stl_deque.h

Go to the documentation of this file.
00001 // Deque implementation -*- C++ -*-
00002 
00003 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
00004 // Free Software Foundation, Inc.
00005 //
00006 // This file is part of the GNU ISO C++ Library.  This library is free
00007 // software; you can redistribute it and/or modify it under the
00008 // terms of the GNU General Public License as published by the
00009 // Free Software Foundation; either version 3, or (at your option)
00010 // any later version.
00011 
00012 // This library is distributed in the hope that it will be useful,
00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00015 // GNU General Public License for more details.
00016 
00017 // Under Section 7 of GPL version 3, you are granted additional
00018 // permissions described in the GCC Runtime Library Exception, version
00019 // 3.1, as published by the Free Software Foundation.
00020 
00021 // You should have received a copy of the GNU General Public License and
00022 // a copy of the GCC Runtime Library Exception along with this program;
00023 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00024 // <http://www.gnu.org/licenses/>.
00025 
00026 /*
00027  *
00028  * Copyright (c) 1994
00029  * Hewlett-Packard Company
00030  *
00031  * Permission to use, copy, modify, distribute and sell this software
00032  * and its documentation for any purpose is hereby granted without fee,
00033  * provided that the above copyright notice appear in all copies and
00034  * that both that copyright notice and this permission notice appear
00035  * in supporting documentation.  Hewlett-Packard Company makes no
00036  * representations about the suitability of this software for any
00037  * purpose.  It is provided "as is" without express or implied warranty.
00038  *
00039  *
00040  * Copyright (c) 1997
00041  * Silicon Graphics Computer Systems, Inc.
00042  *
00043  * Permission to use, copy, modify, distribute and sell this software
00044  * and its documentation for any purpose is hereby granted without fee,
00045  * provided that the above copyright notice appear in all copies and
00046  * that both that copyright notice and this permission notice appear
00047  * in supporting documentation.  Silicon Graphics makes no
00048  * representations about the suitability of this software for any
00049  * purpose.  It is provided "as is" without express or implied warranty.
00050  */
00051 
00052 /** @file stl_deque.h
00053  *  This is an internal header file, included by other library headers.
00054  *  You should not attempt to use it directly.
00055  */
00056 
00057 #ifndef _STL_DEQUE_H
00058 #define _STL_DEQUE_H 1
00059 
00060 #include <bits/concept_check.h>
00061 #include <bits/stl_iterator_base_types.h>
00062 #include <bits/stl_iterator_base_funcs.h>
00063 #include <initializer_list>
00064 
00065 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_D)
00066 
00067   /**
00068    *  @brief This function controls the size of memory nodes.
00069    *  @param  size  The size of an element.
00070    *  @return   The number (not byte size) of elements per node.
00071    *
00072    *  This function started off as a compiler kludge from SGI, but seems to
00073    *  be a useful wrapper around a repeated constant expression.  The '512' is
00074    *  tunable (and no other code needs to change), but no investigation has
00075    *  been done since inheriting the SGI code.
00076   */
00077   inline size_t
00078   __deque_buf_size(size_t __size)
00079   { return __size < 512 ? size_t(512 / __size) : size_t(1); }
00080 
00081 
00082   /**
00083    *  @brief A deque::iterator.
00084    *
00085    *  Quite a bit of intelligence here.  Much of the functionality of
00086    *  deque is actually passed off to this class.  A deque holds two
00087    *  of these internally, marking its valid range.  Access to
00088    *  elements is done as offsets of either of those two, relying on
00089    *  operator overloading in this class.
00090    *
00091    *  All the functions are op overloads except for _M_set_node.
00092   */
00093   template<typename _Tp, typename _Ref, typename _Ptr>
00094     struct _Deque_iterator
00095     {
00096       typedef _Deque_iterator<_Tp, _Tp&, _Tp*>             iterator;
00097       typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator;
00098 
00099       static size_t _S_buffer_size()
00100       { return __deque_buf_size(sizeof(_Tp)); }
00101 
00102       typedef std::random_access_iterator_tag iterator_category;
00103       typedef _Tp                             value_type;
00104       typedef _Ptr                            pointer;
00105       typedef _Ref                            reference;
00106       typedef size_t                          size_type;
00107       typedef ptrdiff_t                       difference_type;
00108       typedef _Tp**                           _Map_pointer;
00109       typedef _Deque_iterator                 _Self;
00110 
00111       _Tp* _M_cur;
00112       _Tp* _M_first;
00113       _Tp* _M_last;
00114       _Map_pointer _M_node;
00115 
00116       _Deque_iterator(_Tp* __x, _Map_pointer __y)
00117       : _M_cur(__x), _M_first(*__y),
00118         _M_last(*__y + _S_buffer_size()), _M_node(__y) { }
00119 
00120       _Deque_iterator()
00121       : _M_cur(0), _M_first(0), _M_last(0), _M_node(0) { }
00122 
00123       _Deque_iterator(const iterator& __x)
00124       : _M_cur(__x._M_cur), _M_first(__x._M_first),
00125         _M_last(__x._M_last), _M_node(__x._M_node) { }
00126 
00127       reference
00128       operator*() const
00129       { return *_M_cur; }
00130 
00131       pointer
00132       operator->() const
00133       { return _M_cur; }
00134 
00135       _Self&
00136       operator++()
00137       {
00138     ++_M_cur;
00139     if (_M_cur == _M_last)
00140       {
00141         _M_set_node(_M_node + 1);
00142         _M_cur = _M_first;
00143       }
00144     return *this;
00145       }
00146 
00147       _Self
00148       operator++(int)
00149       {
00150     _Self __tmp = *this;
00151     ++*this;
00152     return __tmp;
00153       }
00154 
00155       _Self&
00156       operator--()
00157       {
00158     if (_M_cur == _M_first)
00159       {
00160         _M_set_node(_M_node - 1);
00161         _M_cur = _M_last;
00162       }
00163     --_M_cur;
00164     return *this;
00165       }
00166 
00167       _Self
00168       operator--(int)
00169       {
00170     _Self __tmp = *this;
00171     --*this;
00172     return __tmp;
00173       }
00174 
00175       _Self&
00176       operator+=(difference_type __n)
00177       {
00178     const difference_type __offset = __n + (_M_cur - _M_first);
00179     if (__offset >= 0 && __offset < difference_type(_S_buffer_size()))
00180       _M_cur += __n;
00181     else
00182       {
00183         const difference_type __node_offset =
00184           __offset > 0 ? __offset / difference_type(_S_buffer_size())
00185                        : -difference_type((-__offset - 1)
00186                           / _S_buffer_size()) - 1;
00187         _M_set_node(_M_node + __node_offset);
00188         _M_cur = _M_first + (__offset - __node_offset
00189                  * difference_type(_S_buffer_size()));
00190       }
00191     return *this;
00192       }
00193 
00194       _Self
00195       operator+(difference_type __n) const
00196       {
00197     _Self __tmp = *this;
00198     return __tmp += __n;
00199       }
00200 
00201       _Self&
00202       operator-=(difference_type __n)
00203       { return *this += -__n; }
00204 
00205       _Self
00206       operator-(difference_type __n) const
00207       {
00208     _Self __tmp = *this;
00209     return __tmp -= __n;
00210       }
00211 
00212       reference
00213       operator[](difference_type __n) const
00214       { return *(*this + __n); }
00215 
00216       /** 
00217        *  Prepares to traverse new_node.  Sets everything except
00218        *  _M_cur, which should therefore be set by the caller
00219        *  immediately afterwards, based on _M_first and _M_last.
00220        */
00221       void
00222       _M_set_node(_Map_pointer __new_node)
00223       {
00224     _M_node = __new_node;
00225     _M_first = *__new_node;
00226     _M_last = _M_first + difference_type(_S_buffer_size());
00227       }
00228     };
00229 
00230   // Note: we also provide overloads whose operands are of the same type in
00231   // order to avoid ambiguous overload resolution when std::rel_ops operators
00232   // are in scope (for additional details, see libstdc++/3628)
00233   template<typename _Tp, typename _Ref, typename _Ptr>
00234     inline bool
00235     operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
00236            const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
00237     { return __x._M_cur == __y._M_cur; }
00238 
00239   template<typename _Tp, typename _RefL, typename _PtrL,
00240        typename _RefR, typename _PtrR>
00241     inline bool
00242     operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
00243            const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
00244     { return __x._M_cur == __y._M_cur; }
00245 
00246   template<typename _Tp, typename _Ref, typename _Ptr>
00247     inline bool
00248     operator!=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
00249            const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
00250     { return !(__x == __y); }
00251 
00252   template<typename _Tp, typename _RefL, typename _PtrL,
00253        typename _RefR, typename _PtrR>
00254     inline bool
00255     operator!=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
00256            const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
00257     { return !(__x == __y); }
00258 
00259   template<typename _Tp, typename _Ref, typename _Ptr>
00260     inline bool
00261     operator<(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
00262           const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
00263     { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur)
00264                                           : (__x._M_node < __y._M_node); }
00265 
00266   template<typename _Tp, typename _RefL, typename _PtrL,
00267        typename _RefR, typename _PtrR>
00268     inline bool
00269     operator<(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
00270           const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
00271     { return (__x._M_node == __y._M_node) ? (__x._M_cur < __y._M_cur)
00272                                       : (__x._M_node < __y._M_node); }
00273 
00274   template<typename _Tp, typename _Ref, typename _Ptr>
00275     inline bool
00276     operator>(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
00277           const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
00278     { return __y < __x; }
00279 
00280   template<typename _Tp, typename _RefL, typename _PtrL,
00281        typename _RefR, typename _PtrR>
00282     inline bool
00283     operator>(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
00284           const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
00285     { return __y < __x; }
00286 
00287   template<typename _Tp, typename _Ref, typename _Ptr>
00288     inline bool
00289     operator<=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
00290            const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
00291     { return !(__y < __x); }
00292 
00293   template<typename _Tp, typename _RefL, typename _PtrL,
00294        typename _RefR, typename _PtrR>
00295     inline bool
00296     operator<=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
00297            const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
00298     { return !(__y < __x); }
00299 
00300   template<typename _Tp, typename _Ref, typename _Ptr>
00301     inline bool
00302     operator>=(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
00303            const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
00304     { return !(__x < __y); }
00305 
00306   template<typename _Tp, typename _RefL, typename _PtrL,
00307        typename _RefR, typename _PtrR>
00308     inline bool
00309     operator>=(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
00310            const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
00311     { return !(__x < __y); }
00312 
00313   // _GLIBCXX_RESOLVE_LIB_DEFECTS
00314   // According to the resolution of DR179 not only the various comparison
00315   // operators but also operator- must accept mixed iterator/const_iterator
00316   // parameters.
00317   template<typename _Tp, typename _Ref, typename _Ptr>
00318     inline typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type
00319     operator-(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
00320           const _Deque_iterator<_Tp, _Ref, _Ptr>& __y)
00321     {
00322       return typename _Deque_iterator<_Tp, _Ref, _Ptr>::difference_type
00323     (_Deque_iterator<_Tp, _Ref, _Ptr>::_S_buffer_size())
00324     * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first)
00325     + (__y._M_last - __y._M_cur);
00326     }
00327 
00328   template<typename _Tp, typename _RefL, typename _PtrL,
00329        typename _RefR, typename _PtrR>
00330     inline typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type
00331     operator-(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
00332           const _Deque_iterator<_Tp, _RefR, _PtrR>& __y)
00333     {
00334       return typename _Deque_iterator<_Tp, _RefL, _PtrL>::difference_type
00335     (_Deque_iterator<_Tp, _RefL, _PtrL>::_S_buffer_size())
00336     * (__x._M_node - __y._M_node - 1) + (__x._M_cur - __x._M_first)
00337     + (__y._M_last - __y._M_cur);
00338     }
00339 
00340   template<typename _Tp, typename _Ref, typename _Ptr>
00341     inline _Deque_iterator<_Tp, _Ref, _Ptr>
00342     operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Ref, _Ptr>& __x)
00343     { return __x + __n; }
00344 
00345   template<typename _Tp>
00346     void
00347     fill(const _Deque_iterator<_Tp, _Tp&, _Tp*>& __first,
00348      const _Deque_iterator<_Tp, _Tp&, _Tp*>& __last, const _Tp& __value);
00349 
00350   /**
00351    *  Deque base class.  This class provides the unified face for %deque's
00352    *  allocation.  This class's constructor and destructor allocate and
00353    *  deallocate (but do not initialize) storage.  This makes %exception
00354    *  safety easier.
00355    *
00356    *  Nothing in this class ever constructs or destroys an actual Tp element.
00357    *  (Deque handles that itself.)  Only/All memory management is performed
00358    *  here.
00359   */
00360   template<typename _Tp, typename _Alloc>
00361     class _Deque_base
00362     {
00363     public:
00364       typedef _Alloc                  allocator_type;
00365 
00366       allocator_type
00367       get_allocator() const
00368       { return allocator_type(_M_get_Tp_allocator()); }
00369 
00370       typedef _Deque_iterator<_Tp, _Tp&, _Tp*>             iterator;
00371       typedef _Deque_iterator<_Tp, const _Tp&, const _Tp*> const_iterator;
00372 
00373       _Deque_base()
00374       : _M_impl()
00375       { _M_initialize_map(0); }
00376 
00377       _Deque_base(const allocator_type& __a, size_t __num_elements)
00378       : _M_impl(__a)
00379       { _M_initialize_map(__num_elements); }
00380 
00381       _Deque_base(const allocator_type& __a)
00382       : _M_impl(__a)
00383       { }
00384 
00385 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00386       _Deque_base(_Deque_base&& __x)
00387       : _M_impl(__x._M_get_Tp_allocator())
00388       {
00389     _M_initialize_map(0);
00390     if (__x._M_impl._M_map)
00391       {
00392         std::swap(this->_M_impl._M_start, __x._M_impl._M_start);
00393         std::swap(this->_M_impl._M_finish, __x._M_impl._M_finish);
00394         std::swap(this->_M_impl._M_map, __x._M_impl._M_map);
00395         std::swap(this->_M_impl._M_map_size, __x._M_impl._M_map_size);
00396       }
00397       }
00398 #endif
00399 
00400       ~_Deque_base();
00401 
00402     protected:
00403       //This struct encapsulates the implementation of the std::deque
00404       //standard container and at the same time makes use of the EBO
00405       //for empty allocators.
00406       typedef typename _Alloc::template rebind<_Tp*>::other _Map_alloc_type;
00407 
00408       typedef typename _Alloc::template rebind<_Tp>::other  _Tp_alloc_type;
00409 
00410       struct _Deque_impl
00411       : public _Tp_alloc_type
00412       {
00413     _Tp** _M_map;
00414     size_t _M_map_size;
00415     iterator _M_start;
00416     iterator _M_finish;
00417 
00418     _Deque_impl()
00419     : _Tp_alloc_type(), _M_map(0), _M_map_size(0),
00420       _M_start(), _M_finish()
00421     { }
00422 
00423     _Deque_impl(const _Tp_alloc_type& __a)
00424     : _Tp_alloc_type(__a), _M_map(0), _M_map_size(0),
00425       _M_start(), _M_finish()
00426     { }
00427       };
00428 
00429       _Tp_alloc_type&
00430       _M_get_Tp_allocator()
00431       { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); }
00432 
00433       const _Tp_alloc_type&
00434       _M_get_Tp_allocator() const
00435       { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); }
00436 
00437       _Map_alloc_type
00438       _M_get_map_allocator() const
00439       { return _Map_alloc_type(_M_get_Tp_allocator()); }
00440 
00441       _Tp*
00442       _M_allocate_node()
00443       { 
00444     return _M_impl._Tp_alloc_type::allocate(__deque_buf_size(sizeof(_Tp)));
00445       }
00446 
00447       void
00448       _M_deallocate_node(_Tp* __p)
00449       {
00450     _M_impl._Tp_alloc_type::deallocate(__p, __deque_buf_size(sizeof(_Tp)));
00451       }
00452 
00453       _Tp**
00454       _M_allocate_map(size_t __n)
00455       { return _M_get_map_allocator().allocate(__n); }
00456 
00457       void
00458       _M_deallocate_map(_Tp** __p, size_t __n)
00459       { _M_get_map_allocator().deallocate(__p, __n); }
00460 
00461     protected:
00462       void _M_initialize_map(size_t);
00463       void _M_create_nodes(_Tp** __nstart, _Tp** __nfinish);
00464       void _M_destroy_nodes(_Tp** __nstart, _Tp** __nfinish);
00465       enum { _S_initial_map_size = 8 };
00466 
00467       _Deque_impl _M_impl;
00468     };
00469 
00470   template<typename _Tp, typename _Alloc>
00471     _Deque_base<_Tp, _Alloc>::
00472     ~_Deque_base()
00473     {
00474       if (this->_M_impl._M_map)
00475     {
00476       _M_destroy_nodes(this->_M_impl._M_start._M_node,
00477                this->_M_impl._M_finish._M_node + 1);
00478       _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
00479     }
00480     }
00481 
00482   /**
00483    *  @brief Layout storage.
00484    *  @param  num_elements  The count of T's for which to allocate space
00485    *                        at first.
00486    *  @return   Nothing.
00487    *
00488    *  The initial underlying memory layout is a bit complicated...
00489   */
00490   template<typename _Tp, typename _Alloc>
00491     void
00492     _Deque_base<_Tp, _Alloc>::
00493     _M_initialize_map(size_t __num_elements)
00494     {
00495       const size_t __num_nodes = (__num_elements/ __deque_buf_size(sizeof(_Tp))
00496                   + 1);
00497 
00498       this->_M_impl._M_map_size = std::max((size_t) _S_initial_map_size,
00499                        size_t(__num_nodes + 2));
00500       this->_M_impl._M_map = _M_allocate_map(this->_M_impl._M_map_size);
00501 
00502       // For "small" maps (needing less than _M_map_size nodes), allocation
00503       // starts in the middle elements and grows outwards.  So nstart may be
00504       // the beginning of _M_map, but for small maps it may be as far in as
00505       // _M_map+3.
00506 
00507       _Tp** __nstart = (this->_M_impl._M_map
00508             + (this->_M_impl._M_map_size - __num_nodes) / 2);
00509       _Tp** __nfinish = __nstart + __num_nodes;
00510 
00511       __try
00512     { _M_create_nodes(__nstart, __nfinish); }
00513       __catch(...)
00514     {
00515       _M_deallocate_map(this->_M_impl._M_map, this->_M_impl._M_map_size);
00516       this->_M_impl._M_map = 0;
00517       this->_M_impl._M_map_size = 0;
00518       __throw_exception_again;
00519     }
00520 
00521       this->_M_impl._M_start._M_set_node(__nstart);
00522       this->_M_impl._M_finish._M_set_node(__nfinish - 1);
00523       this->_M_impl._M_start._M_cur = _M_impl._M_start._M_first;
00524       this->_M_impl._M_finish._M_cur = (this->_M_impl._M_finish._M_first
00525                     + __num_elements
00526                     % __deque_buf_size(sizeof(_Tp)));
00527     }
00528 
00529   template<typename _Tp, typename _Alloc>
00530     void
00531     _Deque_base<_Tp, _Alloc>::
00532     _M_create_nodes(_Tp** __nstart, _Tp** __nfinish)
00533     {
00534       _Tp** __cur;
00535       __try
00536     {
00537       for (__cur = __nstart; __cur < __nfinish; ++__cur)
00538         *__cur = this->_M_allocate_node();
00539     }
00540       __catch(...)
00541     {
00542       _M_destroy_nodes(__nstart, __cur);
00543       __throw_exception_again;
00544     }
00545     }
00546 
00547   template<typename _Tp, typename _Alloc>
00548     void
00549     _Deque_base<_Tp, _Alloc>::
00550     _M_destroy_nodes(_Tp** __nstart, _Tp** __nfinish)
00551     {
00552       for (_Tp** __n = __nstart; __n < __nfinish; ++__n)
00553     _M_deallocate_node(*__n);
00554     }
00555 
00556   /**
00557    *  @brief  A standard container using fixed-size memory allocation and
00558    *  constant-time manipulation of elements at either end.
00559    *
00560    *  @ingroup sequences
00561    *
00562    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
00563    *  <a href="tables.html#66">reversible container</a>, and a
00564    *  <a href="tables.html#67">sequence</a>, including the
00565    *  <a href="tables.html#68">optional sequence requirements</a>.
00566    *
00567    *  In previous HP/SGI versions of deque, there was an extra template
00568    *  parameter so users could control the node size.  This extension turned
00569    *  out to violate the C++ standard (it can be detected using template
00570    *  template parameters), and it was removed.
00571    *
00572    *  Here's how a deque<Tp> manages memory.  Each deque has 4 members:
00573    *
00574    *  - Tp**        _M_map
00575    *  - size_t      _M_map_size
00576    *  - iterator    _M_start, _M_finish
00577    *
00578    *  map_size is at least 8.  %map is an array of map_size
00579    *  pointers-to-"nodes".  (The name %map has nothing to do with the
00580    *  std::map class, and "nodes" should not be confused with
00581    *  std::list's usage of "node".)
00582    *
00583    *  A "node" has no specific type name as such, but it is referred
00584    *  to as "node" in this file.  It is a simple array-of-Tp.  If Tp
00585    *  is very large, there will be one Tp element per node (i.e., an
00586    *  "array" of one).  For non-huge Tp's, node size is inversely
00587    *  related to Tp size: the larger the Tp, the fewer Tp's will fit
00588    *  in a node.  The goal here is to keep the total size of a node
00589    *  relatively small and constant over different Tp's, to improve
00590    *  allocator efficiency.
00591    *
00592    *  Not every pointer in the %map array will point to a node.  If
00593    *  the initial number of elements in the deque is small, the
00594    *  /middle/ %map pointers will be valid, and the ones at the edges
00595    *  will be unused.  This same situation will arise as the %map
00596    *  grows: available %map pointers, if any, will be on the ends.  As
00597    *  new nodes are created, only a subset of the %map's pointers need
00598    *  to be copied "outward".
00599    *
00600    *  Class invariants:
00601    * - For any nonsingular iterator i:
00602    *    - i.node points to a member of the %map array.  (Yes, you read that
00603    *      correctly:  i.node does not actually point to a node.)  The member of
00604    *      the %map array is what actually points to the node.
00605    *    - i.first == *(i.node)    (This points to the node (first Tp element).)
00606    *    - i.last  == i.first + node_size
00607    *    - i.cur is a pointer in the range [i.first, i.last).  NOTE:
00608    *      the implication of this is that i.cur is always a dereferenceable
00609    *      pointer, even if i is a past-the-end iterator.
00610    * - Start and Finish are always nonsingular iterators.  NOTE: this
00611    * means that an empty deque must have one node, a deque with <N
00612    * elements (where N is the node buffer size) must have one node, a
00613    * deque with N through (2N-1) elements must have two nodes, etc.
00614    * - For every node other than start.node and finish.node, every
00615    * element in the node is an initialized object.  If start.node ==
00616    * finish.node, then [start.cur, finish.cur) are initialized
00617    * objects, and the elements outside that range are uninitialized
00618    * storage.  Otherwise, [start.cur, start.last) and [finish.first,
00619    * finish.cur) are initialized objects, and [start.first, start.cur)
00620    * and [finish.cur, finish.last) are uninitialized storage.
00621    * - [%map, %map + map_size) is a valid, non-empty range.
00622    * - [start.node, finish.node] is a valid range contained within
00623    *   [%map, %map + map_size).
00624    * - A pointer in the range [%map, %map + map_size) points to an allocated
00625    *   node if and only if the pointer is in the range
00626    *   [start.node, finish.node].
00627    *
00628    *  Here's the magic:  nothing in deque is "aware" of the discontiguous
00629    *  storage!
00630    *
00631    *  The memory setup and layout occurs in the parent, _Base, and the iterator
00632    *  class is entirely responsible for "leaping" from one node to the next.
00633    *  All the implementation routines for deque itself work only through the
00634    *  start and finish iterators.  This keeps the routines simple and sane,
00635    *  and we can use other standard algorithms as well.
00636   */
00637   template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
00638     class deque : protected _Deque_base<_Tp, _Alloc>
00639     {
00640       // concept requirements
00641       typedef typename _Alloc::value_type        _Alloc_value_type;
00642       __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
00643       __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)
00644 
00645       typedef _Deque_base<_Tp, _Alloc>           _Base;
00646       typedef typename _Base::_Tp_alloc_type     _Tp_alloc_type;
00647 
00648     public:
00649       typedef _Tp                                        value_type;
00650       typedef typename _Tp_alloc_type::pointer           pointer;
00651       typedef typename _Tp_alloc_type::const_pointer     const_pointer;
00652       typedef typename _Tp_alloc_type::reference         reference;
00653       typedef typename _Tp_alloc_type::const_reference   const_reference;
00654       typedef typename _Base::iterator                   iterator;
00655       typedef typename _Base::const_iterator             const_iterator;
00656       typedef std::reverse_iterator<const_iterator>      const_reverse_iterator;
00657       typedef std::reverse_iterator<iterator>            reverse_iterator;
00658       typedef size_t                             size_type;
00659       typedef ptrdiff_t                          difference_type;
00660       typedef _Alloc                             allocator_type;
00661 
00662     protected:
00663       typedef pointer*                           _Map_pointer;
00664 
00665       static size_t _S_buffer_size()
00666       { return __deque_buf_size(sizeof(_Tp)); }
00667 
00668       // Functions controlling memory layout, and nothing else.
00669       using _Base::_M_initialize_map;
00670       using _Base::_M_create_nodes;
00671       using _Base::_M_destroy_nodes;
00672       using _Base::_M_allocate_node;
00673       using _Base::_M_deallocate_node;
00674       using _Base::_M_allocate_map;
00675       using _Base::_M_deallocate_map;
00676       using _Base::_M_get_Tp_allocator;
00677 
00678       /** 
00679        *  A total of four data members accumulated down the hierarchy.
00680        *  May be accessed via _M_impl.*
00681        */
00682       using _Base::_M_impl;
00683 
00684     public:
00685       // [23.2.1.1] construct/copy/destroy
00686       // (assign() and get_allocator() are also listed in this section)
00687       /**
00688        *  @brief  Default constructor creates no elements.
00689        */
00690       deque()
00691       : _Base() { }
00692 
00693       /**
00694        *  @brief  Creates a %deque with no elements.
00695        *  @param  a  An allocator object.
00696        */
00697       explicit
00698       deque(const allocator_type& __a)
00699       : _Base(__a, 0) { }
00700 
00701       /**
00702        *  @brief  Creates a %deque with copies of an exemplar element.
00703        *  @param  n  The number of elements to initially create.
00704        *  @param  value  An element to copy.
00705        *  @param  a  An allocator.
00706        *
00707        *  This constructor fills the %deque with @a n copies of @a value.
00708        */
00709       explicit
00710       deque(size_type __n, const value_type& __value = value_type(),
00711         const allocator_type& __a = allocator_type())
00712       : _Base(__a, __n)
00713       { _M_fill_initialize(__value); }
00714 
00715       /**
00716        *  @brief  %Deque copy constructor.
00717        *  @param  x  A %deque of identical element and allocator types.
00718        *
00719        *  The newly-created %deque uses a copy of the allocation object used
00720        *  by @a x.
00721        */
00722       deque(const deque& __x)
00723       : _Base(__x._M_get_Tp_allocator(), __x.size())
00724       { std::__uninitialized_copy_a(__x.begin(), __x.end(), 
00725                     this->_M_impl._M_start,
00726                     _M_get_Tp_allocator()); }
00727 
00728 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00729       /**
00730        *  @brief  %Deque move constructor.
00731        *  @param  x  A %deque of identical element and allocator types.
00732        *
00733        *  The newly-created %deque contains the exact contents of @a x.
00734        *  The contents of @a x are a valid, but unspecified %deque.
00735        */
00736       deque(deque&&  __x)
00737       : _Base(std::forward<_Base>(__x)) { }
00738 
00739       /**
00740        *  @brief  Builds a %deque from an initializer list.
00741        *  @param  l  An initializer_list.
00742        *  @param  a  An allocator object.
00743        *
00744        *  Create a %deque consisting of copies of the elements in the
00745        *  initializer_list @a l.
00746        *
00747        *  This will call the element type's copy constructor N times
00748        *  (where N is l.size()) and do no memory reallocation.
00749        */
00750       deque(initializer_list<value_type> __l,
00751         const allocator_type& __a = allocator_type())
00752     : _Base(__a)
00753         {
00754       _M_range_initialize(__l.begin(), __l.end(),
00755                   random_access_iterator_tag());
00756     }
00757 #endif
00758 
00759       /**
00760        *  @brief  Builds a %deque from a range.
00761        *  @param  first  An input iterator.
00762        *  @param  last  An input iterator.
00763        *  @param  a  An allocator object.
00764        *
00765        *  Create a %deque consisting of copies of the elements from [first,
00766        *  last).
00767        *
00768        *  If the iterators are forward, bidirectional, or random-access, then
00769        *  this will call the elements' copy constructor N times (where N is
00770        *  distance(first,last)) and do no memory reallocation.  But if only
00771        *  input iterators are used, then this will do at most 2N calls to the
00772        *  copy constructor, and logN memory reallocations.
00773        */
00774       template<typename _InputIterator>
00775         deque(_InputIterator __first, _InputIterator __last,
00776           const allocator_type& __a = allocator_type())
00777     : _Base(__a)
00778         {
00779       // Check whether it's an integral type.  If so, it's not an iterator.
00780       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
00781       _M_initialize_dispatch(__first, __last, _Integral());
00782     }
00783 
00784       /**
00785        *  The dtor only erases the elements, and note that if the elements
00786        *  themselves are pointers, the pointed-to memory is not touched in any
00787        *  way.  Managing the pointer is the user's responsibility.
00788        */
00789       ~deque()
00790       { _M_destroy_data(begin(), end(), _M_get_Tp_allocator()); }
00791 
00792       /**
00793        *  @brief  %Deque assignment operator.
00794        *  @param  x  A %deque of identical element and allocator types.
00795        *
00796        *  All the elements of @a x are copied, but unlike the copy constructor,
00797        *  the allocator object is not copied.
00798        */
00799       deque&
00800       operator=(const deque& __x);
00801 
00802 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00803       /**
00804        *  @brief  %Deque move assignment operator.
00805        *  @param  x  A %deque of identical element and allocator types.
00806        *
00807        *  The contents of @a x are moved into this deque (without copying).
00808        *  @a x is a valid, but unspecified %deque.
00809        */
00810       deque&
00811       operator=(deque&& __x)
00812       {
00813     // NB: DR 675.
00814     this->clear();
00815     this->swap(__x); 
00816     return *this;
00817       }
00818 
00819       /**
00820        *  @brief  Assigns an initializer list to a %deque.
00821        *  @param  l  An initializer_list.
00822        *
00823        *  This function fills a %deque with copies of the elements in the
00824        *  initializer_list @a l.
00825        *
00826        *  Note that the assignment completely changes the %deque and that the
00827        *  resulting %deque's size is the same as the number of elements
00828        *  assigned.  Old data may be lost.
00829        */
00830       deque&
00831       operator=(initializer_list<value_type> __l)
00832       {
00833     this->assign(__l.begin(), __l.end());
00834     return *this;
00835       }
00836 #endif
00837 
00838       /**
00839        *  @brief  Assigns a given value to a %deque.
00840        *  @param  n  Number of elements to be assigned.
00841        *  @param  val  Value to be assigned.
00842        *
00843        *  This function fills a %deque with @a n copies of the given
00844        *  value.  Note that the assignment completely changes the
00845        *  %deque and that the resulting %deque's size is the same as
00846        *  the number of elements assigned.  Old data may be lost.
00847        */
00848       void
00849       assign(size_type __n, const value_type& __val)
00850       { _M_fill_assign(__n, __val); }
00851 
00852       /**
00853        *  @brief  Assigns a range to a %deque.
00854        *  @param  first  An input iterator.
00855        *  @param  last   An input iterator.
00856        *
00857        *  This function fills a %deque with copies of the elements in the
00858        *  range [first,last).
00859        *
00860        *  Note that the assignment completely changes the %deque and that the
00861        *  resulting %deque's size is the same as the number of elements
00862        *  assigned.  Old data may be lost.
00863        */
00864       template<typename _InputIterator>
00865         void
00866         assign(_InputIterator __first, _InputIterator __last)
00867         {
00868       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
00869       _M_assign_dispatch(__first, __last, _Integral());
00870     }
00871 
00872 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00873       /**
00874        *  @brief  Assigns an initializer list to a %deque.
00875        *  @param  l  An initializer_list.
00876        *
00877        *  This function fills a %deque with copies of the elements in the
00878        *  initializer_list @a l.
00879        *
00880        *  Note that the assignment completely changes the %deque and that the
00881        *  resulting %deque's size is the same as the number of elements
00882        *  assigned.  Old data may be lost.
00883        */
00884       void
00885       assign(initializer_list<value_type> __l)
00886       { this->assign(__l.begin(), __l.end()); }
00887 #endif
00888 
00889       /// Get a copy of the memory allocation object.
00890       allocator_type
00891       get_allocator() const
00892       { return _Base::get_allocator(); }
00893 
00894       // iterators
00895       /**
00896        *  Returns a read/write iterator that points to the first element in the
00897        *  %deque.  Iteration is done in ordinary element order.
00898        */
00899       iterator
00900       begin()
00901       { return this->_M_impl._M_start; }
00902 
00903       /**
00904        *  Returns a read-only (constant) iterator that points to the first
00905        *  element in the %deque.  Iteration is done in ordinary element order.
00906        */
00907       const_iterator
00908       begin() const
00909       { return this->_M_impl._M_start; }
00910 
00911       /**
00912        *  Returns a read/write iterator that points one past the last
00913        *  element in the %deque.  Iteration is done in ordinary
00914        *  element order.
00915        */
00916       iterator
00917       end()
00918       { return this->_M_impl._M_finish; }
00919 
00920       /**
00921        *  Returns a read-only (constant) iterator that points one past
00922        *  the last element in the %deque.  Iteration is done in
00923        *  ordinary element order.
00924        */
00925       const_iterator
00926       end() const
00927       { return this->_M_impl._M_finish; }
00928 
00929       /**
00930        *  Returns a read/write reverse iterator that points to the
00931        *  last element in the %deque.  Iteration is done in reverse
00932        *  element order.
00933        */
00934       reverse_iterator
00935       rbegin()
00936       { return reverse_iterator(this->_M_impl._M_finish); }
00937 
00938       /**
00939        *  Returns a read-only (constant) reverse iterator that points
00940        *  to the last element in the %deque.  Iteration is done in
00941        *  reverse element order.
00942        */
00943       const_reverse_iterator
00944       rbegin() const
00945       { return const_reverse_iterator(this->_M_impl._M_finish); }
00946 
00947       /**
00948        *  Returns a read/write reverse iterator that points to one
00949        *  before the first element in the %deque.  Iteration is done
00950        *  in reverse element order.
00951        */
00952       reverse_iterator
00953       rend()
00954       { return reverse_iterator(this->_M_impl._M_start); }
00955 
00956       /**
00957        *  Returns a read-only (constant) reverse iterator that points
00958        *  to one before the first element in the %deque.  Iteration is
00959        *  done in reverse element order.
00960        */
00961       const_reverse_iterator
00962       rend() const
00963       { return const_reverse_iterator(this->_M_impl._M_start); }
00964 
00965 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00966       /**
00967        *  Returns a read-only (constant) iterator that points to the first
00968        *  element in the %deque.  Iteration is done in ordinary element order.
00969        */
00970       const_iterator
00971       cbegin() const
00972       { return this->_M_impl._M_start; }
00973 
00974       /**
00975        *  Returns a read-only (constant) iterator that points one past
00976        *  the last element in the %deque.  Iteration is done in
00977        *  ordinary element order.
00978        */
00979       const_iterator
00980       cend() const
00981       { return this->_M_impl._M_finish; }
00982 
00983       /**
00984        *  Returns a read-only (constant) reverse iterator that points
00985        *  to the last element in the %deque.  Iteration is done in
00986        *  reverse element order.
00987        */
00988       const_reverse_iterator
00989       crbegin() const
00990       { return const_reverse_iterator(this->_M_impl._M_finish); }
00991 
00992       /**
00993        *  Returns a read-only (constant) reverse iterator that points
00994        *  to one before the first element in the %deque.  Iteration is
00995        *  done in reverse element order.
00996        */
00997       const_reverse_iterator
00998       crend() const
00999       { return const_reverse_iterator(this->_M_impl._M_start); }
01000 #endif
01001 
01002       // [23.2.1.2] capacity
01003       /**  Returns the number of elements in the %deque.  */
01004       size_type
01005       size() const
01006       { return this->_M_impl._M_finish - this->_M_impl._M_start; }
01007 
01008       /**  Returns the size() of the largest possible %deque.  */
01009       size_type
01010       max_size() const
01011       { return _M_get_Tp_allocator().max_size(); }
01012 
01013       /**
01014        *  @brief  Resizes the %deque to the specified number of elements.
01015        *  @param  new_size  Number of elements the %deque should contain.
01016        *  @param  x  Data with which new elements should be populated.
01017        *
01018        *  This function will %resize the %deque to the specified
01019        *  number of elements.  If the number is smaller than the
01020        *  %deque's current size the %deque is truncated, otherwise the
01021        *  %deque is extended and new elements are populated with given
01022        *  data.
01023        */
01024       void
01025       resize(size_type __new_size, value_type __x = value_type())
01026       {
01027     const size_type __len = size();
01028     if (__new_size < __len)
01029       _M_erase_at_end(this->_M_impl._M_start + difference_type(__new_size));
01030     else
01031       insert(this->_M_impl._M_finish, __new_size - __len, __x);
01032       }
01033 
01034       /**
01035        *  Returns true if the %deque is empty.  (Thus begin() would
01036        *  equal end().)
01037        */
01038       bool
01039       empty() const
01040       { return this->_M_impl._M_finish == this->_M_impl._M_start; }
01041 
01042       // element access
01043       /**
01044        *  @brief Subscript access to the data contained in the %deque.
01045        *  @param n The index of the element for which data should be
01046        *  accessed.
01047        *  @return  Read/write reference to data.
01048        *
01049        *  This operator allows for easy, array-style, data access.
01050        *  Note that data access with this operator is unchecked and
01051        *  out_of_range lookups are not defined. (For checked lookups
01052        *  see at().)
01053        */
01054       reference
01055       operator[](size_type __n)
01056       { return this->_M_impl._M_start[difference_type(__n)]; }
01057 
01058       /**
01059        *  @brief Subscript access to the data contained in the %deque.
01060        *  @param n The index of the element for which data should be
01061        *  accessed.
01062        *  @return  Read-only (constant) reference to data.
01063        *
01064        *  This operator allows for easy, array-style, data access.
01065        *  Note that data access with this operator is unchecked and
01066        *  out_of_range lookups are not defined. (For checked lookups
01067        *  see at().)
01068        */
01069       const_reference
01070       operator[](size_type __n) const
01071       { return this->_M_impl._M_start[difference_type(__n)]; }
01072 
01073     protected:
01074       /// Safety check used only from at().
01075       void
01076       _M_range_check(size_type __n) const
01077       {
01078     if (__n >= this->size())
01079       __throw_out_of_range(__N("deque::_M_range_check"));
01080       }
01081 
01082     public:
01083       /**
01084        *  @brief  Provides access to the data contained in the %deque.
01085        *  @param n The index of the element for which data should be
01086        *  accessed.
01087        *  @return  Read/write reference to data.
01088        *  @throw  std::out_of_range  If @a n is an invalid index.
01089        *
01090        *  This function provides for safer data access.  The parameter
01091        *  is first checked that it is in the range of the deque.  The
01092        *  function throws out_of_range if the check fails.
01093        */
01094       reference
01095       at(size_type __n)
01096       {
01097     _M_range_check(__n);
01098     return (*this)[__n];
01099       }
01100 
01101       /**
01102        *  @brief  Provides access to the data contained in the %deque.
01103        *  @param n The index of the element for which data should be
01104        *  accessed.
01105        *  @return  Read-only (constant) reference to data.
01106        *  @throw  std::out_of_range  If @a n is an invalid index.
01107        *
01108        *  This function provides for safer data access.  The parameter is first
01109        *  checked that it is in the range of the deque.  The function throws
01110        *  out_of_range if the check fails.
01111        */
01112       const_reference
01113       at(size_type __n) const
01114       {
01115     _M_range_check(__n);
01116     return (*this)[__n];
01117       }
01118 
01119       /**
01120        *  Returns a read/write reference to the data at the first
01121        *  element of the %deque.
01122        */
01123       reference
01124       front()
01125       { return *begin(); }
01126 
01127       /**
01128        *  Returns a read-only (constant) reference to the data at the first
01129        *  element of the %deque.
01130        */
01131       const_reference
01132       front() const
01133       { return *begin(); }
01134 
01135       /**
01136        *  Returns a read/write reference to the data at the last element of the
01137        *  %deque.
01138        */
01139       reference
01140       back()
01141       {
01142     iterator __tmp = end();
01143     --__tmp;
01144     return *__tmp;
01145       }
01146 
01147       /**
01148        *  Returns a read-only (constant) reference to the data at the last
01149        *  element of the %deque.
01150        */
01151       const_reference
01152       back() const
01153       {
01154     const_iterator __tmp = end();
01155     --__tmp;
01156     return *__tmp;
01157       }
01158 
01159       // [23.2.1.2] modifiers
01160       /**
01161        *  @brief  Add data to the front of the %deque.
01162        *  @param  x  Data to be added.
01163        *
01164        *  This is a typical stack operation.  The function creates an
01165        *  element at the front of the %deque and assigns the given
01166        *  data to it.  Due to the nature of a %deque this operation
01167        *  can be done in constant time.
01168        */
01169       void
01170       push_front(const value_type& __x)
01171       {
01172     if (this->_M_impl._M_start._M_cur != this->_M_impl._M_start._M_first)
01173       {
01174         this->_M_impl.construct(this->_M_impl._M_start._M_cur - 1, __x);
01175         --this->_M_impl._M_start._M_cur;
01176       }
01177     else
01178       _M_push_front_aux(__x);
01179       }
01180 
01181 #ifdef __GXX_EXPERIMENTAL_CXX0X__
01182       void
01183       push_front(value_type&& __x)
01184       { emplace_front(std::move(__x)); }
01185 
01186       template<typename... _Args>
01187         void
01188         emplace_front(_Args&&... __args);
01189 #endif
01190 
01191       /**
01192        *  @brief  Add data to the end of the %deque.
01193        *  @param  x  Data to be added.
01194        *
01195        *  This is a typical stack operation.  The function creates an
01196        *  element at the end of the %deque and assigns the given data
01197        *  to it.  Due to the nature of a %deque this operation can be
01198        *  done in constant time.
01199        */
01200       void
01201       push_back(const value_type& __x)
01202       {
01203     if (this->_M_impl._M_finish._M_cur
01204         != this->_M_impl._M_finish._M_last - 1)
01205       {
01206         this->_M_impl.construct(this->_M_impl._M_finish._M_cur, __x);
01207         ++this->_M_impl._M_finish._M_cur;
01208       }
01209     else
01210       _M_push_back_aux(__x);
01211       }
01212 
01213 #ifdef __GXX_EXPERIMENTAL_CXX0X__
01214       void
01215       push_back(value_type&& __x)
01216       { emplace_back(std::move(__x)); }
01217 
01218       template<typename... _Args>
01219         void
01220         emplace_back(_Args&&... __args);
01221 #endif
01222 
01223       /**
01224        *  @brief  Removes first element.
01225        *
01226        *  This is a typical stack operation.  It shrinks the %deque by one.
01227        *
01228        *  Note that no data is returned, and if the first element's data is
01229        *  needed, it should be retrieved before pop_front() is called.
01230        */
01231       void
01232       pop_front()
01233       {
01234     if (this->_M_impl._M_start._M_cur
01235         != this->_M_impl._M_start._M_last - 1)
01236       {
01237         this->_M_impl.destroy(this->_M_impl._M_start._M_cur);
01238         ++this->_M_impl._M_start._M_cur;
01239       }
01240     else
01241       _M_pop_front_aux();
01242       }
01243 
01244       /**
01245        *  @brief  Removes last element.
01246        *
01247        *  This is a typical stack operation.  It shrinks the %deque by one.
01248        *
01249        *  Note that no data is returned, and if the last element's data is
01250        *  needed, it should be retrieved before pop_back() is called.
01251        */
01252       void
01253       pop_back()
01254       {
01255     if (this->_M_impl._M_finish._M_cur
01256         != this->_M_impl._M_finish._M_first)
01257       {
01258         --this->_M_impl._M_finish._M_cur;
01259         this->_M_impl.destroy(this->_M_impl._M_finish._M_cur);
01260       }
01261     else
01262       _M_pop_back_aux();
01263       }
01264 
01265 #ifdef __GXX_EXPERIMENTAL_CXX0X__
01266       /**
01267        *  @brief  Inserts an object in %deque before specified iterator.
01268        *  @param  position  An iterator into the %deque.
01269        *  @param  args  Arguments.
01270        *  @return  An iterator that points to the inserted data.
01271        *
01272        *  This function will insert an object of type T constructed
01273        *  with T(std::forward<Args>(args)...) before the specified location.
01274        */
01275       template<typename... _Args>
01276         iterator
01277         emplace(iterator __position, _Args&&... __args);
01278 #endif
01279 
01280       /**
01281        *  @brief  Inserts given value into %deque before specified iterator.
01282        *  @param  position  An iterator into the %deque.
01283        *  @param  x  Data to be inserted.
01284        *  @return  An iterator that points to the inserted data.
01285        *
01286        *  This function will insert a copy of the given value before the
01287        *  specified location.
01288        */
01289       iterator
01290       insert(iterator __position, const value_type& __x);
01291 
01292 #ifdef __GXX_EXPERIMENTAL_CXX0X__
01293       /**
01294        *  @brief  Inserts given rvalue into %deque before specified iterator.
01295        *  @param  position  An iterator into the %deque.
01296        *  @param  x  Data to be inserted.
01297        *  @return  An iterator that points to the inserted data.
01298        *
01299        *  This function will insert a copy of the given rvalue before the
01300        *  specified location.
01301        */
01302       iterator
01303       insert(iterator __position, value_type&& __x)
01304       { return emplace(__position, std::move(__x)); }
01305 
01306       /**
01307        *  @brief  Inserts an initializer list into the %deque.
01308        *  @param  p  An iterator into the %deque.
01309        *  @param  l  An initializer_list.
01310        *
01311        *  This function will insert copies of the data in the
01312        *  initializer_list @a l into the %deque before the location
01313        *  specified by @a p.  This is known as "list insert."
01314        */
01315       void
01316       insert(iterator __p, initializer_list<value_type> __l)
01317       { this->insert(__p, __l.begin(), __l.end()); }
01318 #endif
01319 
01320       /**
01321        *  @brief  Inserts a number of copies of given data into the %deque.
01322        *  @param  position  An iterator into the %deque.
01323        *  @param  n  Number of elements to be inserted.
01324        *  @param  x  Data to be inserted.
01325        *
01326        *  This function will insert a specified number of copies of the given
01327        *  data before the location specified by @a position.
01328        */
01329       void
01330       insert(iterator __position, size_type __n, const value_type& __x)
01331       { _M_fill_insert(__position, __n, __x); }
01332 
01333       /**
01334        *  @brief  Inserts a range into the %deque.
01335        *  @param  position  An iterator into the %deque.
01336        *  @param  first  An input iterator.
01337        *  @param  last   An input iterator.
01338        *
01339        *  This function will insert copies of the data in the range
01340        *  [first,last) into the %deque before the location specified
01341        *  by @a pos.  This is known as "range insert."
01342        */
01343       template<typename _InputIterator>
01344         void
01345         insert(iterator __position, _InputIterator __first,
01346            _InputIterator __last)
01347         {
01348       // Check whether it's an integral type.  If so, it's not an iterator.
01349       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
01350       _M_insert_dispatch(__position, __first, __last, _Integral());
01351     }
01352 
01353       /**
01354        *  @brief  Remove element at given position.
01355        *  @param  position  Iterator pointing to element to be erased.
01356        *  @return  An iterator pointing to the next element (or end()).
01357        *
01358        *  This function will erase the element at the given position and thus
01359        *  shorten the %deque by one.
01360        *
01361        *  The user is cautioned that
01362        *  this function only erases the element, and that if the element is
01363        *  itself a pointer, the pointed-to memory is not touched in any way.
01364        *  Managing the pointer is the user's responsibility.
01365        */
01366       iterator
01367       erase(iterator __position);
01368 
01369       /**
01370        *  @brief  Remove a range of elements.
01371        *  @param  first  Iterator pointing to the first element to be erased.
01372        *  @param  last  Iterator pointing to one past the last element to be
01373        *                erased.
01374        *  @return  An iterator pointing to the element pointed to by @a last
01375        *           prior to erasing (or end()).
01376        *
01377        *  This function will erase the elements in the range [first,last) and
01378        *  shorten the %deque accordingly.
01379        *
01380        *  The user is cautioned that
01381        *  this function only erases the elements, and that if the elements
01382        *  themselves are pointers, the pointed-to memory is not touched in any
01383        *  way.  Managing the pointer is the user's responsibility.
01384        */
01385       iterator
01386       erase(iterator __first, iterator __last);
01387 
01388       /**
01389        *  @brief  Swaps data with another %deque.
01390        *  @param  x  A %deque of the same element and allocator types.
01391        *
01392        *  This exchanges the elements between two deques in constant time.
01393        *  (Four pointers, so it should be quite fast.)
01394        *  Note that the global std::swap() function is specialized such that
01395        *  std::swap(d1,d2) will feed to this function.
01396        */
01397       void
01398 #ifdef __GXX_EXPERIMENTAL_CXX0X__
01399       swap(deque&& __x)
01400 #else
01401       swap(deque& __x)
01402 #endif
01403       {
01404     std::swap(this->_M_impl._M_start, __x._M_impl._M_start);
01405     std::swap(this->_M_impl._M_finish, __x._M_impl._M_finish);
01406     std::swap(this->_M_impl._M_map, __x._M_impl._M_map);
01407     std::swap(this->_M_impl._M_map_size, __x._M_impl._M_map_size);
01408 
01409     // _GLIBCXX_RESOLVE_LIB_DEFECTS
01410     // 431. Swapping containers with unequal allocators.
01411     std::__alloc_swap<_Tp_alloc_type>::_S_do_it(_M_get_Tp_allocator(),
01412                             __x._M_get_Tp_allocator());
01413       }
01414 
01415       /**
01416        *  Erases all the elements.  Note that this function only erases the
01417        *  elements, and that if the elements themselves are pointers, the
01418        *  pointed-to memory is not touched in any way.  Managing the pointer is
01419        *  the user's responsibility.
01420        */
01421       void
01422       clear()
01423       { _M_erase_at_end(begin()); }
01424 
01425     protected:
01426       // Internal constructor functions follow.
01427 
01428       // called by the range constructor to implement [23.1.1]/9
01429 
01430       // _GLIBCXX_RESOLVE_LIB_DEFECTS
01431       // 438. Ambiguity in the "do the right thing" clause
01432       template<typename _Integer>
01433         void
01434         _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type)
01435         {
01436       _M_initialize_map(static_cast<size_type>(__n));
01437       _M_fill_initialize(__x);
01438     }
01439 
01440       // called by the range constructor to implement [23.1.1]/9
01441       template<typename _InputIterator>
01442         void
01443         _M_initialize_dispatch(_InputIterator __first, _InputIterator __last,
01444                    __false_type)
01445         {
01446       typedef typename std::iterator_traits<_InputIterator>::
01447         iterator_category _IterCategory;
01448       _M_range_initialize(__first, __last, _IterCategory());
01449     }
01450 
01451       // called by the second initialize_dispatch above
01452       //@{
01453       /**
01454        *  @brief Fills the deque with whatever is in [first,last).
01455        *  @param  first  An input iterator.
01456        *  @param  last  An input iterator.
01457        *  @return   Nothing.
01458        *
01459        *  If the iterators are actually forward iterators (or better), then the
01460        *  memory layout can be done all at once.  Else we move forward using
01461        *  push_back on each value from the iterator.
01462        */
01463       template<typename _InputIterator>
01464         void
01465         _M_range_initialize(_InputIterator __first, _InputIterator __last,
01466                 std::input_iterator_tag);
01467 
01468       // called by the second initialize_dispatch above
01469       template<typename _ForwardIterator>
01470         void
01471         _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last,
01472                 std::forward_iterator_tag);
01473       //@}
01474 
01475       /**
01476        *  @brief Fills the %deque with copies of value.
01477        *  @param  value  Initial value.
01478        *  @return   Nothing.
01479        *  @pre _M_start and _M_finish have already been initialized,
01480        *  but none of the %deque's elements have yet been constructed.
01481        *
01482        *  This function is called only when the user provides an explicit size
01483        *  (with or without an explicit exemplar value).
01484        */
01485       void
01486       _M_fill_initialize(const value_type& __value);
01487 
01488       // Internal assign functions follow.  The *_aux functions do the actual
01489       // assignment work for the range versions.
01490 
01491       // called by the range assign to implement [23.1.1]/9
01492 
01493       // _GLIBCXX_RESOLVE_LIB_DEFECTS
01494       // 438. Ambiguity in the "do the right thing" clause
01495       template<typename _Integer>
01496         void
01497         _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
01498         { _M_fill_assign(__n, __val); }
01499 
01500       // called by the range assign to implement [23.1.1]/9
01501       template<typename _InputIterator>
01502         void
01503         _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
01504                __false_type)
01505         {
01506       typedef typename std::iterator_traits<_InputIterator>::
01507         iterator_category _IterCategory;
01508       _M_assign_aux(__first, __last, _IterCategory());
01509     }
01510 
01511       // called by the second assign_dispatch above
01512       template<typename _InputIterator>
01513         void
01514         _M_assign_aux(_InputIterator __first, _InputIterator __last,
01515               std::input_iterator_tag);
01516 
01517       // called by the second assign_dispatch above
01518       template<typename _ForwardIterator>
01519         void
01520         _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last,
01521               std::forward_iterator_tag)
01522         {
01523       const size_type __len = std::distance(__first, __last);
01524       if (__len > size())
01525         {
01526           _ForwardIterator __mid = __first;
01527           std::advance(__mid, size());
01528           std::copy(__first, __mid, begin());
01529           insert(end(), __mid, __last);
01530         }
01531       else
01532         _M_erase_at_end(std::copy(__first, __last, begin()));
01533     }
01534 
01535       // Called by assign(n,t), and the range assign when it turns out
01536       // to be the same thing.
01537       void
01538       _M_fill_assign(size_type __n, const value_type& __val)
01539       {
01540     if (__n > size())
01541       {
01542         std::fill(begin(), end(), __val);
01543         insert(end(), __n - size(), __val);
01544       }
01545     else
01546       {
01547         _M_erase_at_end(begin() + difference_type(__n));
01548         std::fill(begin(), end(), __val);
01549       }
01550       }
01551 
01552       //@{
01553       /// Helper functions for push_* and pop_*.
01554 #ifndef __GXX_EXPERIMENTAL_CXX0X__
01555       void _M_push_back_aux(const value_type&);
01556 
01557       void _M_push_front_aux(const value_type&);
01558 #else
01559       template<typename... _Args>
01560         void _M_push_back_aux(_Args&&... __args);
01561 
01562       template<typename... _Args>
01563         void _M_push_front_aux(_Args&&... __args);
01564 #endif
01565 
01566       void _M_pop_back_aux();
01567 
01568       void _M_pop_front_aux();
01569       //@}
01570 
01571       // Internal insert functions follow.  The *_aux functions do the actual
01572       // insertion work when all shortcuts fail.
01573 
01574       // called by the range insert to implement [23.1.1]/9
01575 
01576       // _GLIBCXX_RESOLVE_LIB_DEFECTS
01577       // 438. Ambiguity in the "do the right thing" clause
01578       template<typename _Integer>
01579         void
01580         _M_insert_dispatch(iterator __pos,
01581                _Integer __n, _Integer __x, __true_type)
01582         { _M_fill_insert(__pos, __n, __x); }
01583 
01584       // called by the range insert to implement [23.1.1]/9
01585       template<typename _InputIterator>
01586         void
01587         _M_insert_dispatch(iterator __pos,
01588                _InputIterator __first, _InputIterator __last,
01589                __false_type)
01590         {
01591       typedef typename std::iterator_traits<_InputIterator>::
01592         iterator_category _IterCategory;
01593           _M_range_insert_aux(__pos, __first, __last, _IterCategory());
01594     }
01595 
01596       // called by the second insert_dispatch above
01597       template<typename _InputIterator>
01598         void
01599         _M_range_insert_aux(iterator __pos, _InputIterator __first,
01600                 _InputIterator __last, std::input_iterator_tag);
01601 
01602       // called by the second insert_dispatch above
01603       template<typename _ForwardIterator>
01604         void
01605         _M_range_insert_aux(iterator __pos, _ForwardIterator __first,
01606                 _ForwardIterator __last, std::forward_iterator_tag);
01607 
01608       // Called by insert(p,n,x), and the range insert when it turns out to be
01609       // the same thing.  Can use fill functions in optimal situations,
01610       // otherwise passes off to insert_aux(p,n,x).
01611       void
01612       _M_fill_insert(iterator __pos, size_type __n, const value_type& __x);
01613 
01614       // called by insert(p,x)
01615 #ifndef __GXX_EXPERIMENTAL_CXX0X__
01616       iterator
01617       _M_insert_aux(iterator __pos, const value_type& __x);
01618 #else
01619       template<typename... _Args>
01620         iterator
01621         _M_insert_aux(iterator __pos, _Args&&... __args);
01622 #endif
01623 
01624       // called by insert(p,n,x) via fill_insert
01625       void
01626       _M_insert_aux(iterator __pos, size_type __n, const value_type& __x);
01627 
01628       // called by range_insert_aux for forward iterators
01629       template<typename _ForwardIterator>
01630         void
01631         _M_insert_aux(iterator __pos,
01632               _ForwardIterator __first, _ForwardIterator __last,
01633               size_type __n);
01634 
01635 
01636       // Internal erase functions follow.
01637 
01638       void
01639       _M_destroy_data_aux(iterator __first, iterator __last);
01640 
01641       // Called by ~deque().
01642       // NB: Doesn't deallocate the nodes.
01643       template<typename _Alloc1>
01644         void
01645         _M_destroy_data(iterator __first, iterator __last, const _Alloc1&)
01646         { _M_destroy_data_aux(__first, __last); }
01647 
01648       void
01649       _M_destroy_data(iterator __first, iterator __last,
01650               const std::allocator<_Tp>&)
01651       {
01652     if (!__has_trivial_destructor(value_type))
01653       _M_destroy_data_aux(__first, __last);
01654       }
01655 
01656       // Called by erase(q1, q2).
01657       void
01658       _M_erase_at_begin(iterator __pos)
01659       {
01660     _M_destroy_data(begin(), __pos, _M_get_Tp_allocator());
01661     _M_destroy_nodes(this->_M_impl._M_start._M_node, __pos._M_node);
01662     this->_M_impl._M_start = __pos;
01663       }
01664 
01665       // Called by erase(q1, q2), resize(), clear(), _M_assign_aux,
01666       // _M_fill_assign, operator=.
01667       void
01668       _M_erase_at_end(iterator __pos)
01669       {
01670     _M_destroy_data(__pos, end(), _M_get_Tp_allocator());
01671     _M_destroy_nodes(__pos._M_node + 1,
01672              this->_M_impl._M_finish._M_node + 1);
01673     this->_M_impl._M_finish = __pos;
01674       }
01675 
01676       //@{
01677       /// Memory-handling helpers for the previous internal insert functions.
01678       iterator
01679       _M_reserve_elements_at_front(size_type __n)
01680       {
01681     const size_type __vacancies = this->_M_impl._M_start._M_cur
01682                                   - this->_M_impl._M_start._M_first;
01683     if (__n > __vacancies)
01684       _M_new_elements_at_front(__n - __vacancies);
01685     return this->_M_impl._M_start - difference_type(__n);
01686       }
01687 
01688       iterator
01689       _M_reserve_elements_at_back(size_type __n)
01690       {
01691     const size_type __vacancies = (this->_M_impl._M_finish._M_last
01692                        - this->_M_impl._M_finish._M_cur) - 1;
01693     if (__n > __vacancies)
01694       _M_new_elements_at_back(__n - __vacancies);
01695     return this->_M_impl._M_finish + difference_type(__n);
01696       }
01697 
01698       void
01699       _M_new_elements_at_front(size_type __new_elements);
01700 
01701       void
01702       _M_new_elements_at_back(size_type __new_elements);
01703       //@}
01704 
01705 
01706       //@{
01707       /**
01708        *  @brief Memory-handling helpers for the major %map.
01709        *
01710        *  Makes sure the _M_map has space for new nodes.  Does not
01711        *  actually add the nodes.  Can invalidate _M_map pointers.
01712        *  (And consequently, %deque iterators.)
01713        */
01714       void
01715       _M_reserve_map_at_back(size_type __nodes_to_add = 1)
01716       {
01717     if (__nodes_to_add + 1 > this->_M_impl._M_map_size
01718         - (this->_M_impl._M_finish._M_node - this->_M_impl._M_map))
01719       _M_reallocate_map(__nodes_to_add, false);
01720       }
01721 
01722       void
01723       _M_reserve_map_at_front(size_type __nodes_to_add = 1)
01724       {
01725     if (__nodes_to_add > size_type(this->_M_impl._M_start._M_node
01726                        - this->_M_impl._M_map))
01727       _M_reallocate_map(__nodes_to_add, true);
01728       }
01729 
01730       void
01731       _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front);
01732       //@}
01733     };
01734 
01735 
01736   /**
01737    *  @brief  Deque equality comparison.
01738    *  @param  x  A %deque.
01739    *  @param  y  A %deque of the same type as @a x.
01740    *  @return  True iff the size and elements of the deques are equal.
01741    *
01742    *  This is an equivalence relation.  It is linear in the size of the
01743    *  deques.  Deques are considered equivalent if their sizes are equal,
01744    *  and if corresponding elements compare equal.
01745   */
01746   template<typename _Tp, typename _Alloc>
01747     inline bool
01748     operator==(const deque<_Tp, _Alloc>& __x,
01749                          const deque<_Tp, _Alloc>& __y)
01750     { return __x.size() == __y.size()
01751              && std::equal(__x.begin(), __x.end(), __y.begin()); }
01752 
01753   /**
01754    *  @brief  Deque ordering relation.
01755    *  @param  x  A %deque.
01756    *  @param  y  A %deque of the same type as @a x.
01757    *  @return  True iff @a x is lexicographically less than @a y.
01758    *
01759    *  This is a total ordering relation.  It is linear in the size of the
01760    *  deques.  The elements must be comparable with @c <.
01761    *
01762    *  See std::lexicographical_compare() for how the determination is made.
01763   */
01764   template<typename _Tp, typename _Alloc>
01765     inline bool
01766     operator<(const deque<_Tp, _Alloc>& __x,
01767           const deque<_Tp, _Alloc>& __y)
01768     { return std::lexicographical_compare(__x.begin(), __x.end(),
01769                       __y.begin(), __y.end()); }
01770 
01771   /// Based on operator==
01772   template<typename _Tp, typename _Alloc>
01773     inline bool
01774     operator!=(const deque<_Tp, _Alloc>& __x,
01775            const deque<_Tp, _Alloc>& __y)
01776     { return !(__x == __y); }
01777 
01778   /// Based on operator<
01779   template<typename _Tp, typename _Alloc>
01780     inline bool
01781     operator>(const deque<_Tp, _Alloc>& __x,
01782           const deque<_Tp, _Alloc>& __y)
01783     { return __y < __x; }
01784 
01785   /// Based on operator<
01786   template<typename _Tp, typename _Alloc>
01787     inline bool
01788     operator<=(const deque<_Tp, _Alloc>& __x,
01789            const deque<_Tp, _Alloc>& __y)
01790     { return !(__y < __x); }
01791 
01792   /// Based on operator<
01793   template<typename _Tp, typename _Alloc>
01794     inline bool
01795     operator>=(const deque<_Tp, _Alloc>& __x,
01796            const deque<_Tp, _Alloc>& __y)
01797     { return !(__x < __y); }
01798 
01799   /// See std::deque::swap().
01800   template<typename _Tp, typename _Alloc>
01801     inline void
01802     swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>& __y)
01803     { __x.swap(__y); }
01804 
01805 #ifdef __GXX_EXPERIMENTAL_CXX0X__
01806   template<typename _Tp, typename _Alloc>
01807     inline void
01808     swap(deque<_Tp,_Alloc>&& __x, deque<_Tp,_Alloc>& __y)
01809     { __x.swap(__y); }
01810 
01811   template<typename _Tp, typename _Alloc>
01812     inline void
01813     swap(deque<_Tp,_Alloc>& __x, deque<_Tp,_Alloc>&& __y)
01814     { __x.swap(__y); }
01815 #endif
01816 
01817 _GLIBCXX_END_NESTED_NAMESPACE
01818 
01819 #endif /* _STL_DEQUE_H */

Generated on Thu Jul 23 21:16:19 2009 for libstdc++ by  doxygen 1.5.8