stl_list.h

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// List implementation -*- C++ -*-

// Copyright (C) 2001-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1996,1997
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

#ifndef _STL_LIST_H
#define _STL_LIST_H 1

#include <bits/concept_check.h>
#if __cplusplus >= 201103L
#include <initializer_list>
#endif

namespace std _GLIBCXX_VISIBILITY(default)
{
  namespace __detail
  {
  _GLIBCXX_BEGIN_NAMESPACE_VERSION

    // Supporting structures are split into common and templated
    // types; the latter publicly inherits from the former in an
    // effort to reduce code duplication.  This results in some
    // "needless" static_cast'ing later on, but it's all safe
    // downcasting.

    struct _List_node_base
    {
      _List_node_base* _M_next;
      _List_node_base* _M_prev;

      static void
      swap(_List_node_base& __x, _List_node_base& __y) _GLIBCXX_USE_NOEXCEPT;

      void
      _M_transfer(_List_node_base* const __first,
          _List_node_base* const __last) _GLIBCXX_USE_NOEXCEPT;

      void
      _M_reverse() _GLIBCXX_USE_NOEXCEPT;

      void
      _M_hook(_List_node_base* const __position) _GLIBCXX_USE_NOEXCEPT;

      void
      _M_unhook() _GLIBCXX_USE_NOEXCEPT;
    };

  _GLIBCXX_END_NAMESPACE_VERSION
  } // namespace detail

_GLIBCXX_BEGIN_NAMESPACE_CONTAINER

  template<typename _Tp>
    struct _List_node : public __detail::_List_node_base
    {
      _Tp _M_data;

#if __cplusplus >= 201103L
      template<typename... _Args>
        _List_node(_Args&&... __args)
    : __detail::_List_node_base(), _M_data(std::forward<_Args>(__args)...) 
        { }
#endif
    };

  template<typename _Tp>
    struct _List_iterator
    {
      typedef _List_iterator<_Tp>                _Self;
      typedef _List_node<_Tp>                    _Node;

      typedef ptrdiff_t                          difference_type;
      typedef std::bidirectional_iterator_tag    iterator_category;
      typedef _Tp                                value_type;
      typedef _Tp*                               pointer;
      typedef _Tp&                               reference;

      _List_iterator()
      : _M_node() { }

      explicit
      _List_iterator(__detail::_List_node_base* __x)
      : _M_node(__x) { }

      // Must downcast from _List_node_base to _List_node to get to _M_data.
      reference
      operator*() const
      { return static_cast<_Node*>(_M_node)->_M_data; }

      pointer
      operator->() const
      { return std::__addressof(static_cast<_Node*>(_M_node)->_M_data); }

      _Self&
      operator++()
      {
    _M_node = _M_node->_M_next;
    return *this;
      }

      _Self
      operator++(int)
      {
    _Self __tmp = *this;
    _M_node = _M_node->_M_next;
    return __tmp;
      }

      _Self&
      operator--()
      {
    _M_node = _M_node->_M_prev;
    return *this;
      }

      _Self
      operator--(int)
      {
    _Self __tmp = *this;
    _M_node = _M_node->_M_prev;
    return __tmp;
      }

      bool
      operator==(const _Self& __x) const
      { return _M_node == __x._M_node; }

      bool
      operator!=(const _Self& __x) const
      { return _M_node != __x._M_node; }

      // The only member points to the %list element.
      __detail::_List_node_base* _M_node;
    };

  template<typename _Tp>
    struct _List_const_iterator
    {
      typedef _List_const_iterator<_Tp>          _Self;
      typedef const _List_node<_Tp>              _Node;
      typedef _List_iterator<_Tp>                iterator;

      typedef ptrdiff_t                          difference_type;
      typedef std::bidirectional_iterator_tag    iterator_category;
      typedef _Tp                                value_type;
      typedef const _Tp*                         pointer;
      typedef const _Tp&                         reference;

      _List_const_iterator()
      : _M_node() { }

      explicit
      _List_const_iterator(const __detail::_List_node_base* __x)
      : _M_node(__x) { }

      _List_const_iterator(const iterator& __x)
      : _M_node(__x._M_node) { }

      // Must downcast from List_node_base to _List_node to get to
      // _M_data.
      reference
      operator*() const
      { return static_cast<_Node*>(_M_node)->_M_data; }

      pointer
      operator->() const
      { return std::__addressof(static_cast<_Node*>(_M_node)->_M_data); }

      _Self&
      operator++()
      {
    _M_node = _M_node->_M_next;
    return *this;
      }

      _Self
      operator++(int)
      {
    _Self __tmp = *this;
    _M_node = _M_node->_M_next;
    return __tmp;
      }

      _Self&
      operator--()
      {
    _M_node = _M_node->_M_prev;
    return *this;
      }

      _Self
      operator--(int)
      {
    _Self __tmp = *this;
    _M_node = _M_node->_M_prev;
    return __tmp;
      }

      bool
      operator==(const _Self& __x) const
      { return _M_node == __x._M_node; }

      bool
      operator!=(const _Self& __x) const
      { return _M_node != __x._M_node; }

      // The only member points to the %list element.
      const __detail::_List_node_base* _M_node;
    };

  template<typename _Val>
    inline bool
    operator==(const _List_iterator<_Val>& __x,
           const _List_const_iterator<_Val>& __y)
    { return __x._M_node == __y._M_node; }

  template<typename _Val>
    inline bool
    operator!=(const _List_iterator<_Val>& __x,
               const _List_const_iterator<_Val>& __y)
    { return __x._M_node != __y._M_node; }


  template<typename _Tp, typename _Alloc>
    class _List_base
    {
    protected:
      // NOTA BENE
      // The stored instance is not actually of "allocator_type"'s
      // type.  Instead we rebind the type to
      // Allocator<List_node<Tp>>, which according to [20.1.5]/4
      // should probably be the same.  List_node<Tp> is not the same
      // size as Tp (it's two pointers larger), and specializations on
      // Tp may go unused because List_node<Tp> is being bound
      // instead.
      //
      // We put this to the test in the constructors and in
      // get_allocator, where we use conversions between
      // allocator_type and _Node_alloc_type. The conversion is
      // required by table 32 in [20.1.5].
      typedef typename _Alloc::template rebind<_List_node<_Tp> >::other
        _Node_alloc_type;

      typedef typename _Alloc::template rebind<_Tp>::other _Tp_alloc_type;

      struct _List_impl
      : public _Node_alloc_type
      {
    __detail::_List_node_base _M_node;

    _List_impl()
    : _Node_alloc_type(), _M_node()
    { }

    _List_impl(const _Node_alloc_type& __a)
    : _Node_alloc_type(__a), _M_node()
    { }

#if __cplusplus >= 201103L
    _List_impl(_Node_alloc_type&& __a)
    : _Node_alloc_type(std::move(__a)), _M_node()
    { }
#endif
      };

      _List_impl _M_impl;

      _List_node<_Tp>*
      _M_get_node()
      { return _M_impl._Node_alloc_type::allocate(1); }

      void
      _M_put_node(_List_node<_Tp>* __p)
      { _M_impl._Node_alloc_type::deallocate(__p, 1); }

  public:
      typedef _Alloc allocator_type;

      _Node_alloc_type&
      _M_get_Node_allocator() _GLIBCXX_NOEXCEPT
      { return *static_cast<_Node_alloc_type*>(&_M_impl); }

      const _Node_alloc_type&
      _M_get_Node_allocator() const _GLIBCXX_NOEXCEPT
      { return *static_cast<const _Node_alloc_type*>(&_M_impl); }

      _Tp_alloc_type
      _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT
      { return _Tp_alloc_type(_M_get_Node_allocator()); }

      allocator_type
      get_allocator() const _GLIBCXX_NOEXCEPT
      { return allocator_type(_M_get_Node_allocator()); }

      _List_base()
      : _M_impl()
      { _M_init(); }

      _List_base(const _Node_alloc_type& __a)
      : _M_impl(__a)
      { _M_init(); }

#if __cplusplus >= 201103L
      _List_base(_List_base&& __x)
      : _M_impl(std::move(__x._M_get_Node_allocator()))
      {
    _M_init();
    __detail::_List_node_base::swap(_M_impl._M_node, __x._M_impl._M_node);
      }
#endif

      // This is what actually destroys the list.
      ~_List_base() _GLIBCXX_NOEXCEPT
      { _M_clear(); }

      void
      _M_clear();

      void
      _M_init()
      {
        this->_M_impl._M_node._M_next = &this->_M_impl._M_node;
        this->_M_impl._M_node._M_prev = &this->_M_impl._M_node;
      }
    };

  template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
    class list : protected _List_base<_Tp, _Alloc>
    {
      // concept requirements
      typedef typename _Alloc::value_type                _Alloc_value_type;
      __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
      __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)

      typedef _List_base<_Tp, _Alloc>                    _Base;
      typedef typename _Base::_Tp_alloc_type         _Tp_alloc_type;
      typedef typename _Base::_Node_alloc_type       _Node_alloc_type;

    public:
      typedef _Tp                                        value_type;
      typedef typename _Tp_alloc_type::pointer           pointer;
      typedef typename _Tp_alloc_type::const_pointer     const_pointer;
      typedef typename _Tp_alloc_type::reference         reference;
      typedef typename _Tp_alloc_type::const_reference   const_reference;
      typedef _List_iterator<_Tp>                        iterator;
      typedef _List_const_iterator<_Tp>                  const_iterator;
      typedef std::reverse_iterator<const_iterator>      const_reverse_iterator;
      typedef std::reverse_iterator<iterator>            reverse_iterator;
      typedef size_t                                     size_type;
      typedef ptrdiff_t                                  difference_type;
      typedef _Alloc                                     allocator_type;

    protected:
      // Note that pointers-to-_Node's can be ctor-converted to
      // iterator types.
      typedef _List_node<_Tp>                _Node;

      using _Base::_M_impl;
      using _Base::_M_put_node;
      using _Base::_M_get_node;
      using _Base::_M_get_Tp_allocator;
      using _Base::_M_get_Node_allocator;

#if __cplusplus < 201103L
      _Node*
      _M_create_node(const value_type& __x)
      {
    _Node* __p = this->_M_get_node();
    __try
      {
        _M_get_Tp_allocator().construct
          (std::__addressof(__p->_M_data), __x);
      }
    __catch(...)
      {
        _M_put_node(__p);
        __throw_exception_again;
      }
    return __p;
      }
#else
      template<typename... _Args>
        _Node*
        _M_create_node(_Args&&... __args)
    {
      _Node* __p = this->_M_get_node();
      __try
        {
          _M_get_Node_allocator().construct(__p,
                        std::forward<_Args>(__args)...);
        }
      __catch(...)
        {
          _M_put_node(__p);
          __throw_exception_again;
        }
      return __p;
    }
#endif

    public:
      // [23.2.2.1] construct/copy/destroy
      // (assign() and get_allocator() are also listed in this section)
      list()
      : _Base() { }

      explicit
      list(const allocator_type& __a)
      : _Base(_Node_alloc_type(__a)) { }

#if __cplusplus >= 201103L

      explicit
      list(size_type __n)
      : _Base()
      { _M_default_initialize(__n); }

      list(size_type __n, const value_type& __value,
       const allocator_type& __a = allocator_type())
      : _Base(_Node_alloc_type(__a))
      { _M_fill_initialize(__n, __value); }
#else

      explicit
      list(size_type __n, const value_type& __value = value_type(),
       const allocator_type& __a = allocator_type())
      : _Base(_Node_alloc_type(__a))
      { _M_fill_initialize(__n, __value); }
#endif

      list(const list& __x)
      : _Base(__x._M_get_Node_allocator())
      { _M_initialize_dispatch(__x.begin(), __x.end(), __false_type()); }

#if __cplusplus >= 201103L

      list(list&& __x) noexcept
      : _Base(std::move(__x)) { }

      list(initializer_list<value_type> __l,
           const allocator_type& __a = allocator_type())
      : _Base(_Node_alloc_type(__a))
      { _M_initialize_dispatch(__l.begin(), __l.end(), __false_type()); }
#endif

#if __cplusplus >= 201103L
      template<typename _InputIterator,
           typename = std::_RequireInputIter<_InputIterator>>
        list(_InputIterator __first, _InputIterator __last,
         const allocator_type& __a = allocator_type())
    : _Base(_Node_alloc_type(__a))
        { _M_initialize_dispatch(__first, __last, __false_type()); }
#else
      template<typename _InputIterator>
        list(_InputIterator __first, _InputIterator __last,
         const allocator_type& __a = allocator_type())
    : _Base(_Node_alloc_type(__a))
        { 
      // Check whether it's an integral type.  If so, it's not an iterator.
      typedef typename std::__is_integer<_InputIterator>::__type _Integral;
      _M_initialize_dispatch(__first, __last, _Integral());
    }
#endif

      list&
      operator=(const list& __x);

#if __cplusplus >= 201103L

      list&
      operator=(list&& __x)
      {
    // NB: DR 1204.
    // NB: DR 675.
    this->clear();
    this->swap(__x);
    return *this;
      }

      list&
      operator=(initializer_list<value_type> __l)
      {
    this->assign(__l.begin(), __l.end());
    return *this;
      }
#endif

      void
      assign(size_type __n, const value_type& __val)
      { _M_fill_assign(__n, __val); }

#if __cplusplus >= 201103L
      template<typename _InputIterator,
           typename = std::_RequireInputIter<_InputIterator>>
        void
        assign(_InputIterator __first, _InputIterator __last)
        { _M_assign_dispatch(__first, __last, __false_type()); }
#else
      template<typename _InputIterator>
        void
        assign(_InputIterator __first, _InputIterator __last)
        {
      // Check whether it's an integral type.  If so, it's not an iterator.
      typedef typename std::__is_integer<_InputIterator>::__type _Integral;
      _M_assign_dispatch(__first, __last, _Integral());
    }
#endif

#if __cplusplus >= 201103L

      void
      assign(initializer_list<value_type> __l)
      { this->assign(__l.begin(), __l.end()); }
#endif

      allocator_type
      get_allocator() const _GLIBCXX_NOEXCEPT
      { return _Base::get_allocator(); }

      // iterators
      iterator
      begin() _GLIBCXX_NOEXCEPT
      { return iterator(this->_M_impl._M_node._M_next); }

      const_iterator
      begin() const _GLIBCXX_NOEXCEPT
      { return const_iterator(this->_M_impl._M_node._M_next); }

      iterator
      end() _GLIBCXX_NOEXCEPT
      { return iterator(&this->_M_impl._M_node); }

      const_iterator
      end() const _GLIBCXX_NOEXCEPT
      { return const_iterator(&this->_M_impl._M_node); }

      reverse_iterator
      rbegin() _GLIBCXX_NOEXCEPT
      { return reverse_iterator(end()); }

      const_reverse_iterator
      rbegin() const _GLIBCXX_NOEXCEPT
      { return const_reverse_iterator(end()); }

      reverse_iterator
      rend() _GLIBCXX_NOEXCEPT
      { return reverse_iterator(begin()); }

      const_reverse_iterator
      rend() const _GLIBCXX_NOEXCEPT
      { return const_reverse_iterator(begin()); }

#if __cplusplus >= 201103L

      const_iterator
      cbegin() const noexcept
      { return const_iterator(this->_M_impl._M_node._M_next); }

      const_iterator
      cend() const noexcept
      { return const_iterator(&this->_M_impl._M_node); }

      const_reverse_iterator
      crbegin() const noexcept
      { return const_reverse_iterator(end()); }

      const_reverse_iterator
      crend() const noexcept
      { return const_reverse_iterator(begin()); }
#endif

      // [23.2.2.2] capacity
      bool
      empty() const _GLIBCXX_NOEXCEPT
      { return this->_M_impl._M_node._M_next == &this->_M_impl._M_node; }

      size_type
      size() const _GLIBCXX_NOEXCEPT
      { return std::distance(begin(), end()); }

      size_type
      max_size() const _GLIBCXX_NOEXCEPT
      { return _M_get_Node_allocator().max_size(); }

#if __cplusplus >= 201103L

      void
      resize(size_type __new_size);

      void
      resize(size_type __new_size, const value_type& __x);
#else

      void
      resize(size_type __new_size, value_type __x = value_type());
#endif

      // element access
      reference
      front()
      { return *begin(); }

      const_reference
      front() const
      { return *begin(); }

      reference
      back()
      { 
    iterator __tmp = end();
    --__tmp;
    return *__tmp;
      }

      const_reference
      back() const
      { 
    const_iterator __tmp = end();
    --__tmp;
    return *__tmp;
      }

      // [23.2.2.3] modifiers
      void
      push_front(const value_type& __x)
      { this->_M_insert(begin(), __x); }

#if __cplusplus >= 201103L
      void
      push_front(value_type&& __x)
      { this->_M_insert(begin(), std::move(__x)); }

      template<typename... _Args>
        void
        emplace_front(_Args&&... __args)
        { this->_M_insert(begin(), std::forward<_Args>(__args)...); }
#endif

      void
      pop_front()
      { this->_M_erase(begin()); }

      void
      push_back(const value_type& __x)
      { this->_M_insert(end(), __x); }

#if __cplusplus >= 201103L
      void
      push_back(value_type&& __x)
      { this->_M_insert(end(), std::move(__x)); }

      template<typename... _Args>
        void
        emplace_back(_Args&&... __args)
        { this->_M_insert(end(), std::forward<_Args>(__args)...); }
#endif

      void
      pop_back()
      { this->_M_erase(iterator(this->_M_impl._M_node._M_prev)); }

#if __cplusplus >= 201103L

      template<typename... _Args>
        iterator
        emplace(iterator __position, _Args&&... __args);
#endif

      iterator
      insert(iterator __position, const value_type& __x);

#if __cplusplus >= 201103L

      iterator
      insert(iterator __position, value_type&& __x)
      { return emplace(__position, std::move(__x)); }

      void
      insert(iterator __p, initializer_list<value_type> __l)
      { this->insert(__p, __l.begin(), __l.end()); }
#endif

      void
      insert(iterator __position, size_type __n, const value_type& __x)
      {
    list __tmp(__n, __x, get_allocator());
    splice(__position, __tmp);
      }

#if __cplusplus >= 201103L
      template<typename _InputIterator,
           typename = std::_RequireInputIter<_InputIterator>>
#else
      template<typename _InputIterator>
#endif
        void
        insert(iterator __position, _InputIterator __first,
           _InputIterator __last)
        {
      list __tmp(__first, __last, get_allocator());
      splice(__position, __tmp);
    }

      iterator
      erase(iterator __position);

      iterator
      erase(iterator __first, iterator __last)
      {
    while (__first != __last)
      __first = erase(__first);
    return __last;
      }

      void
      swap(list& __x)
      {
    __detail::_List_node_base::swap(this->_M_impl._M_node, 
                    __x._M_impl._M_node);

    // _GLIBCXX_RESOLVE_LIB_DEFECTS
    // 431. Swapping containers with unequal allocators.
    std::__alloc_swap<typename _Base::_Node_alloc_type>::
      _S_do_it(_M_get_Node_allocator(), __x._M_get_Node_allocator());
      }

      void
      clear() _GLIBCXX_NOEXCEPT
      {
        _Base::_M_clear();
        _Base::_M_init();
      }

      // [23.2.2.4] list operations
      void
#if __cplusplus >= 201103L
      splice(iterator __position, list&& __x)
#else
      splice(iterator __position, list& __x)
#endif
      {
    if (!__x.empty())
      {
        _M_check_equal_allocators(__x);

        this->_M_transfer(__position, __x.begin(), __x.end());
      }
      }

#if __cplusplus >= 201103L
      void
      splice(iterator __position, list& __x)
      { splice(__position, std::move(__x)); }
#endif

      void
#if __cplusplus >= 201103L
      splice(iterator __position, list&& __x, iterator __i)
#else
      splice(iterator __position, list& __x, iterator __i)
#endif
      {
    iterator __j = __i;
    ++__j;
    if (__position == __i || __position == __j)
      return;

    if (this != &__x)
      _M_check_equal_allocators(__x);

    this->_M_transfer(__position, __i, __j);
      }

#if __cplusplus >= 201103L
      void
      splice(iterator __position, list& __x, iterator __i)
      { splice(__position, std::move(__x), __i); }
#endif

      void
#if __cplusplus >= 201103L
      splice(iterator __position, list&& __x, iterator __first,
         iterator __last)
#else
      splice(iterator __position, list& __x, iterator __first,
         iterator __last)
#endif
      {
    if (__first != __last)
      {
        if (this != &__x)
          _M_check_equal_allocators(__x);

        this->_M_transfer(__position, __first, __last);
      }
      }

#if __cplusplus >= 201103L
      void
      splice(iterator __position, list& __x, iterator __first, iterator __last)
      { splice(__position, std::move(__x), __first, __last); }
#endif

      void
      remove(const _Tp& __value);

      template<typename _Predicate>
        void
        remove_if(_Predicate);

      void
      unique();

      template<typename _BinaryPredicate>
        void
        unique(_BinaryPredicate);

#if __cplusplus >= 201103L
      void
      merge(list&& __x);

      void
      merge(list& __x)
      { merge(std::move(__x)); }
#else
      void
      merge(list& __x);
#endif

#if __cplusplus >= 201103L
      template<typename _StrictWeakOrdering>
        void
        merge(list&& __x, _StrictWeakOrdering __comp);

      template<typename _StrictWeakOrdering>
        void
        merge(list& __x, _StrictWeakOrdering __comp)
        { merge(std::move(__x), __comp); }
#else
      template<typename _StrictWeakOrdering>
        void
        merge(list& __x, _StrictWeakOrdering __comp);
#endif

      void
      reverse() _GLIBCXX_NOEXCEPT
      { this->_M_impl._M_node._M_reverse(); }

      void
      sort();

      template<typename _StrictWeakOrdering>
        void
        sort(_StrictWeakOrdering);

    protected:
      // Internal constructor functions follow.

      // Called by the range constructor to implement [23.1.1]/9

      // _GLIBCXX_RESOLVE_LIB_DEFECTS
      // 438. Ambiguity in the "do the right thing" clause
      template<typename _Integer>
        void
        _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type)
        { _M_fill_initialize(static_cast<size_type>(__n), __x); }

      // Called by the range constructor to implement [23.1.1]/9
      template<typename _InputIterator>
        void
        _M_initialize_dispatch(_InputIterator __first, _InputIterator __last,
                   __false_type)
        {
      for (; __first != __last; ++__first)
#if __cplusplus >= 201103L
        emplace_back(*__first);
#else
        push_back(*__first);
#endif
    }

      // Called by list(n,v,a), and the range constructor when it turns out
      // to be the same thing.
      void
      _M_fill_initialize(size_type __n, const value_type& __x)
      {
    for (; __n; --__n)
      push_back(__x);
      }

#if __cplusplus >= 201103L
      // Called by list(n).
      void
      _M_default_initialize(size_type __n)
      {
    for (; __n; --__n)
      emplace_back();
      }

      // Called by resize(sz).
      void
      _M_default_append(size_type __n);
#endif

      // Internal assign functions follow.

      // Called by the range assign to implement [23.1.1]/9

      // _GLIBCXX_RESOLVE_LIB_DEFECTS
      // 438. Ambiguity in the "do the right thing" clause
      template<typename _Integer>
        void
        _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
        { _M_fill_assign(__n, __val); }

      // Called by the range assign to implement [23.1.1]/9
      template<typename _InputIterator>
        void
        _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
               __false_type);

      // Called by assign(n,t), and the range assign when it turns out
      // to be the same thing.
      void
      _M_fill_assign(size_type __n, const value_type& __val);


      // Moves the elements from [first,last) before position.
      void
      _M_transfer(iterator __position, iterator __first, iterator __last)
      { __position._M_node->_M_transfer(__first._M_node, __last._M_node); }

      // Inserts new element at position given and with value given.
#if __cplusplus < 201103L
      void
      _M_insert(iterator __position, const value_type& __x)
      {
        _Node* __tmp = _M_create_node(__x);
        __tmp->_M_hook(__position._M_node);
      }
#else
     template<typename... _Args>
       void
       _M_insert(iterator __position, _Args&&... __args)
       {
     _Node* __tmp = _M_create_node(std::forward<_Args>(__args)...);
     __tmp->_M_hook(__position._M_node);
       }
#endif

      // Erases element at position given.
      void
      _M_erase(iterator __position)
      {
        __position._M_node->_M_unhook();
        _Node* __n = static_cast<_Node*>(__position._M_node);
#if __cplusplus >= 201103L
        _M_get_Node_allocator().destroy(__n);
#else
    _M_get_Tp_allocator().destroy(std::__addressof(__n->_M_data));
#endif
        _M_put_node(__n);
      }

      // To implement the splice (and merge) bits of N1599.
      void
      _M_check_equal_allocators(list& __x)
      {
    if (std::__alloc_neq<typename _Base::_Node_alloc_type>::
        _S_do_it(_M_get_Node_allocator(), __x._M_get_Node_allocator()))
      __throw_runtime_error(__N("list::_M_check_equal_allocators"));
      }
    };

  template<typename _Tp, typename _Alloc>
    inline bool
    operator==(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
    {
      typedef typename list<_Tp, _Alloc>::const_iterator const_iterator;
      const_iterator __end1 = __x.end();
      const_iterator __end2 = __y.end();

      const_iterator __i1 = __x.begin();
      const_iterator __i2 = __y.begin();
      while (__i1 != __end1 && __i2 != __end2 && *__i1 == *__i2)
    {
      ++__i1;
      ++__i2;
    }
      return __i1 == __end1 && __i2 == __end2;
    }

  template<typename _Tp, typename _Alloc>
    inline bool
    operator<(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
    { return std::lexicographical_compare(__x.begin(), __x.end(),
                      __y.begin(), __y.end()); }

  template<typename _Tp, typename _Alloc>
    inline bool
    operator!=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
    { return !(__x == __y); }

  template<typename _Tp, typename _Alloc>
    inline bool
    operator>(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
    { return __y < __x; }

  template<typename _Tp, typename _Alloc>
    inline bool
    operator<=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
    { return !(__y < __x); }

  template<typename _Tp, typename _Alloc>
    inline bool
    operator>=(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
    { return !(__x < __y); }

  template<typename _Tp, typename _Alloc>
    inline void
    swap(list<_Tp, _Alloc>& __x, list<_Tp, _Alloc>& __y)
    { __x.swap(__y); }

_GLIBCXX_END_NAMESPACE_CONTAINER
} // namespace std

#endif /* _STL_LIST_H */