
1624
1625template <class _Tp, class _Alloc>
1626template <class _Compare>
1627inline
1628void
1629forward_list<_Tp, _Alloc>::sort(_Compare __comp)
1630{
1631    base::__before_begin()->__next_ = __sort(base::__before_begin()->__next_,
1632                                       _VSTD::distance(begin(), end()), __comp);
1633}
1634
1635template <class _Tp, class _Alloc>
1636template <class _Compare>
1637typename forward_list<_Tp, _Alloc>::__node_pointer
1638forward_list<_Tp, _Alloc>::__sort(__node_pointer __f1, difference_type __sz,
1639                                  _Compare& __comp)
1640{
1641    switch (__sz)
1642    {
1643    case 0:
1644    case 1:
1645        return __f1;
1646    case 2:
1647        if (__comp(__f1->__next_->__value_, __f1->__value_))
1648        {
1649            __node_pointer __t = __f1->__next_;
1650            __t->__next_ = __f1;
1651            __f1->__next_ = nullptr;
1652            __f1 = __t;
1653        }
1654        return __f1;
1655    }
1656    difference_type __sz1 = __sz / 2;
1657    difference_type __sz2 = __sz - __sz1;
1658    __node_pointer __t = _VSTD::next(iterator(__f1), __sz1 - 1).__get_unsafe_node_pointer();
1659    __node_pointer __f2 = __t->__next_;
1660    __t->__next_ = nullptr;
1661    return __merge(__sort(__f1, __sz1, __comp),
1662                   __sort(__f2, __sz2, __comp), __comp);
1663}
1664
1665template <class _Tp, class _Alloc>
1666void
1667forward_list<_Tp, _Alloc>::reverse() _NOEXCEPT
1668{
1669    __node_pointer __p = base::__before_begin()->__next_;
1670    if (__p != nullptr)
1671    {
1672        __node_pointer __f = __p->__next_;
1673        __p->__next_ = nullptr;
1674        while (__f != nullptr)
1675        {
1676            __node_pointer __t = __f->__next_;
1677            __f->__next_ = __p;
1678            __p = __f;
1679            __f = __t;
1680        }
1681        base::__before_begin()->__next_ = __p;
1682    }
1683}
1684
1685template <class _Tp, class _Alloc>
1686bool operator==(const forward_list<_Tp, _Alloc>& __x,
1687                const forward_list<_Tp, _Alloc>& __y)
1688{
1689    typedef forward_list<_Tp, _Alloc> _Cp;
1690    typedef typename _Cp::const_iterator _Ip;
1691    _Ip __ix = __x.begin();
1692    _Ip __ex = __x.end();
1693    _Ip __iy = __y.begin();
1694    _Ip __ey = __y.end();
1695    for (; __ix != __ex && __iy != __ey; ++__ix, ++__iy)
1696        if (!(*__ix == *__iy))
1697            return false;
1698    return (__ix == __ex) == (__iy == __ey);
1699}
1700
1701template <class _Tp, class _Alloc>
1702inline _LIBCPP_INLINE_VISIBILITY
1703bool operator!=(const forward_list<_Tp, _Alloc>& __x,
1704                const forward_list<_Tp, _Alloc>& __y)
1705{
1706    return !(__x == __y);
1707}
1708
1709template <class _Tp, class _Alloc>
1710inline _LIBCPP_INLINE_VISIBILITY
1711bool operator< (const forward_list<_Tp, _Alloc>& __x,
1712                const forward_list<_Tp, _Alloc>& __y)
1713{
1714    return _VSTD::lexicographical_compare(__x.begin(), __x.end(),
1715                                         __y.begin(), __y.end());
1716}
1717
1718template <class _Tp, class _Alloc>
1719inline _LIBCPP_INLINE_VISIBILITY
1720bool operator> (const forward_list<_Tp, _Alloc>& __x,
1721                const forward_list<_Tp, _Alloc>& __y)
1722{
1723    return __y < __x;
1724}
1725
1726template <class _Tp, class _Alloc>
1727inline _LIBCPP_INLINE_VISIBILITY
1728bool operator>=(const forward_list<_Tp, _Alloc>& __x,
1729                const forward_list<_Tp, _Alloc>& __y)
1730{
1731    return !(__x < __y);
1732}
1733
1734template <class _Tp, class _Alloc>
1735inline _LIBCPP_INLINE_VISIBILITY
1736bool operator<=(const forward_list<_Tp, _Alloc>& __x,
1737                const forward_list<_Tp, _Alloc>& __y)
1738{
1739    return !(__y < __x);
1740}
1741
1742template <class _Tp, class _Alloc>
1743inline _LIBCPP_INLINE_VISIBILITY
1744void
1745swap(forward_list<_Tp, _Alloc>& __x, forward_list<_Tp, _Alloc>& __y)
1746    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1747{
1748    __x.swap(__y);
1749}
1750
1751_LIBCPP_END_NAMESPACE_STD
1752
1753#endif  // _LIBCPP_FORWARD_LIST
1754