libstdc++
stl_map.h
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00001 // Map implementation -*- C++ -*-
00002 
00003 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
00004 // 2011 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) 1996,1997
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 bits/stl_map.h
00053  *  This is an internal header file, included by other library headers.
00054  *  Do not attempt to use it directly. @headername{map}
00055  */
00056 
00057 #ifndef _STL_MAP_H
00058 #define _STL_MAP_H 1
00059 
00060 #include <bits/functexcept.h>
00061 #include <bits/concept_check.h>
00062 #include <initializer_list>
00063 
00064 namespace std _GLIBCXX_VISIBILITY(default)
00065 {
00066 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
00067 
00068   /**
00069    *  @brief A standard container made up of (key,value) pairs, which can be
00070    *  retrieved based on a key, in logarithmic time.
00071    *
00072    *  @ingroup associative_containers
00073    *
00074    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
00075    *  <a href="tables.html#66">reversible container</a>, and an
00076    *  <a href="tables.html#69">associative container</a> (using unique keys).
00077    *  For a @c map<Key,T> the key_type is Key, the mapped_type is T, and the
00078    *  value_type is std::pair<const Key,T>.
00079    *
00080    *  Maps support bidirectional iterators.
00081    *
00082    *  The private tree data is declared exactly the same way for map and
00083    *  multimap; the distinction is made entirely in how the tree functions are
00084    *  called (*_unique versus *_equal, same as the standard).
00085   */
00086   template <typename _Key, typename _Tp, typename _Compare = std::less<_Key>,
00087             typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
00088     class map
00089     {
00090     public:
00091       typedef _Key                                          key_type;
00092       typedef _Tp                                           mapped_type;
00093       typedef std::pair<const _Key, _Tp>                    value_type;
00094       typedef _Compare                                      key_compare;
00095       typedef _Alloc                                        allocator_type;
00096 
00097     private:
00098       // concept requirements
00099       typedef typename _Alloc::value_type                   _Alloc_value_type;
00100       __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
00101       __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
00102                 _BinaryFunctionConcept)
00103       __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
00104 
00105     public:
00106       class value_compare
00107       : public std::binary_function<value_type, value_type, bool>
00108       {
00109     friend class map<_Key, _Tp, _Compare, _Alloc>;
00110       protected:
00111     _Compare comp;
00112 
00113     value_compare(_Compare __c)
00114     : comp(__c) { }
00115 
00116       public:
00117     bool operator()(const value_type& __x, const value_type& __y) const
00118     { return comp(__x.first, __y.first); }
00119       };
00120 
00121     private:
00122       /// This turns a red-black tree into a [multi]map. 
00123       typedef typename _Alloc::template rebind<value_type>::other 
00124         _Pair_alloc_type;
00125 
00126       typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
00127                key_compare, _Pair_alloc_type> _Rep_type;
00128 
00129       /// The actual tree structure.
00130       _Rep_type _M_t;
00131 
00132     public:
00133       // many of these are specified differently in ISO, but the following are
00134       // "functionally equivalent"
00135       typedef typename _Pair_alloc_type::pointer         pointer;
00136       typedef typename _Pair_alloc_type::const_pointer   const_pointer;
00137       typedef typename _Pair_alloc_type::reference       reference;
00138       typedef typename _Pair_alloc_type::const_reference const_reference;
00139       typedef typename _Rep_type::iterator               iterator;
00140       typedef typename _Rep_type::const_iterator         const_iterator;
00141       typedef typename _Rep_type::size_type              size_type;
00142       typedef typename _Rep_type::difference_type        difference_type;
00143       typedef typename _Rep_type::reverse_iterator       reverse_iterator;
00144       typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
00145 
00146       // [23.3.1.1] construct/copy/destroy
00147       // (get_allocator() is normally listed in this section, but seems to have
00148       // been accidentally omitted in the printed standard)
00149       /**
00150        *  @brief  Default constructor creates no elements.
00151        */
00152       map()
00153       : _M_t() { }
00154 
00155       /**
00156        *  @brief  Creates a %map with no elements.
00157        *  @param  comp  A comparison object.
00158        *  @param  a  An allocator object.
00159        */
00160       explicit
00161       map(const _Compare& __comp,
00162       const allocator_type& __a = allocator_type())
00163       : _M_t(__comp, __a) { }
00164 
00165       /**
00166        *  @brief  %Map copy constructor.
00167        *  @param  x  A %map of identical element and allocator types.
00168        *
00169        *  The newly-created %map uses a copy of the allocation object
00170        *  used by @a x.
00171        */
00172       map(const map& __x)
00173       : _M_t(__x._M_t) { }
00174 
00175 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00176       /**
00177        *  @brief  %Map move constructor.
00178        *  @param  x  A %map of identical element and allocator types.
00179        *
00180        *  The newly-created %map contains the exact contents of @a x.
00181        *  The contents of @a x are a valid, but unspecified %map.
00182        */
00183       map(map&& __x)
00184       : _M_t(std::move(__x._M_t)) { }
00185 
00186       /**
00187        *  @brief  Builds a %map from an initializer_list.
00188        *  @param  l  An initializer_list.
00189        *  @param  comp  A comparison object.
00190        *  @param  a  An allocator object.
00191        *
00192        *  Create a %map consisting of copies of the elements in the
00193        *  initializer_list @a l.
00194        *  This is linear in N if the range is already sorted, and NlogN
00195        *  otherwise (where N is @a l.size()).
00196        */
00197       map(initializer_list<value_type> __l,
00198       const _Compare& __c = _Compare(),
00199       const allocator_type& __a = allocator_type())
00200       : _M_t(__c, __a)
00201       { _M_t._M_insert_unique(__l.begin(), __l.end()); }
00202 #endif
00203 
00204       /**
00205        *  @brief  Builds a %map from a range.
00206        *  @param  first  An input iterator.
00207        *  @param  last  An input iterator.
00208        *
00209        *  Create a %map consisting of copies of the elements from [first,last).
00210        *  This is linear in N if the range is already sorted, and NlogN
00211        *  otherwise (where N is distance(first,last)).
00212        */
00213       template<typename _InputIterator>
00214         map(_InputIterator __first, _InputIterator __last)
00215     : _M_t()
00216         { _M_t._M_insert_unique(__first, __last); }
00217 
00218       /**
00219        *  @brief  Builds a %map from a range.
00220        *  @param  first  An input iterator.
00221        *  @param  last  An input iterator.
00222        *  @param  comp  A comparison functor.
00223        *  @param  a  An allocator object.
00224        *
00225        *  Create a %map consisting of copies of the elements from [first,last).
00226        *  This is linear in N if the range is already sorted, and NlogN
00227        *  otherwise (where N is distance(first,last)).
00228        */
00229       template<typename _InputIterator>
00230         map(_InputIterator __first, _InputIterator __last,
00231         const _Compare& __comp,
00232         const allocator_type& __a = allocator_type())
00233     : _M_t(__comp, __a)
00234         { _M_t._M_insert_unique(__first, __last); }
00235 
00236       // FIXME There is no dtor declared, but we should have something
00237       // generated by Doxygen.  I don't know what tags to add to this
00238       // paragraph to make that happen:
00239       /**
00240        *  The dtor only erases the elements, and note that if the elements
00241        *  themselves are pointers, the pointed-to memory is not touched in any
00242        *  way.  Managing the pointer is the user's responsibility.
00243        */
00244 
00245       /**
00246        *  @brief  %Map assignment operator.
00247        *  @param  x  A %map of identical element and allocator types.
00248        *
00249        *  All the elements of @a x are copied, but unlike the copy constructor,
00250        *  the allocator object is not copied.
00251        */
00252       map&
00253       operator=(const map& __x)
00254       {
00255     _M_t = __x._M_t;
00256     return *this;
00257       }
00258 
00259 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00260       /**
00261        *  @brief  %Map move assignment operator.
00262        *  @param  x  A %map of identical element and allocator types.
00263        *
00264        *  The contents of @a x are moved into this map (without copying).
00265        *  @a x is a valid, but unspecified %map.
00266        */
00267       map&
00268       operator=(map&& __x)
00269       {
00270     // NB: DR 1204.
00271     // NB: DR 675.
00272     this->clear();
00273     this->swap(__x);
00274     return *this;
00275       }
00276 
00277       /**
00278        *  @brief  %Map list assignment operator.
00279        *  @param  l  An initializer_list.
00280        *
00281        *  This function fills a %map with copies of the elements in the
00282        *  initializer list @a l.
00283        *
00284        *  Note that the assignment completely changes the %map and
00285        *  that the resulting %map's size is the same as the number
00286        *  of elements assigned.  Old data may be lost.
00287        */
00288       map&
00289       operator=(initializer_list<value_type> __l)
00290       {
00291     this->clear();
00292     this->insert(__l.begin(), __l.end());
00293     return *this;
00294       }
00295 #endif
00296 
00297       /// Get a copy of the memory allocation object.
00298       allocator_type
00299       get_allocator() const
00300       { return _M_t.get_allocator(); }
00301 
00302       // iterators
00303       /**
00304        *  Returns a read/write iterator that points to the first pair in the
00305        *  %map.
00306        *  Iteration is done in ascending order according to the keys.
00307        */
00308       iterator
00309       begin()
00310       { return _M_t.begin(); }
00311 
00312       /**
00313        *  Returns a read-only (constant) iterator that points to the first pair
00314        *  in the %map.  Iteration is done in ascending order according to the
00315        *  keys.
00316        */
00317       const_iterator
00318       begin() const
00319       { return _M_t.begin(); }
00320 
00321       /**
00322        *  Returns a read/write iterator that points one past the last
00323        *  pair in the %map.  Iteration is done in ascending order
00324        *  according to the keys.
00325        */
00326       iterator
00327       end()
00328       { return _M_t.end(); }
00329 
00330       /**
00331        *  Returns a read-only (constant) iterator that points one past the last
00332        *  pair in the %map.  Iteration is done in ascending order according to
00333        *  the keys.
00334        */
00335       const_iterator
00336       end() const
00337       { return _M_t.end(); }
00338 
00339       /**
00340        *  Returns a read/write reverse iterator that points to the last pair in
00341        *  the %map.  Iteration is done in descending order according to the
00342        *  keys.
00343        */
00344       reverse_iterator
00345       rbegin()
00346       { return _M_t.rbegin(); }
00347 
00348       /**
00349        *  Returns a read-only (constant) reverse iterator that points to the
00350        *  last pair in the %map.  Iteration is done in descending order
00351        *  according to the keys.
00352        */
00353       const_reverse_iterator
00354       rbegin() const
00355       { return _M_t.rbegin(); }
00356 
00357       /**
00358        *  Returns a read/write reverse iterator that points to one before the
00359        *  first pair in the %map.  Iteration is done in descending order
00360        *  according to the keys.
00361        */
00362       reverse_iterator
00363       rend()
00364       { return _M_t.rend(); }
00365 
00366       /**
00367        *  Returns a read-only (constant) reverse iterator that points to one
00368        *  before the first pair in the %map.  Iteration is done in descending
00369        *  order according to the keys.
00370        */
00371       const_reverse_iterator
00372       rend() const
00373       { return _M_t.rend(); }
00374 
00375 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00376       /**
00377        *  Returns a read-only (constant) iterator that points to the first pair
00378        *  in the %map.  Iteration is done in ascending order according to the
00379        *  keys.
00380        */
00381       const_iterator
00382       cbegin() const
00383       { return _M_t.begin(); }
00384 
00385       /**
00386        *  Returns a read-only (constant) iterator that points one past the last
00387        *  pair in the %map.  Iteration is done in ascending order according to
00388        *  the keys.
00389        */
00390       const_iterator
00391       cend() const
00392       { return _M_t.end(); }
00393 
00394       /**
00395        *  Returns a read-only (constant) reverse iterator that points to the
00396        *  last pair in the %map.  Iteration is done in descending order
00397        *  according to the keys.
00398        */
00399       const_reverse_iterator
00400       crbegin() const
00401       { return _M_t.rbegin(); }
00402 
00403       /**
00404        *  Returns a read-only (constant) reverse iterator that points to one
00405        *  before the first pair in the %map.  Iteration is done in descending
00406        *  order according to the keys.
00407        */
00408       const_reverse_iterator
00409       crend() const
00410       { return _M_t.rend(); }
00411 #endif
00412 
00413       // capacity
00414       /** Returns true if the %map is empty.  (Thus begin() would equal
00415        *  end().)
00416       */
00417       bool
00418       empty() const
00419       { return _M_t.empty(); }
00420 
00421       /** Returns the size of the %map.  */
00422       size_type
00423       size() const
00424       { return _M_t.size(); }
00425 
00426       /** Returns the maximum size of the %map.  */
00427       size_type
00428       max_size() const
00429       { return _M_t.max_size(); }
00430 
00431       // [23.3.1.2] element access
00432       /**
00433        *  @brief  Subscript ( @c [] ) access to %map data.
00434        *  @param  k  The key for which data should be retrieved.
00435        *  @return  A reference to the data of the (key,data) %pair.
00436        *
00437        *  Allows for easy lookup with the subscript ( @c [] )
00438        *  operator.  Returns data associated with the key specified in
00439        *  subscript.  If the key does not exist, a pair with that key
00440        *  is created using default values, which is then returned.
00441        *
00442        *  Lookup requires logarithmic time.
00443        */
00444       mapped_type&
00445       operator[](const key_type& __k)
00446       {
00447     // concept requirements
00448     __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
00449 
00450     iterator __i = lower_bound(__k);
00451     // __i->first is greater than or equivalent to __k.
00452     if (__i == end() || key_comp()(__k, (*__i).first))
00453           __i = insert(__i, value_type(__k, mapped_type()));
00454     return (*__i).second;
00455       }
00456 
00457 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00458       mapped_type&
00459       operator[](key_type&& __k)
00460       {
00461     // concept requirements
00462     __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
00463 
00464     iterator __i = lower_bound(__k);
00465     // __i->first is greater than or equivalent to __k.
00466     if (__i == end() || key_comp()(__k, (*__i).first))
00467           __i = insert(__i, std::make_pair(std::move(__k), mapped_type()));
00468     return (*__i).second;
00469       }
00470 #endif
00471 
00472       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00473       // DR 464. Suggestion for new member functions in standard containers.
00474       /**
00475        *  @brief  Access to %map data.
00476        *  @param  k  The key for which data should be retrieved.
00477        *  @return  A reference to the data whose key is equivalent to @a k, if
00478        *           such a data is present in the %map.
00479        *  @throw  std::out_of_range  If no such data is present.
00480        */
00481       mapped_type&
00482       at(const key_type& __k)
00483       {
00484     iterator __i = lower_bound(__k);
00485     if (__i == end() || key_comp()(__k, (*__i).first))
00486       __throw_out_of_range(__N("map::at"));
00487     return (*__i).second;
00488       }
00489 
00490       const mapped_type&
00491       at(const key_type& __k) const
00492       {
00493     const_iterator __i = lower_bound(__k);
00494     if (__i == end() || key_comp()(__k, (*__i).first))
00495       __throw_out_of_range(__N("map::at"));
00496     return (*__i).second;
00497       }
00498 
00499       // modifiers
00500       /**
00501        *  @brief Attempts to insert a std::pair into the %map.
00502 
00503        *  @param  x  Pair to be inserted (see std::make_pair for easy creation 
00504        *         of pairs).
00505 
00506        *  @return  A pair, of which the first element is an iterator that 
00507        *           points to the possibly inserted pair, and the second is 
00508        *           a bool that is true if the pair was actually inserted.
00509        *
00510        *  This function attempts to insert a (key, value) %pair into the %map.
00511        *  A %map relies on unique keys and thus a %pair is only inserted if its
00512        *  first element (the key) is not already present in the %map.
00513        *
00514        *  Insertion requires logarithmic time.
00515        */
00516       std::pair<iterator, bool>
00517       insert(const value_type& __x)
00518       { return _M_t._M_insert_unique(__x); }
00519 
00520 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00521       template<typename _Pair, typename = typename
00522            std::enable_if<std::is_convertible<_Pair,
00523                           value_type>::value>::type>
00524         std::pair<iterator, bool>
00525         insert(_Pair&& __x)
00526         { return _M_t._M_insert_unique(std::forward<_Pair>(__x)); }
00527 #endif
00528 
00529 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00530       /**
00531        *  @brief Attempts to insert a list of std::pairs into the %map.
00532        *  @param  list  A std::initializer_list<value_type> of pairs to be
00533        *                inserted.
00534        *
00535        *  Complexity similar to that of the range constructor.
00536        */
00537       void
00538       insert(std::initializer_list<value_type> __list)
00539       { insert(__list.begin(), __list.end()); }
00540 #endif
00541 
00542       /**
00543        *  @brief Attempts to insert a std::pair into the %map.
00544        *  @param  position  An iterator that serves as a hint as to where the
00545        *                    pair should be inserted.
00546        *  @param  x  Pair to be inserted (see std::make_pair for easy creation
00547        *             of pairs).
00548        *  @return  An iterator that points to the element with key of @a x (may
00549        *           or may not be the %pair passed in).
00550        *
00551 
00552        *  This function is not concerned about whether the insertion
00553        *  took place, and thus does not return a boolean like the
00554        *  single-argument insert() does.  Note that the first
00555        *  parameter is only a hint and can potentially improve the
00556        *  performance of the insertion process.  A bad hint would
00557        *  cause no gains in efficiency.
00558        *
00559        *  See
00560        *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
00561        *  for more on @a hinting.
00562        *
00563        *  Insertion requires logarithmic time (if the hint is not taken).
00564        */
00565       iterator
00566 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00567       insert(const_iterator __position, const value_type& __x)
00568 #else
00569       insert(iterator __position, const value_type& __x)
00570 #endif
00571       { return _M_t._M_insert_unique_(__position, __x); }
00572 
00573 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00574       template<typename _Pair, typename = typename
00575            std::enable_if<std::is_convertible<_Pair,
00576                           value_type>::value>::type>
00577         iterator
00578         insert(const_iterator __position, _Pair&& __x)
00579         { return _M_t._M_insert_unique_(__position,
00580                     std::forward<_Pair>(__x)); }
00581 #endif
00582 
00583       /**
00584        *  @brief Template function that attempts to insert a range of elements.
00585        *  @param  first  Iterator pointing to the start of the range to be
00586        *                 inserted.
00587        *  @param  last  Iterator pointing to the end of the range.
00588        *
00589        *  Complexity similar to that of the range constructor.
00590        */
00591       template<typename _InputIterator>
00592         void
00593         insert(_InputIterator __first, _InputIterator __last)
00594         { _M_t._M_insert_unique(__first, __last); }
00595 
00596 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00597       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00598       // DR 130. Associative erase should return an iterator.
00599       /**
00600        *  @brief Erases an element from a %map.
00601        *  @param  position  An iterator pointing to the element to be erased.
00602        *  @return An iterator pointing to the element immediately following
00603        *          @a position prior to the element being erased. If no such 
00604        *          element exists, end() is returned.
00605        *
00606        *  This function erases an element, pointed to by the given
00607        *  iterator, from a %map.  Note that this function only erases
00608        *  the element, and that if the element is itself a pointer,
00609        *  the pointed-to memory is not touched in any way.  Managing
00610        *  the pointer is the user's responsibility.
00611        */
00612       iterator
00613       erase(const_iterator __position)
00614       { return _M_t.erase(__position); }
00615 #else
00616       /**
00617        *  @brief Erases an element from a %map.
00618        *  @param  position  An iterator pointing to the element to be erased.
00619        *
00620        *  This function erases an element, pointed to by the given
00621        *  iterator, from a %map.  Note that this function only erases
00622        *  the element, and that if the element is itself a pointer,
00623        *  the pointed-to memory is not touched in any way.  Managing
00624        *  the pointer is the user's responsibility.
00625        */
00626       void
00627       erase(iterator __position)
00628       { _M_t.erase(__position); }
00629 #endif
00630 
00631       /**
00632        *  @brief Erases elements according to the provided key.
00633        *  @param  x  Key of element to be erased.
00634        *  @return  The number of elements erased.
00635        *
00636        *  This function erases all the elements located by the given key from
00637        *  a %map.
00638        *  Note that this function only erases the element, and that if
00639        *  the element is itself a pointer, the pointed-to memory is not touched
00640        *  in any way.  Managing the pointer is the user's responsibility.
00641        */
00642       size_type
00643       erase(const key_type& __x)
00644       { return _M_t.erase(__x); }
00645 
00646 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00647       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00648       // DR 130. Associative erase should return an iterator.
00649       /**
00650        *  @brief Erases a [first,last) range of elements from a %map.
00651        *  @param  first  Iterator pointing to the start of the range to be
00652        *                 erased.
00653        *  @param  last  Iterator pointing to the end of the range to be erased.
00654        *  @return The iterator @a last.
00655        *
00656        *  This function erases a sequence of elements from a %map.
00657        *  Note that this function only erases the element, and that if
00658        *  the element is itself a pointer, the pointed-to memory is not touched
00659        *  in any way.  Managing the pointer is the user's responsibility.
00660        */
00661       iterator
00662       erase(const_iterator __first, const_iterator __last)
00663       { return _M_t.erase(__first, __last); }
00664 #else
00665       /**
00666        *  @brief Erases a [first,last) range of elements from a %map.
00667        *  @param  first  Iterator pointing to the start of the range to be
00668        *                 erased.
00669        *  @param  last  Iterator pointing to the end of the range to be erased.
00670        *
00671        *  This function erases a sequence of elements from a %map.
00672        *  Note that this function only erases the element, and that if
00673        *  the element is itself a pointer, the pointed-to memory is not touched
00674        *  in any way.  Managing the pointer is the user's responsibility.
00675        */
00676       void
00677       erase(iterator __first, iterator __last)
00678       { _M_t.erase(__first, __last); }
00679 #endif
00680 
00681       /**
00682        *  @brief  Swaps data with another %map.
00683        *  @param  x  A %map of the same element and allocator types.
00684        *
00685        *  This exchanges the elements between two maps in constant
00686        *  time.  (It is only swapping a pointer, an integer, and an
00687        *  instance of the @c Compare type (which itself is often
00688        *  stateless and empty), so it should be quite fast.)  Note
00689        *  that the global std::swap() function is specialized such
00690        *  that std::swap(m1,m2) will feed to this function.
00691        */
00692       void
00693       swap(map& __x)
00694       { _M_t.swap(__x._M_t); }
00695 
00696       /**
00697        *  Erases all elements in a %map.  Note that this function only
00698        *  erases the elements, and that if the elements themselves are
00699        *  pointers, the pointed-to memory is not touched in any way.
00700        *  Managing the pointer is the user's responsibility.
00701        */
00702       void
00703       clear()
00704       { _M_t.clear(); }
00705 
00706       // observers
00707       /**
00708        *  Returns the key comparison object out of which the %map was
00709        *  constructed.
00710        */
00711       key_compare
00712       key_comp() const
00713       { return _M_t.key_comp(); }
00714 
00715       /**
00716        *  Returns a value comparison object, built from the key comparison
00717        *  object out of which the %map was constructed.
00718        */
00719       value_compare
00720       value_comp() const
00721       { return value_compare(_M_t.key_comp()); }
00722 
00723       // [23.3.1.3] map operations
00724       /**
00725        *  @brief Tries to locate an element in a %map.
00726        *  @param  x  Key of (key, value) %pair to be located.
00727        *  @return  Iterator pointing to sought-after element, or end() if not
00728        *           found.
00729        *
00730        *  This function takes a key and tries to locate the element with which
00731        *  the key matches.  If successful the function returns an iterator
00732        *  pointing to the sought after %pair.  If unsuccessful it returns the
00733        *  past-the-end ( @c end() ) iterator.
00734        */
00735       iterator
00736       find(const key_type& __x)
00737       { return _M_t.find(__x); }
00738 
00739       /**
00740        *  @brief Tries to locate an element in a %map.
00741        *  @param  x  Key of (key, value) %pair to be located.
00742        *  @return  Read-only (constant) iterator pointing to sought-after
00743        *           element, or end() if not found.
00744        *
00745        *  This function takes a key and tries to locate the element with which
00746        *  the key matches.  If successful the function returns a constant
00747        *  iterator pointing to the sought after %pair. If unsuccessful it
00748        *  returns the past-the-end ( @c end() ) iterator.
00749        */
00750       const_iterator
00751       find(const key_type& __x) const
00752       { return _M_t.find(__x); }
00753 
00754       /**
00755        *  @brief  Finds the number of elements with given key.
00756        *  @param  x  Key of (key, value) pairs to be located.
00757        *  @return  Number of elements with specified key.
00758        *
00759        *  This function only makes sense for multimaps; for map the result will
00760        *  either be 0 (not present) or 1 (present).
00761        */
00762       size_type
00763       count(const key_type& __x) const
00764       { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
00765 
00766       /**
00767        *  @brief Finds the beginning of a subsequence matching given key.
00768        *  @param  x  Key of (key, value) pair to be located.
00769        *  @return  Iterator pointing to first element equal to or greater
00770        *           than key, or end().
00771        *
00772        *  This function returns the first element of a subsequence of elements
00773        *  that matches the given key.  If unsuccessful it returns an iterator
00774        *  pointing to the first element that has a greater value than given key
00775        *  or end() if no such element exists.
00776        */
00777       iterator
00778       lower_bound(const key_type& __x)
00779       { return _M_t.lower_bound(__x); }
00780 
00781       /**
00782        *  @brief Finds the beginning of a subsequence matching given key.
00783        *  @param  x  Key of (key, value) pair to be located.
00784        *  @return  Read-only (constant) iterator pointing to first element
00785        *           equal to or greater than key, or end().
00786        *
00787        *  This function returns the first element of a subsequence of elements
00788        *  that matches the given key.  If unsuccessful it returns an iterator
00789        *  pointing to the first element that has a greater value than given key
00790        *  or end() if no such element exists.
00791        */
00792       const_iterator
00793       lower_bound(const key_type& __x) const
00794       { return _M_t.lower_bound(__x); }
00795 
00796       /**
00797        *  @brief Finds the end of a subsequence matching given key.
00798        *  @param  x  Key of (key, value) pair to be located.
00799        *  @return Iterator pointing to the first element
00800        *          greater than key, or end().
00801        */
00802       iterator
00803       upper_bound(const key_type& __x)
00804       { return _M_t.upper_bound(__x); }
00805 
00806       /**
00807        *  @brief Finds the end of a subsequence matching given key.
00808        *  @param  x  Key of (key, value) pair to be located.
00809        *  @return  Read-only (constant) iterator pointing to first iterator
00810        *           greater than key, or end().
00811        */
00812       const_iterator
00813       upper_bound(const key_type& __x) const
00814       { return _M_t.upper_bound(__x); }
00815 
00816       /**
00817        *  @brief Finds a subsequence matching given key.
00818        *  @param  x  Key of (key, value) pairs to be located.
00819        *  @return  Pair of iterators that possibly points to the subsequence
00820        *           matching given key.
00821        *
00822        *  This function is equivalent to
00823        *  @code
00824        *    std::make_pair(c.lower_bound(val),
00825        *                   c.upper_bound(val))
00826        *  @endcode
00827        *  (but is faster than making the calls separately).
00828        *
00829        *  This function probably only makes sense for multimaps.
00830        */
00831       std::pair<iterator, iterator>
00832       equal_range(const key_type& __x)
00833       { return _M_t.equal_range(__x); }
00834 
00835       /**
00836        *  @brief Finds a subsequence matching given key.
00837        *  @param  x  Key of (key, value) pairs to be located.
00838        *  @return  Pair of read-only (constant) iterators that possibly points
00839        *           to the subsequence matching given key.
00840        *
00841        *  This function is equivalent to
00842        *  @code
00843        *    std::make_pair(c.lower_bound(val),
00844        *                   c.upper_bound(val))
00845        *  @endcode
00846        *  (but is faster than making the calls separately).
00847        *
00848        *  This function probably only makes sense for multimaps.
00849        */
00850       std::pair<const_iterator, const_iterator>
00851       equal_range(const key_type& __x) const
00852       { return _M_t.equal_range(__x); }
00853 
00854       template<typename _K1, typename _T1, typename _C1, typename _A1>
00855         friend bool
00856         operator==(const map<_K1, _T1, _C1, _A1>&,
00857            const map<_K1, _T1, _C1, _A1>&);
00858 
00859       template<typename _K1, typename _T1, typename _C1, typename _A1>
00860         friend bool
00861         operator<(const map<_K1, _T1, _C1, _A1>&,
00862           const map<_K1, _T1, _C1, _A1>&);
00863     };
00864 
00865   /**
00866    *  @brief  Map equality comparison.
00867    *  @param  x  A %map.
00868    *  @param  y  A %map of the same type as @a x.
00869    *  @return  True iff the size and elements of the maps are equal.
00870    *
00871    *  This is an equivalence relation.  It is linear in the size of the
00872    *  maps.  Maps are considered equivalent if their sizes are equal,
00873    *  and if corresponding elements compare equal.
00874   */
00875   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00876     inline bool
00877     operator==(const map<_Key, _Tp, _Compare, _Alloc>& __x,
00878                const map<_Key, _Tp, _Compare, _Alloc>& __y)
00879     { return __x._M_t == __y._M_t; }
00880 
00881   /**
00882    *  @brief  Map ordering relation.
00883    *  @param  x  A %map.
00884    *  @param  y  A %map of the same type as @a x.
00885    *  @return  True iff @a x is lexicographically less than @a y.
00886    *
00887    *  This is a total ordering relation.  It is linear in the size of the
00888    *  maps.  The elements must be comparable with @c <.
00889    *
00890    *  See std::lexicographical_compare() for how the determination is made.
00891   */
00892   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00893     inline bool
00894     operator<(const map<_Key, _Tp, _Compare, _Alloc>& __x,
00895               const map<_Key, _Tp, _Compare, _Alloc>& __y)
00896     { return __x._M_t < __y._M_t; }
00897 
00898   /// Based on operator==
00899   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00900     inline bool
00901     operator!=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
00902                const map<_Key, _Tp, _Compare, _Alloc>& __y)
00903     { return !(__x == __y); }
00904 
00905   /// Based on operator<
00906   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00907     inline bool
00908     operator>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
00909               const map<_Key, _Tp, _Compare, _Alloc>& __y)
00910     { return __y < __x; }
00911 
00912   /// Based on operator<
00913   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00914     inline bool
00915     operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
00916                const map<_Key, _Tp, _Compare, _Alloc>& __y)
00917     { return !(__y < __x); }
00918 
00919   /// Based on operator<
00920   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00921     inline bool
00922     operator>=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
00923                const map<_Key, _Tp, _Compare, _Alloc>& __y)
00924     { return !(__x < __y); }
00925 
00926   /// See std::map::swap().
00927   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00928     inline void
00929     swap(map<_Key, _Tp, _Compare, _Alloc>& __x,
00930      map<_Key, _Tp, _Compare, _Alloc>& __y)
00931     { __x.swap(__y); }
00932 
00933 _GLIBCXX_END_NAMESPACE_CONTAINER
00934 } // namespace std
00935 
00936 #endif /* _STL_MAP_H */