stl_vector.h

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00001 // Vector implementation -*- C++ -*-
00002 
00003 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
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) 1996
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_vector.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_VECTOR_H
00058 #define _STL_VECTOR_H 1
00059 
00060 #include <bits/stl_iterator_base_funcs.h>
00061 #include <bits/functexcept.h>
00062 #include <bits/concept_check.h>
00063 #include <initializer_list>
00064 
00065 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_D)
00066 
00067   /// See bits/stl_deque.h's _Deque_base for an explanation.
00068   template<typename _Tp, typename _Alloc>
00069     struct _Vector_base
00070     {
00071       typedef typename _Alloc::template rebind<_Tp>::other _Tp_alloc_type;
00072 
00073       struct _Vector_impl 
00074       : public _Tp_alloc_type
00075       {
00076     typename _Tp_alloc_type::pointer _M_start;
00077     typename _Tp_alloc_type::pointer _M_finish;
00078     typename _Tp_alloc_type::pointer _M_end_of_storage;
00079 
00080     _Vector_impl()
00081     : _Tp_alloc_type(), _M_start(0), _M_finish(0), _M_end_of_storage(0)
00082     { }
00083 
00084     _Vector_impl(_Tp_alloc_type const& __a)
00085     : _Tp_alloc_type(__a), _M_start(0), _M_finish(0), _M_end_of_storage(0)
00086     { }
00087       };
00088       
00089     public:
00090       typedef _Alloc allocator_type;
00091 
00092       _Tp_alloc_type&
00093       _M_get_Tp_allocator()
00094       { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); }
00095 
00096       const _Tp_alloc_type&
00097       _M_get_Tp_allocator() const
00098       { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); }
00099 
00100       allocator_type
00101       get_allocator() const
00102       { return allocator_type(_M_get_Tp_allocator()); }
00103 
00104       _Vector_base()
00105       : _M_impl() { }
00106 
00107       _Vector_base(const allocator_type& __a)
00108       : _M_impl(__a) { }
00109 
00110       _Vector_base(size_t __n, const allocator_type& __a)
00111       : _M_impl(__a)
00112       {
00113     this->_M_impl._M_start = this->_M_allocate(__n);
00114     this->_M_impl._M_finish = this->_M_impl._M_start;
00115     this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;
00116       }
00117 
00118 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00119       _Vector_base(_Vector_base&& __x)
00120       : _M_impl(__x._M_get_Tp_allocator())
00121       {
00122     this->_M_impl._M_start = __x._M_impl._M_start;
00123     this->_M_impl._M_finish = __x._M_impl._M_finish;
00124     this->_M_impl._M_end_of_storage = __x._M_impl._M_end_of_storage;
00125     __x._M_impl._M_start = 0;
00126     __x._M_impl._M_finish = 0;
00127     __x._M_impl._M_end_of_storage = 0;
00128       }
00129 #endif
00130 
00131       ~_Vector_base()
00132       { _M_deallocate(this->_M_impl._M_start, this->_M_impl._M_end_of_storage
00133               - this->_M_impl._M_start); }
00134 
00135     public:
00136       _Vector_impl _M_impl;
00137 
00138       typename _Tp_alloc_type::pointer
00139       _M_allocate(size_t __n)
00140       { return __n != 0 ? _M_impl.allocate(__n) : 0; }
00141 
00142       void
00143       _M_deallocate(typename _Tp_alloc_type::pointer __p, size_t __n)
00144       {
00145     if (__p)
00146       _M_impl.deallocate(__p, __n);
00147       }
00148     };
00149 
00150 
00151   /**
00152    *  @brief A standard container which offers fixed time access to
00153    *  individual elements in any order.
00154    *
00155    *  @ingroup sequences
00156    *
00157    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
00158    *  <a href="tables.html#66">reversible container</a>, and a
00159    *  <a href="tables.html#67">sequence</a>, including the
00160    *  <a href="tables.html#68">optional sequence requirements</a> with the
00161    *  %exception of @c push_front and @c pop_front.
00162    *
00163    *  In some terminology a %vector can be described as a dynamic
00164    *  C-style array, it offers fast and efficient access to individual
00165    *  elements in any order and saves the user from worrying about
00166    *  memory and size allocation.  Subscripting ( @c [] ) access is
00167    *  also provided as with C-style arrays.
00168   */
00169   template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
00170     class vector : protected _Vector_base<_Tp, _Alloc>
00171     {
00172       // Concept requirements.
00173       typedef typename _Alloc::value_type                _Alloc_value_type;
00174       __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
00175       __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)
00176       
00177       typedef _Vector_base<_Tp, _Alloc>          _Base;
00178       typedef typename _Base::_Tp_alloc_type         _Tp_alloc_type;
00179 
00180     public:
00181       typedef _Tp                    value_type;
00182       typedef typename _Tp_alloc_type::pointer           pointer;
00183       typedef typename _Tp_alloc_type::const_pointer     const_pointer;
00184       typedef typename _Tp_alloc_type::reference         reference;
00185       typedef typename _Tp_alloc_type::const_reference   const_reference;
00186       typedef __gnu_cxx::__normal_iterator<pointer, vector> iterator;
00187       typedef __gnu_cxx::__normal_iterator<const_pointer, vector>
00188       const_iterator;
00189       typedef std::reverse_iterator<const_iterator>  const_reverse_iterator;
00190       typedef std::reverse_iterator<iterator>        reverse_iterator;
00191       typedef size_t                     size_type;
00192       typedef ptrdiff_t                  difference_type;
00193       typedef _Alloc                                 allocator_type;
00194 
00195     protected:
00196       using _Base::_M_allocate;
00197       using _Base::_M_deallocate;
00198       using _Base::_M_impl;
00199       using _Base::_M_get_Tp_allocator;
00200 
00201     public:
00202       // [23.2.4.1] construct/copy/destroy
00203       // (assign() and get_allocator() are also listed in this section)
00204       /**
00205        *  @brief  Default constructor creates no elements.
00206        */
00207       vector()
00208       : _Base() { }
00209 
00210       /**
00211        *  @brief  Creates a %vector with no elements.
00212        *  @param  a  An allocator object.
00213        */
00214       explicit
00215       vector(const allocator_type& __a)
00216       : _Base(__a) { }
00217 
00218       /**
00219        *  @brief  Creates a %vector with copies of an exemplar element.
00220        *  @param  n  The number of elements to initially create.
00221        *  @param  value  An element to copy.
00222        *  @param  a  An allocator.
00223        *
00224        *  This constructor fills the %vector with @a n copies of @a value.
00225        */
00226       explicit
00227       vector(size_type __n, const value_type& __value = value_type(),
00228          const allocator_type& __a = allocator_type())
00229       : _Base(__n, __a)
00230       { _M_fill_initialize(__n, __value); }
00231 
00232       /**
00233        *  @brief  %Vector copy constructor.
00234        *  @param  x  A %vector of identical element and allocator types.
00235        *
00236        *  The newly-created %vector uses a copy of the allocation
00237        *  object used by @a x.  All the elements of @a x are copied,
00238        *  but any extra memory in
00239        *  @a x (for fast expansion) will not be copied.
00240        */
00241       vector(const vector& __x)
00242       : _Base(__x.size(), __x._M_get_Tp_allocator())
00243       { this->_M_impl._M_finish =
00244       std::__uninitialized_copy_a(__x.begin(), __x.end(),
00245                       this->_M_impl._M_start,
00246                       _M_get_Tp_allocator());
00247       }
00248 
00249 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00250       /**
00251        *  @brief  %Vector move constructor.
00252        *  @param  x  A %vector of identical element and allocator types.
00253        *
00254        *  The newly-created %vector contains the exact contents of @a x.
00255        *  The contents of @a x are a valid, but unspecified %vector.
00256        */
00257       vector(vector&& __x)
00258       : _Base(std::forward<_Base>(__x)) { }
00259 
00260       /**
00261        *  @brief  Builds a %vector from an initializer list.
00262        *  @param  l  An initializer_list.
00263        *  @param  a  An allocator.
00264        *
00265        *  Create a %vector consisting of copies of the elements in the
00266        *  initializer_list @a l.
00267        *
00268        *  This will call the element type's copy constructor N times
00269        *  (where N is @a l.size()) and do no memory reallocation.
00270        */
00271       vector(initializer_list<value_type> __l,
00272          const allocator_type& __a = allocator_type())
00273       : _Base(__a)
00274       {
00275     _M_range_initialize(__l.begin(), __l.end(),
00276                 random_access_iterator_tag());
00277       }
00278 #endif
00279 
00280       /**
00281        *  @brief  Builds a %vector from a range.
00282        *  @param  first  An input iterator.
00283        *  @param  last  An input iterator.
00284        *  @param  a  An allocator.
00285        *
00286        *  Create a %vector consisting of copies of the elements from
00287        *  [first,last).
00288        *
00289        *  If the iterators are forward, bidirectional, or
00290        *  random-access, then this will call the elements' copy
00291        *  constructor N times (where N is distance(first,last)) and do
00292        *  no memory reallocation.  But if only input iterators are
00293        *  used, then this will do at most 2N calls to the copy
00294        *  constructor, and logN memory reallocations.
00295        */
00296       template<typename _InputIterator>
00297         vector(_InputIterator __first, _InputIterator __last,
00298            const allocator_type& __a = allocator_type())
00299     : _Base(__a)
00300         {
00301       // Check whether it's an integral type.  If so, it's not an iterator.
00302       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
00303       _M_initialize_dispatch(__first, __last, _Integral());
00304     }
00305 
00306       /**
00307        *  The dtor only erases the elements, and note that if the
00308        *  elements themselves are pointers, the pointed-to memory is
00309        *  not touched in any way.  Managing the pointer is the user's
00310        *  responsibility.
00311        */
00312       ~vector()
00313       { std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish,
00314               _M_get_Tp_allocator()); }
00315 
00316       /**
00317        *  @brief  %Vector assignment operator.
00318        *  @param  x  A %vector of identical element and allocator types.
00319        *
00320        *  All the elements of @a x are copied, but any extra memory in
00321        *  @a x (for fast expansion) will not be copied.  Unlike the
00322        *  copy constructor, the allocator object is not copied.
00323        */
00324       vector&
00325       operator=(const vector& __x);
00326 
00327 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00328       /**
00329        *  @brief  %Vector move assignment operator.
00330        *  @param  x  A %vector of identical element and allocator types.
00331        *
00332        *  The contents of @a x are moved into this %vector (without copying).
00333        *  @a x is a valid, but unspecified %vector.
00334        */
00335       vector&
00336       operator=(vector&& __x)
00337       {
00338     // NB: DR 1204.
00339     // NB: DR 675.
00340     this->clear();
00341     this->swap(__x);
00342     return *this;
00343       }
00344 
00345       /**
00346        *  @brief  %Vector list assignment operator.
00347        *  @param  l  An initializer_list.
00348        *
00349        *  This function fills a %vector with copies of the elements in the
00350        *  initializer list @a l.
00351        *
00352        *  Note that the assignment completely changes the %vector and
00353        *  that the resulting %vector's size is the same as the number
00354        *  of elements assigned.  Old data may be lost.
00355        */
00356       vector&
00357       operator=(initializer_list<value_type> __l)
00358       {
00359     this->assign(__l.begin(), __l.end());
00360     return *this;
00361       }
00362 #endif
00363 
00364       /**
00365        *  @brief  Assigns a given value to a %vector.
00366        *  @param  n  Number of elements to be assigned.
00367        *  @param  val  Value to be assigned.
00368        *
00369        *  This function fills a %vector with @a n copies of the given
00370        *  value.  Note that the assignment completely changes the
00371        *  %vector and that the resulting %vector's size is the same as
00372        *  the number of elements assigned.  Old data may be lost.
00373        */
00374       void
00375       assign(size_type __n, const value_type& __val)
00376       { _M_fill_assign(__n, __val); }
00377 
00378       /**
00379        *  @brief  Assigns a range to a %vector.
00380        *  @param  first  An input iterator.
00381        *  @param  last   An input iterator.
00382        *
00383        *  This function fills a %vector with copies of the elements in the
00384        *  range [first,last).
00385        *
00386        *  Note that the assignment completely changes the %vector and
00387        *  that the resulting %vector's size is the same as the number
00388        *  of elements assigned.  Old data may be lost.
00389        */
00390       template<typename _InputIterator>
00391         void
00392         assign(_InputIterator __first, _InputIterator __last)
00393         {
00394       // Check whether it's an integral type.  If so, it's not an iterator.
00395       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
00396       _M_assign_dispatch(__first, __last, _Integral());
00397     }
00398 
00399 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00400       /**
00401        *  @brief  Assigns an initializer list to a %vector.
00402        *  @param  l  An initializer_list.
00403        *
00404        *  This function fills a %vector with copies of the elements in the
00405        *  initializer list @a l.
00406        *
00407        *  Note that the assignment completely changes the %vector and
00408        *  that the resulting %vector's size is the same as the number
00409        *  of elements assigned.  Old data may be lost.
00410        */
00411       void
00412       assign(initializer_list<value_type> __l)
00413       { this->assign(__l.begin(), __l.end()); }
00414 #endif
00415 
00416       /// Get a copy of the memory allocation object.
00417       using _Base::get_allocator;
00418 
00419       // iterators
00420       /**
00421        *  Returns a read/write iterator that points to the first
00422        *  element in the %vector.  Iteration is done in ordinary
00423        *  element order.
00424        */
00425       iterator
00426       begin()
00427       { return iterator(this->_M_impl._M_start); }
00428 
00429       /**
00430        *  Returns a read-only (constant) iterator that points to the
00431        *  first element in the %vector.  Iteration is done in ordinary
00432        *  element order.
00433        */
00434       const_iterator
00435       begin() const
00436       { return const_iterator(this->_M_impl._M_start); }
00437 
00438       /**
00439        *  Returns a read/write iterator that points one past the last
00440        *  element in the %vector.  Iteration is done in ordinary
00441        *  element order.
00442        */
00443       iterator
00444       end()
00445       { return iterator(this->_M_impl._M_finish); }
00446 
00447       /**
00448        *  Returns a read-only (constant) iterator that points one past
00449        *  the last element in the %vector.  Iteration is done in
00450        *  ordinary element order.
00451        */
00452       const_iterator
00453       end() const
00454       { return const_iterator(this->_M_impl._M_finish); }
00455 
00456       /**
00457        *  Returns a read/write reverse iterator that points to the
00458        *  last element in the %vector.  Iteration is done in reverse
00459        *  element order.
00460        */
00461       reverse_iterator
00462       rbegin()
00463       { return reverse_iterator(end()); }
00464 
00465       /**
00466        *  Returns a read-only (constant) reverse iterator that points
00467        *  to the last element in the %vector.  Iteration is done in
00468        *  reverse element order.
00469        */
00470       const_reverse_iterator
00471       rbegin() const
00472       { return const_reverse_iterator(end()); }
00473 
00474       /**
00475        *  Returns a read/write reverse iterator that points to one
00476        *  before the first element in the %vector.  Iteration is done
00477        *  in reverse element order.
00478        */
00479       reverse_iterator
00480       rend()
00481       { return reverse_iterator(begin()); }
00482 
00483       /**
00484        *  Returns a read-only (constant) reverse iterator that points
00485        *  to one before the first element in the %vector.  Iteration
00486        *  is done in reverse element order.
00487        */
00488       const_reverse_iterator
00489       rend() const
00490       { return const_reverse_iterator(begin()); }
00491 
00492 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00493       /**
00494        *  Returns a read-only (constant) iterator that points to the
00495        *  first element in the %vector.  Iteration is done in ordinary
00496        *  element order.
00497        */
00498       const_iterator
00499       cbegin() const
00500       { return const_iterator(this->_M_impl._M_start); }
00501 
00502       /**
00503        *  Returns a read-only (constant) iterator that points one past
00504        *  the last element in the %vector.  Iteration is done in
00505        *  ordinary element order.
00506        */
00507       const_iterator
00508       cend() const
00509       { return const_iterator(this->_M_impl._M_finish); }
00510 
00511       /**
00512        *  Returns a read-only (constant) reverse iterator that points
00513        *  to the last element in the %vector.  Iteration is done in
00514        *  reverse element order.
00515        */
00516       const_reverse_iterator
00517       crbegin() const
00518       { return const_reverse_iterator(end()); }
00519 
00520       /**
00521        *  Returns a read-only (constant) reverse iterator that points
00522        *  to one before the first element in the %vector.  Iteration
00523        *  is done in reverse element order.
00524        */
00525       const_reverse_iterator
00526       crend() const
00527       { return const_reverse_iterator(begin()); }
00528 #endif
00529 
00530       // [23.2.4.2] capacity
00531       /**  Returns the number of elements in the %vector.  */
00532       size_type
00533       size() const
00534       { return size_type(this->_M_impl._M_finish - this->_M_impl._M_start); }
00535 
00536       /**  Returns the size() of the largest possible %vector.  */
00537       size_type
00538       max_size() const
00539       { return _M_get_Tp_allocator().max_size(); }
00540 
00541       /**
00542        *  @brief  Resizes the %vector to the specified number of elements.
00543        *  @param  new_size  Number of elements the %vector should contain.
00544        *  @param  x  Data with which new elements should be populated.
00545        *
00546        *  This function will %resize the %vector to the specified
00547        *  number of elements.  If the number is smaller than the
00548        *  %vector's current size the %vector is truncated, otherwise
00549        *  the %vector is extended and new elements are populated with
00550        *  given data.
00551        */
00552       void
00553       resize(size_type __new_size, value_type __x = value_type())
00554       {
00555     if (__new_size < size())
00556       _M_erase_at_end(this->_M_impl._M_start + __new_size);
00557     else
00558       insert(end(), __new_size - size(), __x);
00559       }
00560 
00561 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00562       /**  A non-binding request to reduce capacity() to size().  */
00563       void
00564       shrink_to_fit()
00565       { std::__shrink_to_fit<vector>::_S_do_it(*this); }
00566 #endif
00567 
00568       /**
00569        *  Returns the total number of elements that the %vector can
00570        *  hold before needing to allocate more memory.
00571        */
00572       size_type
00573       capacity() const
00574       { return size_type(this->_M_impl._M_end_of_storage
00575              - this->_M_impl._M_start); }
00576 
00577       /**
00578        *  Returns true if the %vector is empty.  (Thus begin() would
00579        *  equal end().)
00580        */
00581       bool
00582       empty() const
00583       { return begin() == end(); }
00584 
00585       /**
00586        *  @brief  Attempt to preallocate enough memory for specified number of
00587        *          elements.
00588        *  @param  n  Number of elements required.
00589        *  @throw  std::length_error  If @a n exceeds @c max_size().
00590        *
00591        *  This function attempts to reserve enough memory for the
00592        *  %vector to hold the specified number of elements.  If the
00593        *  number requested is more than max_size(), length_error is
00594        *  thrown.
00595        *
00596        *  The advantage of this function is that if optimal code is a
00597        *  necessity and the user can determine the number of elements
00598        *  that will be required, the user can reserve the memory in
00599        *  %advance, and thus prevent a possible reallocation of memory
00600        *  and copying of %vector data.
00601        */
00602       void
00603       reserve(size_type __n);
00604 
00605       // element access
00606       /**
00607        *  @brief  Subscript access to the data contained in the %vector.
00608        *  @param n The index of the element for which data should be
00609        *  accessed.
00610        *  @return  Read/write reference to data.
00611        *
00612        *  This operator allows for easy, array-style, data access.
00613        *  Note that data access with this operator is unchecked and
00614        *  out_of_range lookups are not defined. (For checked lookups
00615        *  see at().)
00616        */
00617       reference
00618       operator[](size_type __n)
00619       { return *(this->_M_impl._M_start + __n); }
00620 
00621       /**
00622        *  @brief  Subscript access to the data contained in the %vector.
00623        *  @param n The index of the element for which data should be
00624        *  accessed.
00625        *  @return  Read-only (constant) reference to data.
00626        *
00627        *  This operator allows for easy, array-style, data access.
00628        *  Note that data access with this operator is unchecked and
00629        *  out_of_range lookups are not defined. (For checked lookups
00630        *  see at().)
00631        */
00632       const_reference
00633       operator[](size_type __n) const
00634       { return *(this->_M_impl._M_start + __n); }
00635 
00636     protected:
00637       /// Safety check used only from at().
00638       void
00639       _M_range_check(size_type __n) const
00640       {
00641     if (__n >= this->size())
00642       __throw_out_of_range(__N("vector::_M_range_check"));
00643       }
00644 
00645     public:
00646       /**
00647        *  @brief  Provides access to the data contained in the %vector.
00648        *  @param n The index of the element for which data should be
00649        *  accessed.
00650        *  @return  Read/write reference to data.
00651        *  @throw  std::out_of_range  If @a n is an invalid index.
00652        *
00653        *  This function provides for safer data access.  The parameter
00654        *  is first checked that it is in the range of the vector.  The
00655        *  function throws out_of_range if the check fails.
00656        */
00657       reference
00658       at(size_type __n)
00659       {
00660     _M_range_check(__n);
00661     return (*this)[__n]; 
00662       }
00663 
00664       /**
00665        *  @brief  Provides access to the data contained in the %vector.
00666        *  @param n The index of the element for which data should be
00667        *  accessed.
00668        *  @return  Read-only (constant) reference to data.
00669        *  @throw  std::out_of_range  If @a n is an invalid index.
00670        *
00671        *  This function provides for safer data access.  The parameter
00672        *  is first checked that it is in the range of the vector.  The
00673        *  function throws out_of_range if the check fails.
00674        */
00675       const_reference
00676       at(size_type __n) const
00677       {
00678     _M_range_check(__n);
00679     return (*this)[__n];
00680       }
00681 
00682       /**
00683        *  Returns a read/write reference to the data at the first
00684        *  element of the %vector.
00685        */
00686       reference
00687       front()
00688       { return *begin(); }
00689 
00690       /**
00691        *  Returns a read-only (constant) reference to the data at the first
00692        *  element of the %vector.
00693        */
00694       const_reference
00695       front() const
00696       { return *begin(); }
00697 
00698       /**
00699        *  Returns a read/write reference to the data at the last
00700        *  element of the %vector.
00701        */
00702       reference
00703       back()
00704       { return *(end() - 1); }
00705       
00706       /**
00707        *  Returns a read-only (constant) reference to the data at the
00708        *  last element of the %vector.
00709        */
00710       const_reference
00711       back() const
00712       { return *(end() - 1); }
00713 
00714       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00715       // DR 464. Suggestion for new member functions in standard containers.
00716       // data access
00717       /**
00718        *   Returns a pointer such that [data(), data() + size()) is a valid
00719        *   range.  For a non-empty %vector, data() == &front().
00720        */
00721       pointer
00722       data()
00723       { return pointer(this->_M_impl._M_start); }
00724 
00725       const_pointer
00726       data() const
00727       { return const_pointer(this->_M_impl._M_start); }
00728 
00729       // [23.2.4.3] modifiers
00730       /**
00731        *  @brief  Add data to the end of the %vector.
00732        *  @param  x  Data to be added.
00733        *
00734        *  This is a typical stack operation.  The function creates an
00735        *  element at the end of the %vector and assigns the given data
00736        *  to it.  Due to the nature of a %vector this operation can be
00737        *  done in constant time if the %vector has preallocated space
00738        *  available.
00739        */
00740       void
00741       push_back(const value_type& __x)
00742       {
00743     if (this->_M_impl._M_finish != this->_M_impl._M_end_of_storage)
00744       {
00745         this->_M_impl.construct(this->_M_impl._M_finish, __x);
00746         ++this->_M_impl._M_finish;
00747       }
00748     else
00749       _M_insert_aux(end(), __x);
00750       }
00751 
00752 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00753       void
00754       push_back(value_type&& __x)
00755       { emplace_back(std::move(__x)); }
00756 
00757       template<typename... _Args>
00758         void
00759         emplace_back(_Args&&... __args);
00760 #endif
00761 
00762       /**
00763        *  @brief  Removes last element.
00764        *
00765        *  This is a typical stack operation. It shrinks the %vector by one.
00766        *
00767        *  Note that no data is returned, and if the last element's
00768        *  data is needed, it should be retrieved before pop_back() is
00769        *  called.
00770        */
00771       void
00772       pop_back()
00773       {
00774     --this->_M_impl._M_finish;
00775     this->_M_impl.destroy(this->_M_impl._M_finish);
00776       }
00777 
00778 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00779       /**
00780        *  @brief  Inserts an object in %vector before specified iterator.
00781        *  @param  position  An iterator into the %vector.
00782        *  @param  args  Arguments.
00783        *  @return  An iterator that points to the inserted data.
00784        *
00785        *  This function will insert an object of type T constructed
00786        *  with T(std::forward<Args>(args)...) before the specified location.
00787        *  Note that this kind of operation could be expensive for a %vector
00788        *  and if it is frequently used the user should consider using
00789        *  std::list.
00790        */
00791       template<typename... _Args>
00792         iterator
00793         emplace(iterator __position, _Args&&... __args);
00794 #endif
00795 
00796       /**
00797        *  @brief  Inserts given value into %vector before specified iterator.
00798        *  @param  position  An iterator into the %vector.
00799        *  @param  x  Data to be inserted.
00800        *  @return  An iterator that points to the inserted data.
00801        *
00802        *  This function will insert a copy of the given value before
00803        *  the specified location.  Note that this kind of operation
00804        *  could be expensive for a %vector and if it is frequently
00805        *  used the user should consider using std::list.
00806        */
00807       iterator
00808       insert(iterator __position, const value_type& __x);
00809 
00810 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00811       /**
00812        *  @brief  Inserts given rvalue into %vector before specified iterator.
00813        *  @param  position  An iterator into the %vector.
00814        *  @param  x  Data to be inserted.
00815        *  @return  An iterator that points to the inserted data.
00816        *
00817        *  This function will insert a copy of the given rvalue before
00818        *  the specified location.  Note that this kind of operation
00819        *  could be expensive for a %vector and if it is frequently
00820        *  used the user should consider using std::list.
00821        */
00822       iterator
00823       insert(iterator __position, value_type&& __x)
00824       { return emplace(__position, std::move(__x)); }
00825 
00826       /**
00827        *  @brief  Inserts an initializer_list into the %vector.
00828        *  @param  position  An iterator into the %vector.
00829        *  @param  l  An initializer_list.
00830        *
00831        *  This function will insert copies of the data in the 
00832        *  initializer_list @a l into the %vector before the location
00833        *  specified by @a position.
00834        *
00835        *  Note that this kind of operation could be expensive for a
00836        *  %vector and if it is frequently used the user should
00837        *  consider using std::list.
00838        */
00839       void
00840       insert(iterator __position, initializer_list<value_type> __l)
00841       { this->insert(__position, __l.begin(), __l.end()); }
00842 #endif
00843 
00844       /**
00845        *  @brief  Inserts a number of copies of given data into the %vector.
00846        *  @param  position  An iterator into the %vector.
00847        *  @param  n  Number of elements to be inserted.
00848        *  @param  x  Data to be inserted.
00849        *
00850        *  This function will insert a specified number of copies of
00851        *  the given data before the location specified by @a position.
00852        *
00853        *  Note that this kind of operation could be expensive for a
00854        *  %vector and if it is frequently used the user should
00855        *  consider using std::list.
00856        */
00857       void
00858       insert(iterator __position, size_type __n, const value_type& __x)
00859       { _M_fill_insert(__position, __n, __x); }
00860 
00861       /**
00862        *  @brief  Inserts a range into the %vector.
00863        *  @param  position  An iterator into the %vector.
00864        *  @param  first  An input iterator.
00865        *  @param  last   An input iterator.
00866        *
00867        *  This function will insert copies of the data in the range
00868        *  [first,last) into the %vector before the location specified
00869        *  by @a pos.
00870        *
00871        *  Note that this kind of operation could be expensive for a
00872        *  %vector and if it is frequently used the user should
00873        *  consider using std::list.
00874        */
00875       template<typename _InputIterator>
00876         void
00877         insert(iterator __position, _InputIterator __first,
00878            _InputIterator __last)
00879         {
00880       // Check whether it's an integral type.  If so, it's not an iterator.
00881       typedef typename std::__is_integer<_InputIterator>::__type _Integral;
00882       _M_insert_dispatch(__position, __first, __last, _Integral());
00883     }
00884 
00885       /**
00886        *  @brief  Remove element at given position.
00887        *  @param  position  Iterator pointing to element to be erased.
00888        *  @return  An iterator pointing to the next element (or end()).
00889        *
00890        *  This function will erase the element at the given position and thus
00891        *  shorten the %vector by one.
00892        *
00893        *  Note This operation could be expensive and if it is
00894        *  frequently used the user should consider using std::list.
00895        *  The user is also cautioned that this function only erases
00896        *  the element, and that if the element is itself a pointer,
00897        *  the pointed-to memory is not touched in any way.  Managing
00898        *  the pointer is the user's responsibility.
00899        */
00900       iterator
00901       erase(iterator __position);
00902 
00903       /**
00904        *  @brief  Remove a range of elements.
00905        *  @param  first  Iterator pointing to the first element to be erased.
00906        *  @param  last  Iterator pointing to one past the last element to be
00907        *                erased.
00908        *  @return  An iterator pointing to the element pointed to by @a last
00909        *           prior to erasing (or end()).
00910        *
00911        *  This function will erase the elements in the range [first,last) and
00912        *  shorten the %vector accordingly.
00913        *
00914        *  Note This operation could be expensive and if it is
00915        *  frequently used the user should consider using std::list.
00916        *  The user is also cautioned that this function only erases
00917        *  the elements, and that if the elements themselves are
00918        *  pointers, the pointed-to memory is not touched in any way.
00919        *  Managing the pointer is the user's responsibility.
00920        */
00921       iterator
00922       erase(iterator __first, iterator __last);
00923 
00924       /**
00925        *  @brief  Swaps data with another %vector.
00926        *  @param  x  A %vector of the same element and allocator types.
00927        *
00928        *  This exchanges the elements between two vectors in constant time.
00929        *  (Three pointers, so it should be quite fast.)
00930        *  Note that the global std::swap() function is specialized such that
00931        *  std::swap(v1,v2) will feed to this function.
00932        */
00933       void
00934       swap(vector& __x)
00935       {
00936     std::swap(this->_M_impl._M_start, __x._M_impl._M_start);
00937     std::swap(this->_M_impl._M_finish, __x._M_impl._M_finish);
00938     std::swap(this->_M_impl._M_end_of_storage,
00939           __x._M_impl._M_end_of_storage);
00940 
00941     // _GLIBCXX_RESOLVE_LIB_DEFECTS
00942     // 431. Swapping containers with unequal allocators.
00943     std::__alloc_swap<_Tp_alloc_type>::_S_do_it(_M_get_Tp_allocator(),
00944                             __x._M_get_Tp_allocator());
00945       }
00946 
00947       /**
00948        *  Erases all the elements.  Note that this function only erases the
00949        *  elements, and that if the elements themselves are pointers, the
00950        *  pointed-to memory is not touched in any way.  Managing the pointer is
00951        *  the user's responsibility.
00952        */
00953       void
00954       clear()
00955       { _M_erase_at_end(this->_M_impl._M_start); }
00956 
00957     protected:
00958       /**
00959        *  Memory expansion handler.  Uses the member allocation function to
00960        *  obtain @a n bytes of memory, and then copies [first,last) into it.
00961        */
00962       template<typename _ForwardIterator>
00963         pointer
00964         _M_allocate_and_copy(size_type __n,
00965                  _ForwardIterator __first, _ForwardIterator __last)
00966         {
00967       pointer __result = this->_M_allocate(__n);
00968       __try
00969         {
00970           std::__uninitialized_copy_a(__first, __last, __result,
00971                       _M_get_Tp_allocator());
00972           return __result;
00973         }
00974       __catch(...)
00975         {
00976           _M_deallocate(__result, __n);
00977           __throw_exception_again;
00978         }
00979     }
00980 
00981 
00982       // Internal constructor functions follow.
00983 
00984       // Called by the range constructor to implement [23.1.1]/9
00985 
00986       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00987       // 438. Ambiguity in the "do the right thing" clause
00988       template<typename _Integer>
00989         void
00990         _M_initialize_dispatch(_Integer __n, _Integer __value, __true_type)
00991         {
00992       this->_M_impl._M_start = _M_allocate(static_cast<size_type>(__n));
00993       this->_M_impl._M_end_of_storage =
00994         this->_M_impl._M_start + static_cast<size_type>(__n);
00995       _M_fill_initialize(static_cast<size_type>(__n), __value);
00996     }
00997 
00998       // Called by the range constructor to implement [23.1.1]/9
00999       template<typename _InputIterator>
01000         void
01001         _M_initialize_dispatch(_InputIterator __first, _InputIterator __last,
01002                    __false_type)
01003         {
01004       typedef typename std::iterator_traits<_InputIterator>::
01005         iterator_category _IterCategory;
01006       _M_range_initialize(__first, __last, _IterCategory());
01007     }
01008 
01009       // Called by the second initialize_dispatch above
01010       template<typename _InputIterator>
01011         void
01012         _M_range_initialize(_InputIterator __first,
01013                 _InputIterator __last, std::input_iterator_tag)
01014         {
01015       for (; __first != __last; ++__first)
01016         push_back(*__first);
01017     }
01018 
01019       // Called by the second initialize_dispatch above
01020       template<typename _ForwardIterator>
01021         void
01022         _M_range_initialize(_ForwardIterator __first,
01023                 _ForwardIterator __last, std::forward_iterator_tag)
01024         {
01025       const size_type __n = std::distance(__first, __last);
01026       this->_M_impl._M_start = this->_M_allocate(__n);
01027       this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;
01028       this->_M_impl._M_finish =
01029         std::__uninitialized_copy_a(__first, __last,
01030                     this->_M_impl._M_start,
01031                     _M_get_Tp_allocator());
01032     }
01033 
01034       // Called by the first initialize_dispatch above and by the
01035       // vector(n,value,a) constructor.
01036       void
01037       _M_fill_initialize(size_type __n, const value_type& __value)
01038       {
01039     std::__uninitialized_fill_n_a(this->_M_impl._M_start, __n, __value, 
01040                       _M_get_Tp_allocator());
01041     this->_M_impl._M_finish = this->_M_impl._M_end_of_storage;
01042       }
01043 
01044 
01045       // Internal assign functions follow.  The *_aux functions do the actual
01046       // assignment work for the range versions.
01047 
01048       // Called by the range assign to implement [23.1.1]/9
01049 
01050       // _GLIBCXX_RESOLVE_LIB_DEFECTS
01051       // 438. Ambiguity in the "do the right thing" clause
01052       template<typename _Integer>
01053         void
01054         _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
01055         { _M_fill_assign(__n, __val); }
01056 
01057       // Called by the range assign to implement [23.1.1]/9
01058       template<typename _InputIterator>
01059         void
01060         _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
01061                __false_type)
01062         {
01063       typedef typename std::iterator_traits<_InputIterator>::
01064         iterator_category _IterCategory;
01065       _M_assign_aux(__first, __last, _IterCategory());
01066     }
01067 
01068       // Called by the second assign_dispatch above
01069       template<typename _InputIterator>
01070         void
01071         _M_assign_aux(_InputIterator __first, _InputIterator __last,
01072               std::input_iterator_tag);
01073 
01074       // Called by the second assign_dispatch above
01075       template<typename _ForwardIterator>
01076         void
01077         _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last,
01078               std::forward_iterator_tag);
01079 
01080       // Called by assign(n,t), and the range assign when it turns out
01081       // to be the same thing.
01082       void
01083       _M_fill_assign(size_type __n, const value_type& __val);
01084 
01085 
01086       // Internal insert functions follow.
01087 
01088       // Called by the range insert to implement [23.1.1]/9
01089 
01090       // _GLIBCXX_RESOLVE_LIB_DEFECTS
01091       // 438. Ambiguity in the "do the right thing" clause
01092       template<typename _Integer>
01093         void
01094         _M_insert_dispatch(iterator __pos, _Integer __n, _Integer __val,
01095                __true_type)
01096         { _M_fill_insert(__pos, __n, __val); }
01097 
01098       // Called by the range insert to implement [23.1.1]/9
01099       template<typename _InputIterator>
01100         void
01101         _M_insert_dispatch(iterator __pos, _InputIterator __first,
01102                _InputIterator __last, __false_type)
01103         {
01104       typedef typename std::iterator_traits<_InputIterator>::
01105         iterator_category _IterCategory;
01106       _M_range_insert(__pos, __first, __last, _IterCategory());
01107     }
01108 
01109       // Called by the second insert_dispatch above
01110       template<typename _InputIterator>
01111         void
01112         _M_range_insert(iterator __pos, _InputIterator __first,
01113             _InputIterator __last, std::input_iterator_tag);
01114 
01115       // Called by the second insert_dispatch above
01116       template<typename _ForwardIterator>
01117         void
01118         _M_range_insert(iterator __pos, _ForwardIterator __first,
01119             _ForwardIterator __last, std::forward_iterator_tag);
01120 
01121       // Called by insert(p,n,x), and the range insert when it turns out to be
01122       // the same thing.
01123       void
01124       _M_fill_insert(iterator __pos, size_type __n, const value_type& __x);
01125 
01126       // Called by insert(p,x)
01127 #ifndef __GXX_EXPERIMENTAL_CXX0X__
01128       void
01129       _M_insert_aux(iterator __position, const value_type& __x);
01130 #else
01131       template<typename... _Args>
01132         void
01133         _M_insert_aux(iterator __position, _Args&&... __args);
01134 #endif
01135 
01136       // Called by the latter.
01137       size_type
01138       _M_check_len(size_type __n, const char* __s) const
01139       {
01140     if (max_size() - size() < __n)
01141       __throw_length_error(__N(__s));
01142 
01143     const size_type __len = size() + std::max(size(), __n);
01144     return (__len < size() || __len > max_size()) ? max_size() : __len;
01145       }
01146 
01147       // Internal erase functions follow.
01148 
01149       // Called by erase(q1,q2), clear(), resize(), _M_fill_assign,
01150       // _M_assign_aux.
01151       void
01152       _M_erase_at_end(pointer __pos)
01153       {
01154     std::_Destroy(__pos, this->_M_impl._M_finish, _M_get_Tp_allocator());
01155     this->_M_impl._M_finish = __pos;
01156       }
01157     };
01158 
01159 
01160   /**
01161    *  @brief  Vector equality comparison.
01162    *  @param  x  A %vector.
01163    *  @param  y  A %vector of the same type as @a x.
01164    *  @return  True iff the size and elements of the vectors are equal.
01165    *
01166    *  This is an equivalence relation.  It is linear in the size of the
01167    *  vectors.  Vectors are considered equivalent if their sizes are equal,
01168    *  and if corresponding elements compare equal.
01169   */
01170   template<typename _Tp, typename _Alloc>
01171     inline bool
01172     operator==(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
01173     { return (__x.size() == __y.size()
01174           && std::equal(__x.begin(), __x.end(), __y.begin())); }
01175 
01176   /**
01177    *  @brief  Vector ordering relation.
01178    *  @param  x  A %vector.
01179    *  @param  y  A %vector of the same type as @a x.
01180    *  @return  True iff @a x is lexicographically less than @a y.
01181    *
01182    *  This is a total ordering relation.  It is linear in the size of the
01183    *  vectors.  The elements must be comparable with @c <.
01184    *
01185    *  See std::lexicographical_compare() for how the determination is made.
01186   */
01187   template<typename _Tp, typename _Alloc>
01188     inline bool
01189     operator<(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
01190     { return std::lexicographical_compare(__x.begin(), __x.end(),
01191                       __y.begin(), __y.end()); }
01192 
01193   /// Based on operator==
01194   template<typename _Tp, typename _Alloc>
01195     inline bool
01196     operator!=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
01197     { return !(__x == __y); }
01198 
01199   /// Based on operator<
01200   template<typename _Tp, typename _Alloc>
01201     inline bool
01202     operator>(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
01203     { return __y < __x; }
01204 
01205   /// Based on operator<
01206   template<typename _Tp, typename _Alloc>
01207     inline bool
01208     operator<=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
01209     { return !(__y < __x); }
01210 
01211   /// Based on operator<
01212   template<typename _Tp, typename _Alloc>
01213     inline bool
01214     operator>=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
01215     { return !(__x < __y); }
01216 
01217   /// See std::vector::swap().
01218   template<typename _Tp, typename _Alloc>
01219     inline void
01220     swap(vector<_Tp, _Alloc>& __x, vector<_Tp, _Alloc>& __y)
01221     { __x.swap(__y); }
01222 
01223 _GLIBCXX_END_NESTED_NAMESPACE
01224 
01225 #endif /* _STL_VECTOR_H */