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_CXX03_LANG
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_CXX03_LANG
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_CXX03_LANG
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_CXX03_LANG
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
660    forward_list& operator=(const forward_list& __x);
661
662#ifndef _LIBCPP_CXX03_LANG
663    _LIBCPP_INLINE_VISIBILITY
664    forward_list(forward_list&& __x)
665        _NOEXCEPT_(is_nothrow_move_constructible<base>::value)
666        : base(_VSTD::move(__x)) {}
667    forward_list(forward_list&& __x, const allocator_type& __a);
668
669    forward_list(initializer_list<value_type> __il);
670    forward_list(initializer_list<value_type> __il, const allocator_type& __a);
671
672    _LIBCPP_INLINE_VISIBILITY
673    forward_list& operator=(forward_list&& __x)
674        _NOEXCEPT_(
675             __node_traits::propagate_on_container_move_assignment::value &&
676             is_nothrow_move_assignable<allocator_type>::value);
677
678    _LIBCPP_INLINE_VISIBILITY
679    forward_list& operator=(initializer_list<value_type> __il);
680
681    _LIBCPP_INLINE_VISIBILITY
682    void assign(initializer_list<value_type> __il);
683#endif  // _LIBCPP_CXX03_LANG
684
685    // ~forward_list() = default;
686
687    template <class _InputIterator>
688        typename enable_if
689        <
690            __is_input_iterator<_InputIterator>::value,
691            void
692        >::type
693        assign(_InputIterator __f, _InputIterator __l);
694    void assign(size_type __n, const value_type& __v);
695
696    _LIBCPP_INLINE_VISIBILITY
697    allocator_type get_allocator() const _NOEXCEPT
698        {return allocator_type(base::__alloc());}
699
700    _LIBCPP_INLINE_VISIBILITY
701    iterator       begin() _NOEXCEPT
702        {return       iterator(base::__before_begin()->__next_);}
703    _LIBCPP_INLINE_VISIBILITY
704    const_iterator begin() const _NOEXCEPT
705        {return const_iterator(base::__before_begin()->__next_);}
706    _LIBCPP_INLINE_VISIBILITY
707    iterator       end() _NOEXCEPT
708        {return       iterator(nullptr);}
709    _LIBCPP_INLINE_VISIBILITY
710    const_iterator end() const _NOEXCEPT
711        {return const_iterator(nullptr);}
712
713    _LIBCPP_INLINE_VISIBILITY
714    const_iterator cbegin() const _NOEXCEPT
715        {return const_iterator(base::__before_begin()->__next_);}
716    _LIBCPP_INLINE_VISIBILITY
717    const_iterator cend() const _NOEXCEPT
718        {return const_iterator(nullptr);}
719
720    _LIBCPP_INLINE_VISIBILITY
721    iterator       before_begin() _NOEXCEPT
722        {return       iterator(base::__before_begin());}
723    _LIBCPP_INLINE_VISIBILITY
724    const_iterator before_begin() const _NOEXCEPT
725        {return const_iterator(base::__before_begin());}
726    _LIBCPP_INLINE_VISIBILITY
727    const_iterator cbefore_begin() const _NOEXCEPT
728        {return const_iterator(base::__before_begin());}
729
730    _LIBCPP_INLINE_VISIBILITY
731    bool empty() const _NOEXCEPT
732        {return base::__before_begin()->__next_ == nullptr;}
733    _LIBCPP_INLINE_VISIBILITY
734    size_type max_size() const _NOEXCEPT {
735        return std::min<size_type>(
736            __node_traits::max_size(base::__alloc()),
737            numeric_limits<difference_type>::max());
738    }
739
740    _LIBCPP_INLINE_VISIBILITY
741    reference       front()       {return base::__before_begin()->__next_->__value_;}
742    _LIBCPP_INLINE_VISIBILITY
743    const_reference front() const {return base::__before_begin()->__next_->__value_;}
744
745#ifndef _LIBCPP_CXX03_LANG
746#if _LIBCPP_STD_VER > 14
747    template <class... _Args> reference emplace_front(_Args&&... __args);
748#else
749    template <class... _Args> void      emplace_front(_Args&&... __args);
750#endif
751    void push_front(value_type&& __v);
752#endif  // _LIBCPP_CXX03_LANG
753    void push_front(const value_type& __v);
754
755    void pop_front();
756
757#ifndef _LIBCPP_CXX03_LANG
758    template <class... _Args>
759        iterator emplace_after(const_iterator __p, _Args&&... __args);
760
761    iterator insert_after(const_iterator __p, value_type&& __v);
762    iterator insert_after(const_iterator __p, initializer_list<value_type> __il)
763        {return insert_after(__p, __il.begin(), __il.end());}
764#endif  // _LIBCPP_CXX03_LANG
765    iterator insert_after(const_iterator __p, const value_type& __v);
766    iterator insert_after(const_iterator __p, size_type __n, const value_type& __v);
767    template <class _InputIterator>
768        _LIBCPP_INLINE_VISIBILITY
769        typename enable_if
770        <
771            __is_input_iterator<_InputIterator>::value,
772            iterator
773        >::type
774        insert_after(const_iterator __p, _InputIterator __f, _InputIterator __l);
775
776    iterator erase_after(const_iterator __p);
777    iterator erase_after(const_iterator __f, const_iterator __l);
778
779    _LIBCPP_INLINE_VISIBILITY
780    void swap(forward_list& __x)
781#if _LIBCPP_STD_VER >= 14
782        _NOEXCEPT
783#else
784        _NOEXCEPT_(!__node_traits::propagate_on_container_swap::value ||
785                   __is_nothrow_swappable<__node_allocator>::value)
786#endif
787        {base::swap(__x);}
788
789    void resize(size_type __n);
790    void resize(size_type __n, const value_type& __v);
791    _LIBCPP_INLINE_VISIBILITY
792    void clear() _NOEXCEPT {base::clear();}
793
794#ifndef _LIBCPP_CXX03_LANG
795    _LIBCPP_INLINE_VISIBILITY
796    void splice_after(const_iterator __p, forward_list&& __x);
797    _LIBCPP_INLINE_VISIBILITY
798    void splice_after(const_iterator __p, forward_list&& __x, const_iterator __i);
799    _LIBCPP_INLINE_VISIBILITY
800    void splice_after(const_iterator __p, forward_list&& __x,
801                      const_iterator __f, const_iterator __l);
802#endif  // _LIBCPP_CXX03_LANG
803    void splice_after(const_iterator __p, forward_list& __x);
804    void splice_after(const_iterator __p, forward_list& __x, const_iterator __i);
805    void splice_after(const_iterator __p, forward_list& __x,
806                      const_iterator __f, const_iterator __l);
807    void remove(const value_type& __v);
808    template <class _Predicate> void remove_if(_Predicate __pred);
809    _LIBCPP_INLINE_VISIBILITY
810    void unique() {unique(__equal_to<value_type>());}
811    template <class _BinaryPredicate> void unique(_BinaryPredicate __binary_pred);
812#ifndef _LIBCPP_CXX03_LANG
813    _LIBCPP_INLINE_VISIBILITY
814    void merge(forward_list&& __x) {merge(__x, __less<value_type>());}
815    template <class _Compare>
816        _LIBCPP_INLINE_VISIBILITY
817        void merge(forward_list&& __x, _Compare __comp)
818        {merge(__x, _VSTD::move(__comp));}
819#endif  // _LIBCPP_CXX03_LANG
820    _LIBCPP_INLINE_VISIBILITY
821    void merge(forward_list& __x) {merge(__x, __less<value_type>());}
822    template <class _Compare> void merge(forward_list& __x, _Compare __comp);
823    _LIBCPP_INLINE_VISIBILITY
824    void sort() {sort(__less<value_type>());}
825    template <class _Compare> _LIBCPP_INLINE_VISIBILITY void sort(_Compare __comp);
826    void reverse() _NOEXCEPT;
827
828private:
829
830#ifndef _LIBCPP_CXX03_LANG
831    void __move_assign(forward_list& __x, true_type)
832        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
833    void __move_assign(forward_list& __x, false_type);
834#endif  // _LIBCPP_CXX03_LANG
835
836    template <class _Compare>
837        static
838        __node_pointer
839        __merge(__node_pointer __f1, __node_pointer __f2, _Compare& __comp);
840
841    template <class _Compare>
842        static
843        __node_pointer
844        __sort(__node_pointer __f, difference_type __sz, _Compare& __comp);
845};
846
847template <class _Tp, class _Alloc>
848inline
849forward_list<_Tp, _Alloc>::forward_list(const allocator_type& __a)
850    : base(__a)
851{
852}
853
854template <class _Tp, class _Alloc>
855forward_list<_Tp, _Alloc>::forward_list(size_type __n)
856{
857    if (__n > 0)
858    {
859        __node_allocator& __a = base::__alloc();
860        typedef __allocator_destructor<__node_allocator> _Dp;
861        unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
862        for (__begin_node_pointer __p = base::__before_begin(); __n > 0; --__n,
863                                                             __p = __p->__next_as_begin())
864        {
865            __h.reset(__node_traits::allocate(__a, 1));
866            __node_traits::construct(__a, _VSTD::addressof(__h->__value_));
867            __h->__next_ = nullptr;
868            __p->__next_ = __h.release();
869        }
870    }
871}
872
873#if _LIBCPP_STD_VER > 11
874template <class _Tp, class _Alloc>
875forward_list<_Tp, _Alloc>::forward_list(size_type __n,
876                                        const allocator_type& __base_alloc)
877    : base ( __base_alloc )
878{
879    if (__n > 0)
880    {
881        __node_allocator& __a = base::__alloc();
882        typedef __allocator_destructor<__node_allocator> _Dp;
883        unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
884        for (__begin_node_pointer __p = base::__before_begin(); __n > 0; --__n,
885                                                             __p = __p->__next_as_begin())
886        {
887            __h.reset(__node_traits::allocate(__a, 1));
888            __node_traits::construct(__a, _VSTD::addressof(__h->__value_));
889            __h->__next_ = nullptr;
890            __p->__next_ = __h.release();
891        }
892    }
893}
894#endif
895
896template <class _Tp, class _Alloc>
897forward_list<_Tp, _Alloc>::forward_list(size_type __n, const value_type& __v)
898{
899    insert_after(cbefore_begin(), __n, __v);
900}
901
902template <class _Tp, class _Alloc>
903forward_list<_Tp, _Alloc>::forward_list(size_type __n, const value_type& __v,
904                                        const allocator_type& __a)
905    : base(__a)
906{
907    insert_after(cbefore_begin(), __n, __v);
908}
909
910template <class _Tp, class _Alloc>
911template <class _InputIterator>
912forward_list<_Tp, _Alloc>::forward_list(_InputIterator __f, _InputIterator __l,
913                                        typename enable_if<
914                                          __is_input_iterator<_InputIterator>::value
915                                        >::type*)
916{
917    insert_after(cbefore_begin(), __f, __l);
918}
919
920template <class _Tp, class _Alloc>
921template <class _InputIterator>
922forward_list<_Tp, _Alloc>::forward_list(_InputIterator __f, _InputIterator __l,
923                                        const allocator_type& __a,
924                                        typename enable_if<
925                                          __is_input_iterator<_InputIterator>::value
926                                        >::type*)
927    : base(__a)
928{
929    insert_after(cbefore_begin(), __f, __l);
930}
931
932template <class _Tp, class _Alloc>
933forward_list<_Tp, _Alloc>::forward_list(const forward_list& __x)
934    : base(allocator_type(
935             __node_traits::select_on_container_copy_construction(__x.__alloc())
936                         )
937          )
938{
939    insert_after(cbefore_begin(), __x.begin(), __x.end());
940}
941
942template <class _Tp, class _Alloc>
943forward_list<_Tp, _Alloc>::forward_list(const forward_list& __x,
944                                        const allocator_type& __a)
945    : base(__a)
946{
947    insert_after(cbefore_begin(), __x.begin(), __x.end());
948}
949
950template <class _Tp, class _Alloc>
951forward_list<_Tp, _Alloc>&
952forward_list<_Tp, _Alloc>::operator=(const forward_list& __x)
953{
954    if (this != &__x)
955    {
956        base::__copy_assign_alloc(__x);
957        assign(__x.begin(), __x.end());
958    }
959    return *this;
960}
961
962#ifndef _LIBCPP_CXX03_LANG
963template <class _Tp, class _Alloc>
964forward_list<_Tp, _Alloc>::forward_list(forward_list&& __x,
965                                        const allocator_type& __a)
966    : base(_VSTD::move(__x), __a)
967{
968    if (base::__alloc() != __x.__alloc())
969    {
970        typedef move_iterator<iterator> _Ip;
971        insert_after(cbefore_begin(), _Ip(__x.begin()), _Ip(__x.end()));
972    }
973}
974
975template <class _Tp, class _Alloc>
976forward_list<_Tp, _Alloc>::forward_list(initializer_list<value_type> __il)
977{
978    insert_after(cbefore_begin(), __il.begin(), __il.end());
979}
980
981template <class _Tp, class _Alloc>
982forward_list<_Tp, _Alloc>::forward_list(initializer_list<value_type> __il,
983                                        const allocator_type& __a)
984    : base(__a)
985{
986    insert_after(cbefore_begin(), __il.begin(), __il.end());
987}
988
989template <class _Tp, class _Alloc>
990void
991forward_list<_Tp, _Alloc>::__move_assign(forward_list& __x, true_type)
992    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
993{
994    clear();
995    base::__move_assign_alloc(__x);
996    base::__before_begin()->__next_ = __x.__before_begin()->__next_;
997    __x.__before_begin()->__next_ = nullptr;
998}
999
1000template <class _Tp, class _Alloc>
1001void
1002forward_list<_Tp, _Alloc>::__move_assign(forward_list& __x, false_type)
1003{
1004    if (base::__alloc() == __x.__alloc())
1005        __move_assign(__x, true_type());
1006    else
1007    {
1008        typedef move_iterator<iterator> _Ip;
1009        assign(_Ip(__x.begin()), _Ip(__x.end()));
1010    }
1011}
1012
1013template <class _Tp, class _Alloc>
1014inline
1015forward_list<_Tp, _Alloc>&
1016forward_list<_Tp, _Alloc>::operator=(forward_list&& __x)
1017    _NOEXCEPT_(
1018             __node_traits::propagate_on_container_move_assignment::value &&
1019             is_nothrow_move_assignable<allocator_type>::value)
1020{
1021    __move_assign(__x, integral_constant<bool,
1022          __node_traits::propagate_on_container_move_assignment::value>());
1023    return *this;
1024}
1025
1026template <class _Tp, class _Alloc>
1027inline
1028forward_list<_Tp, _Alloc>&
1029forward_list<_Tp, _Alloc>::operator=(initializer_list<value_type> __il)
1030{
1031    assign(__il.begin(), __il.end());
1032    return *this;
1033}
1034
1035#endif  // _LIBCPP_CXX03_LANG
1036
1037template <class _Tp, class _Alloc>
1038template <class _InputIterator>
1039typename enable_if
1040<
1041    __is_input_iterator<_InputIterator>::value,
1042    void
1043>::type
1044forward_list<_Tp, _Alloc>::assign(_InputIterator __f, _InputIterator __l)
1045{
1046    iterator __i = before_begin();
1047    iterator __j = _VSTD::next(__i);
1048    iterator __e = end();
1049    for (; __j != __e && __f != __l; ++__i, (void) ++__j, ++__f)
1050        *__j = *__f;
1051    if (__j == __e)
1052        insert_after(__i, __f, __l);
1053    else
1054        erase_after(__i, __e);
1055}
1056
1057template <class _Tp, class _Alloc>
1058void
1059forward_list<_Tp, _Alloc>::assign(size_type __n, const value_type& __v)
1060{
1061    iterator __i = before_begin();
1062    iterator __j = _VSTD::next(__i);
1063    iterator __e = end();
1064    for (; __j != __e && __n > 0; --__n, ++__i, ++__j)
1065        *__j = __v;
1066    if (__j == __e)
1067        insert_after(__i, __n, __v);
1068    else
1069        erase_after(__i, __e);
1070}
1071
1072#ifndef _LIBCPP_CXX03_LANG
1073
1074template <class _Tp, class _Alloc>
1075inline
1076void
1077forward_list<_Tp, _Alloc>::assign(initializer_list<value_type> __il)
1078{
1079    assign(__il.begin(), __il.end());
1080}
1081
1082template <class _Tp, class _Alloc>
1083template <class... _Args>
1084#if _LIBCPP_STD_VER > 14
1085typename forward_list<_Tp, _Alloc>::reference
1086#else
1087void
1088#endif
1089forward_list<_Tp, _Alloc>::emplace_front(_Args&&... __args)
1090{
1091    __node_allocator& __a = base::__alloc();
1092    typedef __allocator_destructor<__node_allocator> _Dp;
1093    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1094    __node_traits::construct(__a, _VSTD::addressof(__h->__value_),
1095                                  _VSTD::forward<_Args>(__args)...);
1096    __h->__next_ = base::__before_begin()->__next_;
1097    base::__before_begin()->__next_ = __h.release();
1098#if _LIBCPP_STD_VER > 14
1099    return base::__before_begin()->__next_->__value_;
1100#endif
1101}
1102
1103template <class _Tp, class _Alloc>
1104void
1105forward_list<_Tp, _Alloc>::push_front(value_type&& __v)
1106{
1107    __node_allocator& __a = base::__alloc();
1108    typedef __allocator_destructor<__node_allocator> _Dp;
1109    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1110    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), _VSTD::move(__v));
1111    __h->__next_ = base::__before_begin()->__next_;
1112    base::__before_begin()->__next_ = __h.release();
1113}
1114
1115#endif  // _LIBCPP_CXX03_LANG
1116
1117template <class _Tp, class _Alloc>
1118void
1119forward_list<_Tp, _Alloc>::push_front(const value_type& __v)
1120{
1121    __node_allocator& __a = base::__alloc();
1122    typedef __allocator_destructor<__node_allocator> _Dp;
1123    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1124    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1125    __h->__next_ = base::__before_begin()->__next_;
1126    base::__before_begin()->__next_ = __h.release();
1127}
1128
1129template <class _Tp, class _Alloc>
1130void
1131forward_list<_Tp, _Alloc>::pop_front()
1132{
1133    __node_allocator& __a = base::__alloc();
1134    __node_pointer __p = base::__before_begin()->__next_;
1135    base::__before_begin()->__next_ = __p->__next_;
1136    __node_traits::destroy(__a, _VSTD::addressof(__p->__value_));
1137    __node_traits::deallocate(__a, __p, 1);
1138}
1139
1140#ifndef _LIBCPP_CXX03_LANG
1141
1142template <class _Tp, class _Alloc>
1143template <class... _Args>
1144typename forward_list<_Tp, _Alloc>::iterator
1145forward_list<_Tp, _Alloc>::emplace_after(const_iterator __p, _Args&&... __args)
1146{
1147    __begin_node_pointer const __r = __p.__get_begin();
1148    __node_allocator& __a = base::__alloc();
1149    typedef __allocator_destructor<__node_allocator> _Dp;
1150    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1151    __node_traits::construct(__a, _VSTD::addressof(__h->__value_),
1152                                  _VSTD::forward<_Args>(__args)...);
1153    __h->__next_ = __r->__next_;
1154    __r->__next_ = __h.release();
1155    return iterator(__r->__next_);
1156}
1157
1158template <class _Tp, class _Alloc>
1159typename forward_list<_Tp, _Alloc>::iterator
1160forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, value_type&& __v)
1161{
1162    __begin_node_pointer const __r = __p.__get_begin();
1163    __node_allocator& __a = base::__alloc();
1164    typedef __allocator_destructor<__node_allocator> _Dp;
1165    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1166    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), _VSTD::move(__v));
1167    __h->__next_ = __r->__next_;
1168    __r->__next_ = __h.release();
1169    return iterator(__r->__next_);
1170}
1171
1172#endif  // _LIBCPP_CXX03_LANG
1173
1174template <class _Tp, class _Alloc>
1175typename forward_list<_Tp, _Alloc>::iterator
1176forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, const value_type& __v)
1177{
1178    __begin_node_pointer const __r = __p.__get_begin();
1179    __node_allocator& __a = base::__alloc();
1180    typedef __allocator_destructor<__node_allocator> _Dp;
1181    unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1182    __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1183    __h->__next_ = __r->__next_;
1184    __r->__next_ = __h.release();
1185    return iterator(__r->__next_);
1186}
1187
1188template <class _Tp, class _Alloc>
1189typename forward_list<_Tp, _Alloc>::iterator
1190forward_list<_Tp, _Alloc>::insert_after(const_iterator __p, size_type __n,
1191                                        const value_type& __v)
1192{
1193    __begin_node_pointer __r = __p.__get_begin();
1194    if (__n > 0)
1195    {
1196        __node_allocator& __a = base::__alloc();
1197        typedef __allocator_destructor<__node_allocator> _Dp;
1198        unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1199        __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1200        __node_pointer __first = __h.release();
1201        __node_pointer __last = __first;
1202#ifndef _LIBCPP_NO_EXCEPTIONS
1203        try
1204        {
1205#endif  // _LIBCPP_NO_EXCEPTIONS
1206            for (--__n; __n != 0; --__n, __last = __last->__next_)
1207            {
1208                __h.reset(__node_traits::allocate(__a, 1));
1209                __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1210                __last->__next_ = __h.release();
1211            }
1212#ifndef _LIBCPP_NO_EXCEPTIONS
1213        }
1214        catch (...)
1215        {
1216            while (__first != nullptr)
1217            {
1218                __node_pointer __next = __first->__next_;
1219                __node_traits::destroy(__a, _VSTD::addressof(__first->__value_));
1220                __node_traits::deallocate(__a, __first, 1);
1221                __first = __next;
1222            }
1223            throw;
1224        }
1225#endif  // _LIBCPP_NO_EXCEPTIONS
1226        __last->__next_ = __r->__next_;
1227        __r->__next_ = __first;
1228        __r = static_cast<__begin_node_pointer>(__last);
1229    }
1230    return iterator(__r);
1231}
1232
1233template <class _Tp, class _Alloc>
1234template <class _InputIterator>
1235typename enable_if
1236<
1237    __is_input_iterator<_InputIterator>::value,
1238    typename forward_list<_Tp, _Alloc>::iterator
1239>::type
1240forward_list<_Tp, _Alloc>::insert_after(const_iterator __p,
1241                                        _InputIterator __f, _InputIterator __l)
1242{
1243    __begin_node_pointer __r = __p.__get_begin();
1244    if (__f != __l)
1245    {
1246        __node_allocator& __a = base::__alloc();
1247        typedef __allocator_destructor<__node_allocator> _Dp;
1248        unique_ptr<__node, _Dp> __h(__node_traits::allocate(__a, 1), _Dp(__a, 1));
1249        __node_traits::construct(__a, _VSTD::addressof(__h->__value_), *__f);
1250        __node_pointer __first = __h.release();
1251        __node_pointer __last = __first;
1252#ifndef _LIBCPP_NO_EXCEPTIONS
1253        try
1254        {
1255#endif  // _LIBCPP_NO_EXCEPTIONS
1256            for (++__f; __f != __l; ++__f, ((void)(__last = __last->__next_)))
1257            {
1258                __h.reset(__node_traits::allocate(__a, 1));
1259                __node_traits::construct(__a, _VSTD::addressof(__h->__value_), *__f);
1260                __last->__next_ = __h.release();
1261            }
1262#ifndef _LIBCPP_NO_EXCEPTIONS
1263        }
1264        catch (...)
1265        {
1266            while (__first != nullptr)
1267            {
1268                __node_pointer __next = __first->__next_;
1269                __node_traits::destroy(__a, _VSTD::addressof(__first->__value_));
1270                __node_traits::deallocate(__a, __first, 1);
1271                __first = __next;
1272            }
1273            throw;
1274        }
1275#endif  // _LIBCPP_NO_EXCEPTIONS
1276        __last->__next_ = __r->__next_;
1277        __r->__next_ = __first;
1278        __r = static_cast<__begin_node_pointer>(__last);
1279    }
1280    return iterator(__r);
1281}
1282
1283template <class _Tp, class _Alloc>
1284typename forward_list<_Tp, _Alloc>::iterator
1285forward_list<_Tp, _Alloc>::erase_after(const_iterator __f)
1286{
1287    __begin_node_pointer __p = __f.__get_begin();
1288    __node_pointer __n = __p->__next_;
1289    __p->__next_ = __n->__next_;
1290    __node_allocator& __a = base::__alloc();
1291    __node_traits::destroy(__a, _VSTD::addressof(__n->__value_));
1292    __node_traits::deallocate(__a, __n, 1);
1293    return iterator(__p->__next_);
1294}
1295
1296template <class _Tp, class _Alloc>
1297typename forward_list<_Tp, _Alloc>::iterator
1298forward_list<_Tp, _Alloc>::erase_after(const_iterator __f, const_iterator __l)
1299{
1300    __node_pointer __e = __l.__get_unsafe_node_pointer();
1301    if (__f != __l)
1302    {
1303        __begin_node_pointer __bp = __f.__get_begin();
1304
1305        __node_pointer __n = __bp->__next_;
1306        if (__n != __e)
1307        {
1308            __bp->__next_ = __e;
1309            __node_allocator& __a = base::__alloc();
1310            do
1311            {
1312                __node_pointer __tmp = __n->__next_;
1313                __node_traits::destroy(__a, _VSTD::addressof(__n->__value_));
1314                __node_traits::deallocate(__a, __n, 1);
1315                __n = __tmp;
1316            } while (__n != __e);
1317        }
1318    }
1319    return iterator(__e);
1320}
1321
1322template <class _Tp, class _Alloc>
1323void
1324forward_list<_Tp, _Alloc>::resize(size_type __n)
1325{
1326    size_type __sz = 0;
1327    iterator __p = before_begin();
1328    iterator __i = begin();
1329    iterator __e = end();
1330    for (; __i != __e && __sz < __n; ++__p, ++__i, ++__sz)
1331        ;
1332    if (__i != __e)
1333        erase_after(__p, __e);
1334    else
1335    {
1336        __n -= __sz;
1337        if (__n > 0)
1338        {
1339            __node_allocator& __a = base::__alloc();
1340            typedef __allocator_destructor<__node_allocator> _Dp;
1341            unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
1342            for (__begin_node_pointer __ptr = __p.__get_begin(); __n > 0; --__n,
1343                                                         __ptr = __ptr->__next_as_begin())
1344            {
1345                __h.reset(__node_traits::allocate(__a, 1));
1346                __node_traits::construct(__a, _VSTD::addressof(__h->__value_));
1347                __h->__next_ = nullptr;
1348                __ptr->__next_ = __h.release();
1349            }
1350        }
1351    }
1352}
1353
1354template <class _Tp, class _Alloc>
1355void
1356forward_list<_Tp, _Alloc>::resize(size_type __n, const value_type& __v)
1357{
1358    size_type __sz = 0;
1359    iterator __p = before_begin();
1360    iterator __i = begin();
1361    iterator __e = end();
1362    for (; __i != __e && __sz < __n; ++__p, ++__i, ++__sz)
1363        ;
1364    if (__i != __e)
1365        erase_after(__p, __e);
1366    else
1367    {
1368        __n -= __sz;
1369        if (__n > 0)
1370        {
1371            __node_allocator& __a = base::__alloc();
1372            typedef __allocator_destructor<__node_allocator> _Dp;
1373            unique_ptr<__node, _Dp> __h(nullptr, _Dp(__a, 1));
1374            for (__begin_node_pointer __ptr = __p.__get_begin(); __n > 0; --__n,
1375                                                         __ptr = __ptr->__next_as_begin())
1376            {
1377                __h.reset(__node_traits::allocate(__a, 1));
1378                __node_traits::construct(__a, _VSTD::addressof(__h->__value_), __v);
1379                __h->__next_ = nullptr;
1380                __ptr->__next_ = __h.release();
1381            }
1382        }
1383    }
1384}
1385
1386template <class _Tp, class _Alloc>
1387void
1388forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1389                                        forward_list& __x)
1390{
1391    if (!__x.empty())
1392    {
1393        if (__p.__get_begin()->__next_ != nullptr)
1394        {
1395            const_iterator __lm1 = __x.before_begin();
1396            while (__lm1.__get_begin()->__next_ != nullptr)
1397                ++__lm1;
1398            __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
1399        }
1400        __p.__get_begin()->__next_ = __x.__before_begin()->__next_;
1401        __x.__before_begin()->__next_ = nullptr;
1402    }
1403}
1404
1405template <class _Tp, class _Alloc>
1406void
1407forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1408                                        forward_list& /*__other*/,
1409                                        const_iterator __i)
1410{
1411    const_iterator __lm1 = _VSTD::next(__i);
1412    if (__p != __i && __p != __lm1)
1413    {
1414        __i.__get_begin()->__next_ = __lm1.__get_begin()->__next_;
1415        __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
1416        __p.__get_begin()->__next_ = __lm1.__get_unsafe_node_pointer();
1417    }
1418}
1419
1420template <class _Tp, class _Alloc>
1421void
1422forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1423                                        forward_list& /*__other*/,
1424                                        const_iterator __f, const_iterator __l)
1425{
1426    if (__f != __l && __p != __f)
1427    {
1428        const_iterator __lm1 = __f;
1429        while (__lm1.__get_begin()->__next_ != __l.__get_begin())
1430            ++__lm1;
1431        if (__f != __lm1)
1432        {
1433            __lm1.__get_begin()->__next_ = __p.__get_begin()->__next_;
1434            __p.__get_begin()->__next_ = __f.__get_begin()->__next_;
1435            __f.__get_begin()->__next_ = __l.__get_unsafe_node_pointer();
1436        }
1437    }
1438}
1439
1440#ifndef _LIBCPP_CXX03_LANG
1441
1442template <class _Tp, class _Alloc>
1443inline _LIBCPP_INLINE_VISIBILITY
1444void
1445forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1446                                        forward_list&& __x)
1447{
1448    splice_after(__p, __x);
1449}
1450
1451template <class _Tp, class _Alloc>
1452inline _LIBCPP_INLINE_VISIBILITY
1453void
1454forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1455                                        forward_list&& __x,
1456                                        const_iterator __i)
1457{
1458    splice_after(__p, __x, __i);
1459}
1460
1461template <class _Tp, class _Alloc>
1462inline _LIBCPP_INLINE_VISIBILITY
1463void
1464forward_list<_Tp, _Alloc>::splice_after(const_iterator __p,
1465                                        forward_list&& __x,
1466                                        const_iterator __f, const_iterator __l)
1467{
1468    splice_after(__p, __x, __f, __l);
1469}
1470
1471#endif  // _LIBCPP_CXX03_LANG
1472
1473template <class _Tp, class _Alloc>
1474void
1475forward_list<_Tp, _Alloc>::remove(const value_type& __v)
1476{
1477    forward_list<_Tp, _Alloc> __deleted_nodes; // collect the nodes we're removing
1478    iterator __e = end();
1479    for (iterator __i = before_begin(); __i.__get_begin()->__next_ != nullptr;)
1480    {
1481        if (__i.__get_begin()->__next_->__value_ == __v)
1482        {
1483            iterator __j = _VSTD::next(__i, 2);
1484            for (; __j != __e && *__j == __v; ++__j)
1485                ;
1486            __deleted_nodes.splice_after(__deleted_nodes.before_begin(), *this, __i, __j);
1487            if (__j == __e)
1488                break;
1489            __i = __j;
1490        }
1491        else
1492            ++__i;
1493    }
1494}
1495
1496template <class _Tp, class _Alloc>
1497template <class _Predicate>
1498void
1499forward_list<_Tp, _Alloc>::remove_if(_Predicate __pred)
1500{
1501    iterator __e = end();
1502    for (iterator __i = before_begin(); __i.__get_begin()->__next_ != nullptr;)
1503    {
1504        if (__pred(__i.__get_begin()->__next_->__value_))
1505        {
1506            iterator __j = _VSTD::next(__i, 2);
1507            for (; __j != __e && __pred(*__j); ++__j)
1508                ;
1509            erase_after(__i, __j);
1510            if (__j == __e)
1511                break;
1512            __i = __j;
1513        }
1514        else
1515            ++__i;
1516    }
1517}
1518
1519template <class _Tp, class _Alloc>
1520template <class _BinaryPredicate>
1521void
1522forward_list<_Tp, _Alloc>::unique(_BinaryPredicate __binary_pred)
1523{
1524    for (iterator __i = begin(), __e = end(); __i != __e;)
1525    {
1526        iterator __j = _VSTD::next(__i);
1527        for (; __j != __e && __binary_pred(*__i, *__j); ++__j)
1528            ;
1529        if (__i.__get_begin()->__next_ != __j.__get_unsafe_node_pointer())
1530            erase_after(__i, __j);
1531        __i = __j;
1532    }
1533}
1534
1535template <class _Tp, class _Alloc>
1536template <class _Compare>
1537void
1538forward_list<_Tp, _Alloc>::merge(forward_list& __x, _Compare __comp)
1539{
1540    if (this != &__x)
1541    {
1542        base::__before_begin()->__next_ = __merge(base::__before_begin()->__next_,
1543                                                    __x.__before_begin()->__next_,
1544                                                    __comp);
1545        __x.__before_begin()->__next_ = nullptr;
1546    }
1547}
1548
1549template <class _Tp, class _Alloc>
1550template <class _Compare>
1551typename forward_list<_Tp, _Alloc>::__node_pointer
1552forward_list<_Tp, _Alloc>::__merge(__node_pointer __f1, __node_pointer __f2,
1553                                   _Compare& __comp)
1554{
1555    if (__f1 == nullptr)
1556        return __f2;
1557    if (__f2 == nullptr)
1558        return __f1;
1559    __node_pointer __r;
1560    if (__comp(__f2->__value_, __f1->__value_))
1561    {
1562        __node_pointer __t = __f2;
1563        while (__t->__next_ != nullptr &&
1564                             __comp(__t->__next_->__value_, __f1->__value_))
1565            __t = __t->__next_;
1566        __r = __f2;
1567        __f2 = __t->__next_;
1568        __t->__next_ = __f1;
1569    }
1570    else
1571        __r = __f1;
1572    __node_pointer __p = __f1;
1573    __f1 = __f1->__next_;
1574    while (__f1 != nullptr && __f2 != nullptr)
1575    {
1576        if (__comp(__f2->__value_, __f1->__value_))
1577        {
1578            __node_pointer __t = __f2;
1579            while (__t->__next_ != nullptr &&
1580                                 __comp(__t->__next_->__value_, __f1->__value_))
1581                __t = __t->__next_;
1582            __p->__next_ = __f2;
1583            __f2 = __t->__next_;
1584            __t->__next_ = __f1;
1585        }
1586        __p = __f1;
1587        __f1 = __f1->__next_;
1588    }
1589    if (__f2 != nullptr)
1590        __p->__next_ = __f2;
1591    return __r;
1592}
1593
1594template <class _Tp, class _Alloc>
1595template <class _Compare>
1596inline
1597void
1598forward_list<_Tp, _Alloc>::sort(_Compare __comp)
1599{
1600    base::__before_begin()->__next_ = __sort(base::__before_begin()->__next_,
1601                                       _VSTD::distance(begin(), end()), __comp);
1602}
1603
1604template <class _Tp, class _Alloc>
1605template <class _Compare>
1606typename forward_list<_Tp, _Alloc>::__node_pointer
1607forward_list<_Tp, _Alloc>::__sort(__node_pointer __f1, difference_type __sz,
1608                                  _Compare& __comp)
1609{
1610    switch (__sz)
1611    {
1612    case 0:
1613    case 1:
1614        return __f1;
1615    case 2:
1616        if (__comp(__f1->__next_->__value_, __f1->__value_))
1617        {
1618            __node_pointer __t = __f1->__next_;
1619            __t->__next_ = __f1;
1620            __f1->__next_ = nullptr;
1621            __f1 = __t;
1622        }
1623        return __f1;
1624    }
1625    difference_type __sz1 = __sz / 2;
1626    difference_type __sz2 = __sz - __sz1;
1627    __node_pointer __t = _VSTD::next(iterator(__f1), __sz1 - 1).__get_unsafe_node_pointer();
1628    __node_pointer __f2 = __t->__next_;
1629    __t->__next_ = nullptr;
1630    return __merge(__sort(__f1, __sz1, __comp),
1631                   __sort(__f2, __sz2, __comp), __comp);
1632}
1633
1634template <class _Tp, class _Alloc>
1635void
1636forward_list<_Tp, _Alloc>::reverse() _NOEXCEPT
1637{
1638    __node_pointer __p = base::__before_begin()->__next_;
1639    if (__p != nullptr)
1640    {
1641        __node_pointer __f = __p->__next_;
1642        __p->__next_ = nullptr;
1643        while (__f != nullptr)
1644        {
1645            __node_pointer __t = __f->__next_;
1646            __f->__next_ = __p;
1647            __p = __f;
1648            __f = __t;
1649        }
1650        base::__before_begin()->__next_ = __p;
1651    }
1652}
1653
1654template <class _Tp, class _Alloc>
1655bool operator==(const forward_list<_Tp, _Alloc>& __x,
1656                const forward_list<_Tp, _Alloc>& __y)
1657{
1658    typedef forward_list<_Tp, _Alloc> _Cp;
1659    typedef typename _Cp::const_iterator _Ip;
1660    _Ip __ix = __x.begin();
1661    _Ip __ex = __x.end();
1662    _Ip __iy = __y.begin();
1663    _Ip __ey = __y.end();
1664    for (; __ix != __ex && __iy != __ey; ++__ix, ++__iy)
1665        if (!(*__ix == *__iy))
1666            return false;
1667    return (__ix == __ex) == (__iy == __ey);
1668}
1669
1670template <class _Tp, class _Alloc>
1671inline _LIBCPP_INLINE_VISIBILITY
1672bool operator!=(const forward_list<_Tp, _Alloc>& __x,
1673                const forward_list<_Tp, _Alloc>& __y)
1674{
1675    return !(__x == __y);
1676}
1677
1678template <class _Tp, class _Alloc>
1679inline _LIBCPP_INLINE_VISIBILITY
1680bool operator< (const forward_list<_Tp, _Alloc>& __x,
1681                const forward_list<_Tp, _Alloc>& __y)
1682{
1683    return _VSTD::lexicographical_compare(__x.begin(), __x.end(),
1684                                         __y.begin(), __y.end());
1685}
1686
1687template <class _Tp, class _Alloc>
1688inline _LIBCPP_INLINE_VISIBILITY
1689bool operator> (const forward_list<_Tp, _Alloc>& __x,
1690                const forward_list<_Tp, _Alloc>& __y)
1691{
1692    return __y < __x;
1693}
1694
1695template <class _Tp, class _Alloc>
1696inline _LIBCPP_INLINE_VISIBILITY
1697bool operator>=(const forward_list<_Tp, _Alloc>& __x,
1698                const forward_list<_Tp, _Alloc>& __y)
1699{
1700    return !(__x < __y);
1701}
1702
1703template <class _Tp, class _Alloc>
1704inline _LIBCPP_INLINE_VISIBILITY
1705bool operator<=(const forward_list<_Tp, _Alloc>& __x,
1706                const forward_list<_Tp, _Alloc>& __y)
1707{
1708    return !(__y < __x);
1709}
1710
1711template <class _Tp, class _Alloc>
1712inline _LIBCPP_INLINE_VISIBILITY
1713void
1714swap(forward_list<_Tp, _Alloc>& __x, forward_list<_Tp, _Alloc>& __y)
1715    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1716{
1717    __x.swap(__y);
1718}
1719
1720_LIBCPP_END_NAMESPACE_STD
1721
1722#endif  // _LIBCPP_FORWARD_LIST
1723