libstdc++
debug/forward_list
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00001 // <forward_list> -*- C++ -*-
00002 
00003 // Copyright (C) 2010 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /** @file debug/forward_list
00026  *  This file is a GNU debug extension to the Standard C++ Library.
00027  */
00028 
00029 #ifndef _GLIBCXX_DEBUG_FORWARD_LIST
00030 #define _GLIBCXX_DEBUG_FORWARD_LIST 1
00031 
00032 #pragma GCC system_header
00033 
00034 #include <forward_list>
00035 #include <debug/safe_sequence.h>
00036 #include <debug/safe_iterator.h>
00037 
00038 namespace std _GLIBCXX_VISIBILITY(default)
00039 {
00040 namespace __debug
00041 {
00042   /// Class std::forward_list with safety/checking/debug instrumentation.
00043   template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
00044     class forward_list
00045     : public _GLIBCXX_STD_C::forward_list<_Tp, _Alloc>,
00046       public __gnu_debug::_Safe_sequence<forward_list<_Tp, _Alloc> >
00047     {
00048       typedef _GLIBCXX_STD_C::forward_list<_Tp, _Alloc> _Base;
00049 
00050       typedef typename _Base::iterator       _Base_iterator;
00051       typedef typename _Base::const_iterator _Base_const_iterator;
00052     public:
00053       typedef typename _Base::reference             reference;
00054       typedef typename _Base::const_reference       const_reference;
00055 
00056       typedef __gnu_debug::_Safe_iterator<_Base_iterator,
00057                       forward_list> iterator;
00058       typedef __gnu_debug::_Safe_iterator<_Base_const_iterator,
00059                       forward_list> const_iterator;
00060 
00061       typedef typename _Base::size_type             size_type;
00062       typedef typename _Base::difference_type       difference_type;
00063 
00064       typedef _Tp                                   value_type;
00065       typedef _Alloc                                allocator_type;
00066       typedef typename _Base::pointer               pointer;
00067       typedef typename _Base::const_pointer         const_pointer;
00068 
00069       // 23.2.3.1 construct/copy/destroy:
00070       explicit
00071       forward_list(const _Alloc& __al = _Alloc())
00072       : _Base(__al) { }
00073 
00074       forward_list(const forward_list& __list, const _Alloc& __al)
00075       : _Base(__list, __al)
00076       { }
00077 
00078       forward_list(forward_list&& __list, const _Alloc& __al)
00079       : _Base(std::move(__list._M_base()), __al)
00080       {
00081     this->_M_swap(__list);
00082       }
00083 
00084       explicit
00085       forward_list(size_type __n)
00086       : _Base(__n)
00087       { }
00088 
00089       forward_list(size_type __n, const _Tp& __value,
00090                    const _Alloc& __al = _Alloc())
00091       : _Base(__n, __value, __al)
00092       { }
00093 
00094       template<typename _InputIterator>
00095         forward_list(_InputIterator __first, _InputIterator __last,
00096                      const _Alloc& __al = _Alloc())
00097         : _Base(__gnu_debug::__base(__gnu_debug::__check_valid_range(__first,
00098                                      __last)),
00099         __gnu_debug::__base(__last), __al)
00100         { }
00101 
00102       forward_list(const forward_list& __list)
00103       : _Base(__list)
00104       { }
00105 
00106       forward_list(forward_list&& __list) noexcept
00107       : _Base(std::move(__list._M_base()))
00108       {
00109     this->_M_swap(__list);
00110       }
00111 
00112       forward_list(std::initializer_list<_Tp> __il,
00113                    const _Alloc& __al = _Alloc())
00114       : _Base(__il, __al)
00115       { }
00116 
00117       ~forward_list() noexcept
00118       { }
00119 
00120       forward_list&
00121       operator=(const forward_list& __list)
00122       {
00123     static_cast<_Base&>(*this) = __list;
00124     this->_M_invalidate_all();
00125     return *this;
00126       }
00127 
00128       forward_list&
00129       operator=(forward_list&& __list)
00130       {
00131     // NB: DR 1204.
00132     // NB: DR 675.
00133     clear();
00134     swap(__list);
00135     return *this;
00136       }
00137 
00138       forward_list&
00139       operator=(std::initializer_list<_Tp> __il)
00140       {
00141     static_cast<_Base&>(*this) = __il;
00142     this->_M_invalidate_all();
00143         return *this;
00144       }
00145 
00146       template<typename _InputIterator>
00147         void
00148         assign(_InputIterator __first, _InputIterator __last)
00149         {
00150       __glibcxx_check_valid_range(__first, __last);
00151       _Base::assign(__gnu_debug::__base(__first),
00152             __gnu_debug::__base(__last));
00153       this->_M_invalidate_all();
00154         }
00155 
00156       void
00157       assign(size_type __n, const _Tp& __val)
00158       {
00159     _Base::assign(__n, __val);
00160     this->_M_invalidate_all();
00161       }
00162 
00163       void
00164       assign(std::initializer_list<_Tp> __il)
00165       {
00166     _Base::assign(__il);
00167     this->_M_invalidate_all();
00168       }
00169 
00170       using _Base::get_allocator;
00171 
00172       // iterators:
00173 
00174       iterator
00175       before_begin() noexcept
00176       { return iterator(_Base::before_begin(), this); }
00177 
00178       const_iterator
00179       before_begin() const noexcept
00180       { return const_iterator(_Base::before_begin(), this); }
00181 
00182       iterator
00183       begin() noexcept
00184       { return iterator(_Base::begin(), this); }
00185 
00186       const_iterator
00187       begin() const noexcept
00188       { return const_iterator(_Base::begin(), this); }
00189 
00190       iterator
00191       end() noexcept
00192       { return iterator(_Base::end(), this); }
00193 
00194       const_iterator
00195       end() const noexcept
00196       { return const_iterator(_Base::end(), this); }
00197 
00198       const_iterator
00199       cbegin() const noexcept
00200       { return const_iterator(_Base::cbegin(), this); }
00201 
00202       const_iterator
00203       cbefore_begin() const noexcept
00204       { return const_iterator(_Base::cbefore_begin(), this); }
00205 
00206       const_iterator
00207       cend() const noexcept
00208       { return const_iterator(_Base::cend(), this); }
00209 
00210       using _Base::empty;
00211       using _Base::max_size;
00212 
00213       // element access:
00214 
00215       reference
00216       front()
00217       {
00218     __glibcxx_check_nonempty();
00219     return _Base::front();
00220       }
00221 
00222       const_reference
00223       front() const
00224       {
00225     __glibcxx_check_nonempty();
00226     return _Base::front();
00227       }
00228 
00229       // modifiers:
00230 
00231       using _Base::emplace_front;
00232       using _Base::push_front;
00233 
00234       void
00235       pop_front()
00236       {
00237     __glibcxx_check_nonempty();
00238     this->_M_invalidate_if([this](_Base_const_iterator __it)
00239       { return __it == this->_M_base().cbegin(); });
00240     _Base::pop_front();
00241       }
00242 
00243       template<typename... _Args>
00244     iterator
00245     emplace_after(const_iterator __pos, _Args&&... __args)
00246     {
00247       __glibcxx_check_insert_after(__pos);
00248       return iterator(_Base::emplace_after(__pos.base(),
00249                     std::forward<_Args>(__args)...),
00250               this);
00251         }
00252 
00253       iterator
00254       insert_after(const_iterator __pos, const _Tp& __val)
00255       {
00256     __glibcxx_check_insert_after(__pos);
00257     return iterator(_Base::insert_after(__pos.base(), __val), this);
00258       }
00259 
00260       iterator
00261       insert_after(const_iterator __pos, _Tp&& __val)
00262       {
00263     __glibcxx_check_insert_after(__pos);
00264     return iterator(_Base::insert_after(__pos.base(), std::move(__val)),
00265                 this);
00266       }
00267 
00268       iterator
00269       insert_after(const_iterator __pos, size_type __n, const _Tp& __val)
00270       {
00271     __glibcxx_check_insert_after(__pos);
00272     return iterator(_Base::insert_after(__pos.base(), __n, __val),
00273                 this);
00274       }
00275 
00276       template<typename _InputIterator>
00277         iterator
00278         insert_after(const_iterator __pos,
00279                      _InputIterator __first, _InputIterator __last)
00280         {
00281       __glibcxx_check_insert_range_after(__pos, __first, __last);
00282       return iterator(_Base::insert_after(__pos.base(),
00283                           __gnu_debug::__base(__first),
00284                           __gnu_debug::__base(__last)),
00285               this);
00286         }
00287 
00288       iterator
00289       insert_after(const_iterator __pos, std::initializer_list<_Tp> __il)
00290       {
00291     __glibcxx_check_insert_after(__pos);
00292     return iterator(_Base::insert_after(__pos.base(), __il), this);
00293       }
00294 
00295     private:
00296       _Base_iterator
00297       _M_erase_after(_Base_const_iterator __pos)
00298       {
00299     _Base_const_iterator __next = std::next(__pos);
00300     this->_M_invalidate_if([__next](_Base_const_iterator __it)
00301       { return __it == __next; });
00302     return _Base::erase_after(__pos);
00303       }
00304     public:
00305       iterator
00306       erase_after(const_iterator __pos)
00307       {
00308     __glibcxx_check_erase_after(__pos);
00309     return iterator(_M_erase_after(__pos.base()), this);
00310       }
00311 
00312       iterator
00313       erase_after(const_iterator __pos, const_iterator __last)
00314       {
00315     __glibcxx_check_erase_range_after(__pos, __last);
00316     for (_Base_const_iterator __victim = std::next(__pos.base());
00317         __victim != __last.base(); ++__victim)
00318       {
00319         _GLIBCXX_DEBUG_VERIFY(__victim != _Base::end(),
00320                   _M_message(__gnu_debug::__msg_valid_range2)
00321                   ._M_sequence(*this, "this")
00322                   ._M_iterator(__pos, "pos")
00323                   ._M_iterator(__last, "last"));
00324         this->_M_invalidate_if([__victim](_Base_const_iterator __it)
00325           { return __it == __victim; });
00326       }
00327     return iterator(_Base::erase_after(__pos.base(), __last.base()), this);
00328       }
00329 
00330       void
00331       swap(forward_list& __list)
00332       {
00333     _Base::swap(__list);
00334     this->_M_swap(__list);
00335       }
00336 
00337       void
00338       resize(size_type __sz)
00339       {
00340     this->_M_detach_singular();
00341 
00342     // if __sz < size(), invalidate all iterators in [begin+__sz, end()
00343     _Base_iterator __victim = _Base::begin();
00344     _Base_iterator __end = _Base::end();
00345     for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
00346       ++__victim;
00347 
00348     for (; __victim != __end; ++__victim)
00349       {
00350         this->_M_invalidate_if([__victim](_Base_const_iterator __it)
00351           { return __it == __victim; });
00352       }
00353 
00354     __try
00355       {
00356         _Base::resize(__sz);
00357       }
00358     __catch(...)
00359       {
00360         this->_M_revalidate_singular();
00361         __throw_exception_again;
00362           }
00363       }
00364 
00365       void
00366       resize(size_type __sz, const value_type& __val)
00367       {
00368     this->_M_detach_singular();
00369 
00370     // if __sz < size(), invalidate all iterators in [begin+__sz, end())
00371     _Base_iterator __victim = _Base::begin();
00372     _Base_iterator __end = _Base::end();
00373     for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
00374       ++__victim;
00375 
00376     for (; __victim != __end; ++__victim)
00377       {
00378         this->_M_invalidate_if([__victim](_Base_const_iterator __it)
00379           { return __it == __victim; });
00380       }
00381 
00382     __try
00383       {
00384         _Base::resize(__sz, __val);
00385       }
00386     __catch(...)
00387       {
00388         this->_M_revalidate_singular();
00389         __throw_exception_again;
00390           }
00391       }
00392 
00393       void
00394       clear() noexcept
00395       {
00396     _Base::clear();
00397     this->_M_invalidate_all();
00398       }
00399 
00400       // 23.2.3.5 forward_list operations:
00401       void
00402       splice_after(const_iterator __pos, forward_list&& __list)
00403       {
00404         __glibcxx_check_insert_after(__pos);
00405     _GLIBCXX_DEBUG_VERIFY(&__list != this,
00406                   _M_message(__gnu_debug::__msg_self_splice)
00407                   ._M_sequence(*this, "this"));
00408     this->_M_transfer_from_if(__list, [&__list](_Base_const_iterator __it)
00409       {
00410         return __it != __list._M_base().cbefore_begin()
00411            && __it != __list._M_base().end();
00412       });
00413     _Base::splice_after(__pos.base(), std::move(__list._M_base()));
00414       }
00415 
00416       void
00417       splice_after(const_iterator __pos, forward_list& __list)
00418       { splice_after(__pos, std::move(__list)); }
00419 
00420       void
00421       splice_after(const_iterator __pos, forward_list&& __list,
00422            const_iterator __i)
00423       {
00424     __glibcxx_check_insert_after(__pos);
00425     _GLIBCXX_DEBUG_VERIFY(__i._M_before_dereferenceable(),
00426                   _M_message(__gnu_debug::__msg_splice_bad)
00427                   ._M_iterator(__i, "__i"));
00428     _GLIBCXX_DEBUG_VERIFY(__i._M_attached_to(&__list),
00429                   _M_message(__gnu_debug::__msg_splice_other)
00430                   ._M_iterator(__i, "__i")
00431                   ._M_sequence(__list, "__list"));
00432 
00433     // _GLIBCXX_RESOLVE_LIB_DEFECTS
00434     // 250. splicing invalidates iterators
00435     _Base_const_iterator __next = std::next(__i.base());
00436     this->_M_transfer_from_if(__list, [__next](_Base_const_iterator __it)
00437       { return __it == __next; });
00438     _Base::splice_after(__pos.base(), std::move(__list._M_base()),
00439                 __i.base());
00440       }
00441 
00442       void
00443       splice_after(const_iterator __pos, forward_list& __list,
00444            const_iterator __i)
00445       { splice_after(__pos, std::move(__list), __i); }
00446 
00447       void
00448       splice_after(const_iterator __pos, forward_list&& __list,
00449            const_iterator __before, const_iterator __last)
00450       {
00451         __glibcxx_check_insert_after(__pos);
00452     __glibcxx_check_valid_range(__before, __last);
00453     _GLIBCXX_DEBUG_VERIFY(__before._M_attached_to(&__list),
00454                   _M_message(__gnu_debug::__msg_splice_other)
00455                   ._M_sequence(__list, "list")
00456                   ._M_iterator(__before, "before"));
00457     _GLIBCXX_DEBUG_VERIFY(__before._M_dereferenceable()
00458                   || __before._M_is_before_begin(),
00459                   _M_message(__gnu_debug::__msg_valid_range2)
00460                   ._M_sequence(__list, "list")
00461                   ._M_iterator(__before, "before")
00462                   ._M_iterator(__last, "last"));
00463     _GLIBCXX_DEBUG_VERIFY(__before != __last,
00464                   _M_message(__gnu_debug::__msg_valid_range2)
00465                   ._M_sequence(__list, "list")
00466                   ._M_iterator(__before, "before")
00467                   ._M_iterator(__last, "last"));
00468 
00469     for (_Base_const_iterator __tmp = std::next(__before.base());
00470          __tmp != __last.base(); ++__tmp)
00471       {
00472         _GLIBCXX_DEBUG_VERIFY(__tmp != __list._M_base().end(),
00473                   _M_message(__gnu_debug::__msg_valid_range2)
00474                   ._M_sequence(__list, "list")
00475                   ._M_iterator(__before, "before")
00476                   ._M_iterator(__last, "last"));
00477         _GLIBCXX_DEBUG_VERIFY(&__list != this || __tmp != __pos.base(),
00478                                   _M_message(__gnu_debug::__msg_splice_overlap)
00479                                   ._M_iterator(__tmp, "position")
00480                   ._M_iterator(__before, "before")
00481                   ._M_iterator(__last, "last"));
00482         // _GLIBCXX_RESOLVE_LIB_DEFECTS
00483         // 250. splicing invalidates iterators
00484         this->_M_transfer_from_if(__list, [__tmp](_Base_const_iterator __it)
00485           { return __it == __tmp; });
00486       }
00487 
00488     _Base::splice_after(__pos.base(), std::move(__list._M_base()),
00489                 __before.base(), __last.base());
00490       }
00491 
00492       void
00493       splice_after(const_iterator __pos, forward_list& __list,
00494            const_iterator __before, const_iterator __last)
00495       { splice_after(__pos, std::move(__list), __before, __last); }
00496 
00497       void
00498       remove(const _Tp& __val)
00499       {
00500     _Base_iterator __x = _Base::before_begin();
00501     _Base_iterator __old = __x++;
00502     while (__x != _Base::end())
00503       {
00504         if (*__x == __val)
00505           __x = _M_erase_after(__old);
00506         else
00507           __old = __x++;
00508       }
00509       }
00510 
00511       template<typename _Pred>
00512         void
00513         remove_if(_Pred __pred)
00514     {
00515       _Base_iterator __x = _Base::before_begin();
00516       _Base_iterator __old = __x++;
00517       while (__x != _Base::end())
00518         {
00519           if (__pred(*__x))
00520         __x = _M_erase_after(__old);
00521           else
00522         __old = __x++;
00523         }
00524     }
00525 
00526       void
00527       unique()
00528       {
00529     _Base_iterator __first = _Base::begin();
00530     _Base_iterator __last = _Base::end();
00531     if (__first == __last)
00532       return;
00533     _Base_iterator __next = std::next(__first);
00534     while (__next != __last)
00535       {
00536         if (*__first == *__next)
00537           __next = _M_erase_after(__first);
00538         else
00539           __first = __next++;
00540       }
00541       }
00542 
00543       template<typename _BinPred>
00544         void
00545         unique(_BinPred __binary_pred)
00546     {
00547       _Base_iterator __first = _Base::begin();
00548       _Base_iterator __last = _Base::end();
00549       if (__first == __last)
00550         return;
00551       _Base_iterator __next = std::next(__first);
00552       while (__next != __last)
00553         {
00554           if (__binary_pred(*__first, *__next))
00555         __next = _M_erase_after(__first);
00556           else
00557         __first = __next++;
00558         }
00559     }
00560 
00561       void
00562       merge(forward_list&& __list)
00563       {
00564     if (this != &__list)
00565     {
00566       __glibcxx_check_sorted(_Base::begin(), _Base::end());
00567       __glibcxx_check_sorted(__list._M_base().begin(),
00568                  __list._M_base().end());
00569       this->_M_transfer_from_if(__list, [&__list](_Base_const_iterator __it)
00570         {
00571           return __it != __list._M_base().cbefore_begin()
00572              && __it != __list._M_base().cend();
00573         });
00574       _Base::merge(std::move(__list._M_base()));
00575     }
00576       }
00577 
00578       void
00579       merge(forward_list& __list)
00580       { merge(std::move(__list)); }
00581 
00582       template<typename _Comp>
00583         void
00584         merge(forward_list&& __list, _Comp __comp)
00585     {
00586       if (this != &__list)
00587       {
00588         __glibcxx_check_sorted_pred(_Base::begin(), _Base::end(), __comp);
00589         __glibcxx_check_sorted_pred(__list._M_base().begin(),
00590                     __list._M_base().end(), __comp);
00591         this->_M_transfer_from_if(__list,
00592                       [&__list](_Base_const_iterator __it)
00593           {
00594             return __it != __list._M_base().cbefore_begin()
00595                && __it != __list._M_base().cend();
00596           });
00597         _Base::merge(std::move(__list._M_base()), __comp);
00598       }
00599     }
00600 
00601       template<typename _Comp>
00602         void
00603         merge(forward_list& __list, _Comp __comp)
00604         { merge(std::move(__list), __comp); }
00605 
00606       using _Base::sort;
00607       using _Base::reverse;
00608 
00609       _Base&
00610       _M_base() noexcept       { return *this; }
00611 
00612       const _Base&
00613       _M_base() const noexcept { return *this; }
00614 
00615     private:
00616       void
00617       _M_invalidate_all()
00618       {
00619     this->_M_invalidate_if([this](_Base_const_iterator __it)
00620       {
00621         return __it != this->_M_base().cbefore_begin()
00622            && __it != this->_M_base().cend();
00623       });
00624       }
00625       typedef __gnu_debug::_Safe_iterator_base _Safe_iterator_base;
00626       static void
00627       _M_swap_aux(forward_list& __lhs,
00628           _Safe_iterator_base*& __lhs_iterators,
00629           forward_list& __rhs,
00630           _Safe_iterator_base*& __rhs_iterators);
00631       void _M_swap(forward_list& __list);
00632     };
00633 
00634    template<typename _Tp, typename _Alloc>
00635     void
00636     forward_list<_Tp, _Alloc>::
00637     _M_swap_aux(forward_list<_Tp, _Alloc>& __lhs,
00638         __gnu_debug::_Safe_iterator_base*& __lhs_iterators,
00639         forward_list<_Tp, _Alloc>& __rhs,
00640         __gnu_debug::_Safe_iterator_base*& __rhs_iterators)
00641     {
00642       using __gnu_debug::_Safe_iterator_base;
00643       _Safe_iterator_base* __bbegin_its = 0;
00644       _Safe_iterator_base* __last_bbegin = 0;
00645       for (_Safe_iterator_base* __iter = __lhs_iterators; __iter;)
00646     {
00647       // Even iterator are casted to const_iterator, not a problem.
00648       const_iterator* __victim = static_cast<const_iterator*>(__iter);
00649       __iter = __iter->_M_next;
00650       if (__victim->base() == __rhs._M_base().cbefore_begin())
00651         {
00652           __victim->_M_unlink();
00653           if (__lhs_iterators == __victim)
00654         __lhs_iterators = __victim->_M_next;
00655           if (__bbegin_its)
00656         {
00657           __victim->_M_next = __bbegin_its;
00658           __bbegin_its->_M_prior = __victim;
00659         }
00660           else
00661         __last_bbegin = __victim;
00662           __bbegin_its = __victim;
00663         }
00664       else
00665         __victim->_M_sequence = &__lhs;
00666     }
00667 
00668       if (__bbegin_its)
00669     {
00670       if (__rhs_iterators)
00671         {
00672           __rhs_iterators->_M_prior = __last_bbegin;
00673           __last_bbegin->_M_next = __rhs_iterators;
00674         }
00675       __rhs_iterators = __bbegin_its;
00676     }
00677     }
00678 
00679   /* Special forward_list _M_swap version that do not swap the
00680    * before-begin ownership.*/
00681   template<typename _Tp, typename _Alloc>
00682     void
00683     forward_list<_Tp, _Alloc>::
00684     _M_swap(forward_list<_Tp, _Alloc>& __list)
00685     {
00686       __gnu_cxx::__scoped_lock sentry(this->_M_get_mutex());
00687       std::swap(this->_M_iterators, __list._M_iterators);
00688       std::swap(this->_M_const_iterators, __list._M_const_iterators);
00689       // Useless, always 1 on forward_list
00690       //std::swap(this->_M_version, __list._M_version);
00691       _Safe_iterator_base* __this_its = this->_M_iterators;
00692       _M_swap_aux(__list, __list._M_iterators, *this, this->_M_iterators);
00693       _Safe_iterator_base* __this_const_its = this->_M_const_iterators;
00694       _M_swap_aux(__list, __list._M_const_iterators, *this,
00695           this->_M_const_iterators);
00696       _M_swap_aux(*this, __this_its, __list, __list._M_iterators);
00697       _M_swap_aux(*this, __this_const_its, __list, __list._M_const_iterators);
00698     }
00699 
00700   template<typename _Tp, typename _Alloc>
00701     bool
00702     operator==(const forward_list<_Tp, _Alloc>& __lx,
00703                const forward_list<_Tp, _Alloc>& __ly)
00704     { return __lx._M_base() == __ly._M_base(); }
00705 
00706   template<typename _Tp, typename _Alloc>
00707     inline bool
00708     operator<(const forward_list<_Tp, _Alloc>& __lx,
00709               const forward_list<_Tp, _Alloc>& __ly)
00710     { return __lx._M_base() < __ly._M_base(); }
00711 
00712   template<typename _Tp, typename _Alloc>
00713     inline bool
00714     operator!=(const forward_list<_Tp, _Alloc>& __lx,
00715                const forward_list<_Tp, _Alloc>& __ly)
00716     { return !(__lx == __ly); }
00717 
00718   /// Based on operator<
00719   template<typename _Tp, typename _Alloc>
00720     inline bool
00721     operator>(const forward_list<_Tp, _Alloc>& __lx,
00722               const forward_list<_Tp, _Alloc>& __ly)
00723     { return (__ly < __lx); }
00724 
00725   /// Based on operator<
00726   template<typename _Tp, typename _Alloc>
00727     inline bool
00728     operator>=(const forward_list<_Tp, _Alloc>& __lx,
00729                const forward_list<_Tp, _Alloc>& __ly)
00730     { return !(__lx < __ly); }
00731 
00732   /// Based on operator<
00733   template<typename _Tp, typename _Alloc>
00734     inline bool
00735     operator<=(const forward_list<_Tp, _Alloc>& __lx,
00736                const forward_list<_Tp, _Alloc>& __ly)
00737     { return !(__ly < __lx); }
00738 
00739   /// See std::forward_list::swap().
00740   template<typename _Tp, typename _Alloc>
00741     inline void
00742     swap(forward_list<_Tp, _Alloc>& __lx,
00743      forward_list<_Tp, _Alloc>& __ly)
00744     { __lx.swap(__ly); }
00745 
00746 } // namespace __debug
00747 } // namespace std
00748 
00749 namespace __gnu_debug
00750 {
00751   template<class _Tp, class _Alloc>
00752     struct _BeforeBeginHelper<std::__debug::forward_list<_Tp, _Alloc> >
00753     {
00754       typedef std::__debug::forward_list<_Tp, _Alloc> _Sequence;
00755       typedef typename _Sequence::const_iterator _It;
00756       typedef typename _It::iterator_type _BaseIt;
00757 
00758       static bool
00759       _S_Is(_BaseIt __it, const _Sequence* __seq)
00760       { return __it == __seq->_M_base().cbefore_begin(); }
00761 
00762       static bool
00763       _S_Is_Beginnest(_BaseIt __it, const _Sequence* __seq)
00764       { return _S_Is(__it, __seq); }
00765     };
00766 }
00767 
00768 #endif