void insert(iterator __pos, _InputIterator __first, _InputIterator __last,
              input_iterator_tag);

  template <class _ForwardIterator>
  void insert(iterator __pos,
              _ForwardIterator __first, _ForwardIterator __last,
              forward_iterator_tag);

#endif /* __STL_MEMBER_TEMPLATES */

  iterator _M_insert_aux(iterator __pos, const value_type& __x);
  iterator _M_insert_aux(iterator __pos);
  void _M_insert_aux(iterator __pos, size_type __n, const value_type& __x);

#ifdef __STL_MEMBER_TEMPLATES  

  template <class _ForwardIterator>
  void _M_insert_aux(iterator __pos, 
                     _ForwardIterator __first, _ForwardIterator __last,
                     size_type __n);

#else /* __STL_MEMBER_TEMPLATES */
  
  void _M_insert_aux(iterator __pos,
                     const value_type* __first, const value_type* __last,
                     size_type __n);

  void _M_insert_aux(iterator __pos, 
                     const_iterator __first, const_iterator __last,
                     size_type __n);
 
#endif /* __STL_MEMBER_TEMPLATES */

  iterator _M_reserve_elements_at_front(size_type __n) {
    size_type __vacancies = _M_start._M_cur - _M_start._M_first;
    if (__n > __vacancies) 
      _M_new_elements_at_front(__n - __vacancies);
    return _M_start - difference_type(__n);
  }

  iterator _M_reserve_elements_at_back(size_type __n) {
    size_type __vacancies = (_M_finish._M_last - _M_finish._M_cur) - 1;
    if (__n > __vacancies)
      _M_new_elements_at_back(__n - __vacancies);
    return _M_finish + difference_type(__n);
  }

  void _M_new_elements_at_front(size_type __new_elements);
  void _M_new_elements_at_back(size_type __new_elements);

protected:                      // Allocation of _M_map and nodes

  // Makes sure the _M_map has space for new nodes.  Does not actually
  //  add the nodes.  Can invalidate _M_map pointers.  (And consequently, 
  //  deque iterators.)

  void _M_reserve_map_at_back (size_type __nodes_to_add = 1) {
    if (__nodes_to_add + 1 > _M_map_size - (_M_finish._M_node - _M_map))
      _M_reallocate_map(__nodes_to_add, false);
  }

  void _M_reserve_map_at_front (size_type __nodes_to_add = 1) {
    if (__nodes_to_add > size_type(_M_start._M_node - _M_map))
      _M_reallocate_map(__nodes_to_add, true);
  }

  void _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front);
 
#ifdef __STL_NON_TYPE_TMPL_PARAM_BUG
public:
  bool operator==(const deque<_Tp,_Alloc,0>& __x) const {
    return size() == __x.size() && equal(begin(), end(), __x.begin());
  }
  bool operator!=(const deque<_Tp,_Alloc,0>& __x) const {
    return size() != __x.size() || !equal(begin(), end(), __x.begin());
  }
  bool operator<(const deque<_Tp,_Alloc,0>& __x) const {
    return lexicographical_compare(begin(), end(), __x.begin(), __x.end());
  }
  bool operator>(const deque<_Tp,_Alloc,0>& __x) const {
    return __x < *this;
  }
  bool operator<=(const deque<_Tp,_Alloc,0>& __x) const {
    return !(__x < *this);
  }
  bool operator>=(const deque<_Tp,_Alloc,0>& __x) const {
    return !(*this < __x);
  }
#endif /* __STL_NON_TYPE_TMPL_PARAM_BUG */
};

// Non-inline member functions

#ifdef __STL_MEMBER_TEMPLATES

template <class _Tp, class _Alloc, size_t __bufsize>
template <class _InputIter>
void deque<_Tp, _Alloc, __bufsize>
  ::_M_assign_aux(_InputIter __first, _InputIter __last, input_iterator_tag)
{
  iterator __cur = begin();
  for ( ; __first != __last && __cur != end(); ++__cur, ++__first)
    *__cur = *__first;
  if (__first == __last)
    erase(__cur, end());
  else
    insert(end(), __first, __last);
}

#endif /* __STL_MEMBER_TEMPLATES */

template <class _Tp, class _Alloc, size_t __bufsize>
void 
deque<_Tp, _Alloc, __bufsize>::_M_fill_insert(iterator __pos,
                                              size_type __n,
                                              const value_type& __x)
{
  if (__pos._M_cur == _M_start._M_cur) {
    iterator __new_start = _M_reserve_elements_at_front(__n);
    __STL_TRY {
      uninitialized_fill(__new_start, _M_start, __x);
      _M_start = __new_start;
    }
    __STL_UNWIND(_M_destroy_nodes(__new_start._M_node, _M_start._M_node));
  }
  else if (__pos._M_cur == _M_finish._M_cur) {
    iterator __new_finish = _M_reserve_elements_at_back(__n);
    __STL_TRY {
      uninitialized_fill(_M_finish, __new_finish, __x);
      _M_finish = __new_finish;
    }
    __STL_UNWIND(_M_destroy_nodes(_M_finish._M_node + 1, 
                                  __new_finish._M_node + 1));    
  }
  else 
    _M_insert_aux(__pos, __n, __x);
}

#ifndef __STL_MEMBER_TEMPLATES  

template <class _Tp, class _Alloc, size_t __bufsize>
void deque<_Tp, _Alloc, __bufsize>::insert(iterator __pos,
                                           const value_type* __first,
                                           const value_type* __last) {
  size_type __n = __last - __first;
  if (__pos._M_cur == _M_start._M_cur) {
    iterator __new_start = _M_reserve_elements_at_front(__n);
    __STL_TRY {
      uninitialized_copy(__first, __last, __new_start);
      _M_start = __new_start;
    }
    __STL_UNWIND(_M_destroy_nodes(__new_start._M_node, _M_start._M_node));
  }
  else if (__pos._M_cur == _M_finish._M_cur) {
    iterator __new_finish = _M_reserve_elements_at_back(__n);
    __STL_TRY {
      uninitialized_copy(__first, __last, _M_finish);
      _M_finish = __new_finish;
    }
    __STL_UNWIND(_M_destroy_nodes(_M_finish._M_node + 1, 
                                  __new_finish._M_node + 1));
  }
  else
    _M_insert_aux(__pos, __first, __last, __n);
}

template <class _Tp, class _Alloc, size_t __bufsize>
void deque<_Tp,_Alloc,__bufsize>::insert(iterator __pos,
                                         const_iterator __first,
                                         const_iterator __last)
{
  size_type __n = __last - __first;
  if (__pos._M_cur == _M_start._M_cur) {
    iterator __new_start = _M_reserve_elements_at_front(__n);
    __STL_TRY {
      uninitialized_copy(__first, __last, __new_start);
      _M_start = __new_start;
    }
    __STL_UNWIND(_M_destroy_nodes(__new_start._M_node, _M_start._M_node));
  }
  else if (__pos._M_cur == _M_finish._M_cur) {
    iterator __new_finish = _M_reserve_elements_at_back(__n);
    __STL_TRY {
      uninitialized_copy(__first, __last, _M_finish);
      _M_finish = __new_finish;
    }
    __STL_UNWIND(_M_destroy_nodes(_M_finish._M_node + 1, 
                 __new_finish._M_node + 1));
  }
  else
    _M_insert_aux(__pos, __first, __last, __n);
}

#endif /* __STL_MEMBER_TEMPLATES */

template <class _Tp, class _Alloc, size_t __bufsize>
deque<_Tp,_Alloc,__bufsize>::iterator 
deque<_Tp,_Alloc,__bufsize>::erase(iterator __first, iterator __last)
{
  if (__first == _M_start && __last == _M_finish) {
    clear();
    return _M_finish;
  }
  else {
    difference_type __n = __last - __first;
    difference_type __elems_before = __first - _M_start;
    if (__elems_before < (size() - __n) / 2) {
      copy_backward(_M_start, __first, __last);
      iterator __new_start = _M_start + __n;
      destroy(_M_start, __new_start);
      _M_destroy_nodes(__new_start._M_node, _M_start._M_node);
      _M_start = __new_start;
    }
    else {
      copy(__last, _M_finish, __first);
      iterator __new_finish = _M_finish - __n;
      destroy(__new_finish, _M_finish);
      _M_destroy_nodes(__new_finish._M_node + 1, _M_finish._M_node + 1);
      _M_finish = __new_finish;
    }
    return _M_start + __elems_before;
  }
}

template <class _Tp, class _Alloc, size_t __bufsize>
void deque<_Tp,_Alloc,__bufsize>::clear()
{
  for (_Map_pointer __node = _M_start._M_node + 1;
       __node < _M_finish._M_node;
       ++__node) {
    destroy(*__node, *__node + _S_buffer_size());
    _M_deallocate_node(*__node);
  }

  if (_M_start._M_node != _M_finish._M_node) {
    destroy(_M_start._M_cur, _M_start._M_last);
    destroy(_M_finish._M_first, _M_finish._M_cur);
    _M_deallocate_node(_M_finish._M_first);
  }
  else
    destroy(_M_start._M_cur, _M_finish._M_cur);

  _M_finish = _M_start;
}

// Precondition: _M_start and _M_finish have already been initialized,
// but none of the deque's elements have yet been constructed.
template <class _Tp, class _Alloc, size_t __bufsize>
void 
deque<_Tp,_Alloc,__bufsize>::_M_fill_initialize(const value_type& __value) {
  _Map_pointer __cur;
  __STL_TRY {
    for (__cur = _M_start._M_node; __cur < _M_finish._M_node; ++__cur)
      uninitialized_fill(*__cur, *__cur + _S_buffer_size(), __value);
    uninitialized_fill(_M_finish._M_first, _M_finish._M_cur, __value);
  }
  __STL_UNWIND(destroy(_M_start, iterator(*__cur, __cur)));
}

#ifdef __STL_MEMBER_TEMPLATES  

template <class _Tp, class _Alloc, size_t __bufsize>
template <class _InputIterator>
void
deque<_Tp,_Alloc,__bufsize>::_M_range_initialize(_InputIterator __first,
                                                 _InputIterator __last,
                                                 input_iterator_tag)
{
  _M_initialize_map(0);
  __STL_TRY {
    for ( ; __first != __last; ++__first)
      push_back(*__first);
  }
  __STL_UNWIND(clear());
}

template <class _Tp, class _Alloc, size_t __bufsize>
template <class _ForwardIterator>
void
deque<_Tp,_Alloc,__bufsize>::_M_range_initialize(_ForwardIterator __first,
                                                 _ForwardIterator __last,
                                                 forward_iterator_tag)
{
  size_type __n = 0;
  distance(__first, __last, __n);
  _M_initialize_map(__n);

  _Map_pointer __cur_node;
  __STL_TRY {
    for (__cur_node = _M_start._M_node; 
         __cur_node < _M_finish._M_node; 
	 ++__cur_node) {
      _ForwardIterator __mid = __first;
      advance(__mid, _S_buffer_size());
      uninitialized_copy(__first, __mid, *__cur_node);
      __first = __mid;
    }
    uninitialized_copy(__first, __last, _M_finish._M_first);
  }
  __STL_UNWIND(destroy(_M_start, iterator(*__cur_node, __cur_node)));
}

#endif /* __STL_MEMBER_TEMPLATES */

// Called only if _M_finish._M_cur == _M_finish._M_last - 1.
template <class _Tp, class _Alloc, size_t __bufsize>
void
deque<_Tp,_Alloc,__bufsize>::_M_push_back_aux(const value_type& __t)
{
  value_type __t_copy = __t;
  _M_reserve_map_at_back();
  *(_M_finish._M_node + 1) = _M_allocate_node();
  __STL_TRY {
    construct(_M_finish._M_cur, __t_copy);
    _M_finish._M_set_node(_M_finish._M_node + 1);
    _M_finish._M_cur = _M_finish._M_first;
  }
  __STL_UNWIND(_M_deallocate_node(*(_M_finish._M_node + 1)));
}

// Called only if _M_finish._M_cur == _M_finish._M_last - 1.
template <class _Tp, class _Alloc, size_t __bufsize>
void
deque<_Tp,_Alloc,__bufsize>::_M_push_back_aux()
{
  _M_reserve_map_at_back();
  *(_M_finish._M_node + 1) = _M_allocate_node();
  __STL_TRY {
    construct(_M_finish._M_cur);
    _M_finish._M_set_node(_M_finish._M_node + 1);
    _M_finish._M_cur = _M_finish._M_first;
  }
  __STL_UNWIND(_M_deallocate_node(*(_M_finish._M_node + 1)));
}

// Called only if _M_start._M_cur == _M_start._M_first.
template <class _Tp, class _Alloc, size_t __bufsize>
void 
deque<_Tp,_Alloc,__bufsize>::_M_push_front_aux(const value_type& __t)
{
  value_type __t_copy = __t;
  _M_reserve_map_at_front();
  *(_M_start._M_node - 1) = _M_allocate_node();
  __STL_TRY {
    _M_start._M_set_node(_M_start._M_node - 1);
    _M_start._M_cur = _M_start._M_last - 1;
    construct(_M_start._M_cur, __t_copy);
  }
  __STL_UNWIND((++_M_start, _M_deallocate_node(*(_M_start._M_node - 1))));
} 

// Called only if _M_start._M_cur == _M_start._M_first.
template <class _Tp, class _Alloc, size_t __bufsize>
void 
deque<_Tp,_Alloc,__bufsize>::_M_push_front_aux()
{
  _M_reserve_map_at_front();
  *(_M_start._M_node - 1) = _M_allocate_node();
  __STL_TRY {
    _M_start._M_set_node(_M_start._M_node - 1);
    _M_start._M_cur = _M_start._M_last - 1;
    construct(_M_start._M_cur);
  }
  __STL_UNWIND((++_M_start, _M_deallocate_node(*(_M_start._M_node - 1))));
} 

// Called only if _M_finish._M_cur == _M_finish._M_first.
template <class _Tp, class _Alloc, size_t __bufsize>
void 
deque<_Tp,_Alloc,__bufsize>::_M_pop_back_aux()
{
  _M_deallocate_node(_M_finish._M_first);
  _M_finish._M_set_node(_M_finish._M_node - 1);
  _M_finish._M_cur = _M_finish._M_last - 1;
  destroy(_M_finish._M_cur);
}

// Called only if _M_start._M_cur == _M_start._M_last - 1.  Note that 
// if the deque has at least one element (a precondition for this member 
// function), and if _M_start._M_cur == _M_start._M_last, then the deque 
// must have at least two nodes.
template <class _Tp, class _Alloc, size_t __bufsize>
void 
deque<_Tp,_Alloc,__bufsize>::_M_pop_front_aux()
{
  destroy(_M_start._M_cur);
  _M_deallocate_node(_M_start._M_first);
  _M_start._M_set_node(_M_start._M_node + 1);
  _M_start._M_cur = _M_start._M_first;
}      

#ifdef __STL_MEMBER_TEMPLATES  

template <class _Tp, class _Alloc, size_t __bufsize>
template <class _InputIterator>
void 
deque<_Tp,_Alloc,__bufsize>::insert(iterator __pos,
                                    _InputIterator __first,
                                    _InputIterator __last,
                                    input_iterator_tag)
{
  copy(__first, __last, inserter(*this, __pos));
}

template <class _Tp, class _Alloc, size_t __bufsize>
template <class _ForwardIterator>
void 
deque<_Tp,_Alloc,__bufsize>::insert(iterator __pos,
                                    _ForwardIterator __first,
                                    _ForwardIterator __last,
                                    forward_iterator_tag) {
  size_type __n = 0;
  distance(__first, __last, __n);
  if (__pos._M_cur == _M_start._M_cur) {
    iterator __new_start = _M_reserve_elements_at_front(__n);
    __STL_TRY {
      uninitialized_copy(__first, __last, __new_start);
      _M_start = __new_start;
    }
    __STL_UNWIND(_M_destroy_nodes(__new_start._M_node, _M_start._M_node));
  }
  else if (__pos._M_cur == _M_finish._M_cur) {
    iterator __new_finish = _M_reserve_elements_at_back(__n);
    __STL_TRY {
      uninitialized_copy(__first, __last, _M_finish);
      _M_finish = __new_finish;
    }
    __STL_UNWIND(_M_destroy_nodes(_M_finish._M_node + 1, 
                                  __new_finish._M_node + 1));
  }
  else
    _M_insert_aux(__pos, __first, __last, __n);
}

#endif /* __STL_MEMBER_TEMPLATES */

template <class _Tp, class _Alloc, size_t __bufsize>
typename deque<_Tp, _Alloc, __bufsize>::iterator
deque<_Tp,_Alloc,__bufsize>::_M_insert_aux(iterator __pos,
                                           const value_type& __x)
{
  difference_type __index = __pos - _M_start;
  value_type __x_copy = __x;