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hash_map(C++std)


hash_compare , hash_map , hash_multimap , operator== , operator!= , operator< , operator> , operator<= , operator>= , swap - defines template classes that implement hashed associative containers that map keys to values (standard template library)

Synopsis

   namespace sco_std {
   template<class Key, class Bop>
       class hash_compare;
   template<class Key, class T, class Pred, class A>
       class hash_map;
   template<class Key, class T, class Pred, class A>
       class hash_multimap;

           // TEMPLATE FUNCTIONS
   template<class Key, class T, class Pred, class A>
       bool operator==(
           const hash_map<Key, T, Pred, A>& lhs,
           const hash_map<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator==(
           const hash_multimap<Key, T, Pred, A>& lhs,
           const hash_multimap<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator!=(
           const hash_map<Key, T, Pred, A>& lhs,
           const hash_map<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator!=(
           const hash_multimap<Key, T, Pred, A>& lhs,
           const hash_multimap<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator<(
           const hash_map<Key, T, Pred, A>& lhs,
           const hash_map<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator<(
           const hash_multimap<Key, T, Pred, A>& lhs,
           const hash_multimap<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator>(
           const hash_map<Key, T, Pred, A>& lhs,
           const hash_map<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator>(
           const hash_multimap<Key, T, Pred, A>& lhs,
           const hash_multimap<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator<=(
           const hash_map<Key, T, Pred, A>& lhs,
           const hash_map<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator<=(
           const hash_multimap<Key, T, Pred, A>& lhs,
           const hash_multimap<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator>=(
           const hash_map<Key, T, Pred, A>& lhs,
           const hash_map<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator>=(
           const hash_multimap<Key, T, Pred, A>& lhs,
           const hash_multimap<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       void swap(
           hash_map<Key, T, Pred, A>& lhs,
           hash_map<Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       void swap(
           hash_multimap<Key, T, Pred, A>& lhs,
           hash_multimap<Key, T, Pred, A>& rhs);
       };


NOTE: The namespace ``sco_std'' is an extension to the ISO standard.

Description

Include the STL standard header <hash_map> to define the container template classes hash_map and hash_multimap, and their supporting templates.

hash_compare

   template<class Key,
       class Bop = less<Key> >
       class hash_compare {
       Bop comp;
   public:
       const size_t bucket_size = 4;
       const size_t min_buckets = 8;
       hash_compare();
       hash_compare(Bop parg);
       size_t operator()(const Key& Key) const;
       bool operator()(const Key& key1,
           const Key& key2) const;
       };

The template class describes an object that can be used by any of the containers hash_map, hash_multimap, hash_set, or hash_multiset to order the sequence it controls. Each of these stores a function object of type Bop (a template parameter). You can derive a class from a specialization of hash_compare, to selectively override certain functions and objects. Or you can supply your own version of this class, provided you meet certain minimum requirements. Specifically, for an object hash_comp of type hash_compare<Key, Bop>, the following behavior is required by the above containers:

hash_map


allocator_type , begin , clear , const_iterator , const_pointer , const_reference , const_reverse_iterator , count , difference_type , empty , end , equal_range , erase , find , get_allocator , insert , iterator , key_comp , key_compare , key_type , lower_bound , hash_map , mapped_type , max_size , operator[] , pointer , rbegin , reference , rend , reverse_iterator , size , size_type , swap , upper_bound , value_comp , value_compare , value_type

   template<class Key, class T,
       class Pred = hash_compare<Key, less<Key> >,
       class A = allocator<pair<const Key, T> > >
       class hash_map {
   public:
       typedef Key key_type;
       typedef T mapped_type;
       typedef Pred key_compare;
       typedef A allocator_type;
       typedef pair<const Key, T> value_type;
       class value_compare;
       typedef A::pointer pointer;
       typedef A::const_pointer const_pointer;
       typedef A::reference reference;
       typedef A::const_reference const_reference;
       typedef T0 iterator;
       typedef T1 const_iterator;
       typedef T2 size_type;
       typedef T3 difference_type;
       typedef reverse_iterator<const_iterator>
           const_reverse_iterator;
       typedef reverse_iterator<iterator> reverse_iterator;
       hash_map();
       explicit hash_map(const Pred& comp);
       hash_map(const Pred& comp, const A& al);
       hash_map(const hash_map& x);
       template<class InIt>
           hash_map(InIt first, InIt last);
       template<class InIt>
           hash_map(InIt first, InIt last,
               const Pred& comp);
       template<class InIt>
           hash_map(InIt first, InIt last,
               const Pred& comp, const A& al);
       iterator begin();
       const_iterator begin() const;
       iterator end();
       const_iterator end() const;
       reverse_iterator rbegin();
       const_reverse_iterator rbegin() const;
       reverse_iterator rend();
       const_reverse_iterator rend() const;
       size_type size() const;
       size_type max_size() const;
       bool empty() const;
       A get_allocator() const;
       mapped_type operator[](const Key& key);
       pair<iterator, bool> insert(const value_type& x);
       iterator insert(iterator it, const value_type& x);
       template<class InIt>
           void insert(InIt first, InIt last);
       iterator erase(iterator it);
       iterator erase(iterator first, iterator last);
       size_type erase(const Key& key);
       void clear();
       void swap(hash_map& x);
       key_compare key_comp() const;
       value_compare value_comp() const;
       iterator find(const Key& key);
       const_iterator find(const Key& key) const;
       size_type count(const Key& key) const;
       iterator lower_bound(const Key& key);
       const_iterator lower_bound(const Key& key) const;
       iterator upper_bound(const Key& key);
       const_iterator upper_bound(const Key& key) const;
       pair<iterator, iterator> equal_range(const Key& key);
       pair<const_iterator, const_iterator>
           equal_range(const Key& key) const;
       };

The template class describes an object that controls a varying-length sequence of elements of type pair<const Key, T>. The sequence is ordered by the function object Pred, which includes both a two-operand function for imposing a total ordering and a one-operand hash function. The first element of each pair is the sort key and the second is its associated value. The sequence is represented in a way that permits lookup, insertion, and removal of an arbitrary element with a number of operations that can be independent of the number of elements in the sequence (constant time). In the worst case, the number of operations is proportional to the number of elements in the sequence (linear time). Moreover, inserting an element invalidates no iterators, and removing an element invalidates only those iterators which point at the removed element.

The object orders the sequence it controls by calling a stored function object of type Pred. You access this stored object by calling the member function key_comp(). Such a function object must behave the same as an object of class hash_compare<Key, Bop>. Specifically, for all values key of type Key, the call key_comp()(key) yields a distribution of values of type size_t. Moreover, class Bop imposes a total ordering on sort keys of type Key. For any element x that precedes y in the sequence and has the same hash value, key_comp()(y.first, x.first) is false. (For the default function object less<Key>, sort keys never decrease in value.) Unlike template class hash_multimap, an object of template class hash_map ensures that key_comp()(x.first, y.first) is true. (Each key is unique.)

The actual order of elements in the controlled sequence depends on the hash function, the ordering function, and the current size of the hash table stored in the container object. You cannot determine the current size of the hash table, so you cannot in general predict the order of elements in the controlled sequence.

The object allocates and frees storage for the sequence it controls through a stored allocator object of class A. Such an allocator object must have the same external interface as an object of template class allocator. Note that the stored allocator object is not copied when the container object is assigned.

hash_map::allocator_type

   typedef A allocator_type;

The type is a synonym for the template parameter A.

hash_map::begin

   const_iterator begin() const;
   iterator begin();

The member function returns a bidirectional iterator that points at the first element of the sequence (or just beyond the end of an empty sequence).

hash_map::clear

   void clear();

The member function calls erase( begin(), end()).

hash_map::const_iterator

   typedef T1 const_iterator;

The type describes an object that can serve as a constant bidirectional iterator for the controlled sequence. It is described here as a synonym for the implementation-defined type T1.

hash_map::const_pointer

   typedef A::const_pointer const_pointer;

The type describes an object that can serve as a constant pointer to an element of the controlled sequence.

hash_map::const_reference

   typedef A::const_reference const_reference;

The type describes an object that can serve as a constant reference to an element of the controlled sequence.

hash_map::const_reverse_iterator

   typedef reverse_iterator<const_iterator>
       const_reverse_iterator;

The type describes an object that can serve as a constant reverse bidirectional iterator for the controlled sequence.

hash_map::count

   size_type count(const Key& key) const;

The member function returns the number of elements x in the range [lower_bound(key), upper_bound(key)).

hash_map::difference_type

   typedef T3 difference_type;

The signed integer type describes an object that can represent the difference between the addresses of any two elements in the controlled sequence. It is described here as a synonym for the implementation-defined type T3.

hash_map::empty

   bool empty() const;

The member function returns true for an empty controlled sequence.

hash_map::end

   const_iterator end() const;
   iterator end();

The member function returns a bidirectional iterator that points just beyond the end of the sequence.

hash_map::equal_range

   pair<iterator, iterator> equal_range(const Key& key);
   pair<const_iterator, const_iterator>
       equal_range(const Key& key) const;

The member function returns a pair of iterators x such that x.first == lower_bound(key) and x.second == upper_bound(key).

hash_map::erase

   iterator erase(iterator it);
   iterator erase(iterator first, iterator last);
   size_type erase(const Key& key);

The first member function removes the element of the controlled sequence pointed to by it. The second member function removes the elements in the interval [first, last). Both return an iterator that designates the first element remaining beyond any elements removed, or end() if no such element exists.

The third member function removes the elements with sort keys in the range [lower_bound(key), upper_bound(key)). It returns the number of elements it removes.

The member functions never throw an exception.

hash_map::find

   iterator find(const Key& key);
   const_iterator find(const Key& key) const;

The member function returns lower_bound(key).

hash_map::get_allocator

   A get_allocator() const;

The member function returns the stored allocator object.

hash_map::hash_map

   hash_map();
   explicit hash_map(const Pred& comp);
   hash_map(const Pred& comp, const A& al);
   hash_map(const hash_map& x);
   template<class InIt>
       hash_map(InIt first, InIt last);
   template<class InIt>
       hash_map(InIt first, InIt last,
           const Pred& comp);
   template<class InIt>
       hash_map(InIt first, InIt last,
           const Pred& comp, const A& al);

All constructors store an allocator object and initialize the controlled sequence. The allocator object is the argument al, if present. For the copy constructor, it is x.get_allocator(). Otherwise, it is A().

All constructors also store a function object that can later be returned by calling key_comp(). The function object is the argument comp, if present. For the copy constructor, it is x.key_comp()). Otherwise, it is Pred().

The first three constructors specify an empty initial controlled sequence. The fourth constructor specifies a copy of the sequence controlled by x. The last three constructors specify the sequence of element values [first, last).

hash_map::insert

   pair<iterator, bool> insert(const value_type& x);
   iterator insert(iterator it, const value_type& x);
   template<class InIt>
       void insert(InIt first, InIt last);

The first member function determines whether an element y exists in the sequence whose key has equivalent ordering to that of x. If not, it creates such an element y and initializes it with x. The function then determines the iterator it that designates y. If an insertion occurred, the function returns pair(it, true). Otherwise, it returns pair(it, false).

The second member function returns insert(x).first, using it as a starting place within the controlled sequence to search for the insertion point. (Insertion can possibly occur somewhat faster, if the insertion point immediately precedes it.) The third member function inserts the sequence of element values, for each it in the range [first, last), by calling insert(*it).

If an exception is thrown during the insertion of a single element, the container is left unaltered and the exception is rethrown. If an exception is thrown during the insertion of multiple elements, the container is left in a stable but unspecified state and the exception is rethrown.

hash_map::iterator

   typedef T0 iterator;

The type describes an object that can serve as a bidirectional iterator for the controlled sequence. It is described here as a synonym for the implementation-defined type T0.

hash_map::key_comp

   key_compare key_comp() const;

The member function returns the stored function object that determines the order of elements in the controlled sequence. In particular, the stored object defines the member function:

   bool operator()(const Key& x, const Key& y);

which returns true if x strictly precedes y in the sort order.

hash_map::key_compare

   typedef Pred key_compare;

The type describes a function object that behaves much like an object of class hash_compare<Key, Bop>. In particular, it can compare two sort keys to determine the relative order of two elements in the controlled sequence.

hash_map::key_type

   typedef Key key_type;

The type describes the sort key object stored in each element of the controlled sequence.

hash_map::lower_bound

   iterator lower_bound(const Key& key);
   const_iterator lower_bound(const Key& key) const;

The member function returns an iterator that designates the earliest element x in the controlled sequence for which x.first has equivalent ordering to key. If no such element exists, the function returns end().

hash_map::mapped_type

   typedef T mapped_type;

The type is a synonym for the template parameter T.

hash_map::max_size

   size_type max_size() const;

The member function returns the length of the longest sequence that the object can control.

hash_map::operator[]

   T& operator[](const Key& key);

The member function determines the iterator it as the return value of insert( value_type(key, T()). (It inserts an element with the specified key if no such element exists.) It then returns a reference to (*it).second.

hash_map::pointer

   typedef A::pointer pointer;

The type describes an object that can serve as a pointer to an element of the controlled sequence.

hash_map::rbegin

   const_reverse_iterator rbegin() const;
   reverse_iterator rbegin();

The member function returns a reverse bidirectional iterator that points just beyond the end of the controlled sequence. Hence, it designates the beginning of the reverse sequence.

hash_map::reference

   typedef A::reference reference;

The type describes an object that can serve as a reference to an element of the controlled sequence.

hash_map::rend

   const_reverse_iterator rend() const;
   reverse_iterator rend();

The member function returns a reverse bidirectional iterator that points at the first element of the sequence (or just beyond the end of an empty sequence). Hence, it designates the end of the reverse sequence.

hash_map::reverse_iterator

   typedef reverse_iterator<iterator> reverse_iterator;

The type describes an object that can serve as a reverse bidirectional iterator for the controlled sequence.

hash_map::size

   size_type size() const;

The member function returns the length of the controlled sequence.

hash_map::size_type

   typedef T2 size_type;

The unsigned integer type describes an object that can represent the length of any controlled sequence. It is described here as a synonym for the implementation-defined type T2.

hash_map::swap

   void swap(hash_map& x);

The member function swaps the controlled sequences between *this and x. If get_allocator() == x.get_allocator(), it does so in constant time, it throws an exception only as a result of copying the stored function object of type Pred, and it invalidates no references, pointers, or iterators that designate elements in the two controlled sequences. Otherwise, it performs a number of element assignments and constructor calls proportional to the number of elements in the two controlled sequences.

hash_map::upper_bound

   iterator upper_bound(const Key& key);
   const_iterator upper_bound(const Key& key) const;

The member function returns an iterator just beyond the iterator that designates the latest element x in the controlled sequence for which x.first has equivalent ordering to key. If no such element exists, the function returns end().

hash_map::value_comp

   value_compare value_comp() const;

The member function returns a function object that determines the order of elements in the controlled sequence.

hash_map::value_compare

   class value_compare
       : public binary_function<value_type, value_type,
           bool> {
   public:
       bool operator()(const value_type& x,
           const value_type& y) const
           {return (comp(x.first, y.first)); }
   protected:
       value_compare(key_compare pr)
           : comp(pr) {}
       key_compare comp;
       };

The type describes a function object that can compare the sort keys in two elements to determine their relative order in the controlled sequence. The function object stores an object comp of type key_type. The member function operator() uses this object to compare the sort-key components of two element.

hash_map::value_type

   typedef pair<const Key, T> value_type;

The type describes an element of the controlled sequence.

hash_multimap


allocator_type , begin , clear , const_iterator , const_pointer , const_reference , const_reverse_iterator , count , difference_type , empty , end , equal_range , erase , find , get_allocator , insert , iterator , key_comp , key_compare , key_type , lower_bound , mapped_type , max_size , hash_multimap , rbegin , reference , rend , reverse_iterator , size , size_type , swap , upper_bound , value_comp , value_compare , value_type

   template<class Key, class T,
       class Pred = hash_compare<Key, less<Key> >,
       class A = allocator<pair<const Key, T> > >
       class hash_multimap {
   public:
       typedef Key key_type;
       typedef T mapped_type;
       typedef Pred key_compare;
       typedef A allocator_type;
       typedef pair<const Key, T> value_type;
       class value_compare;
       typedef A::reference reference;
       typedef A::const_reference const_reference;
       typedef T0 iterator;
       typedef T1 const_iterator;
       typedef T2 size_type;
       typedef T3 difference_type;
       typedef reverse_iterator<const_iterator>
           const_reverse_iterator;
       typedef reverse_iterator<iterator> reverse_iterator;
       hash_multimap();
       explicit hash_multimap(const Pred& comp);
       hash_multimap(const Pred& comp, const A& al);
       hash_multimap(const hash_multimap& x);
       template<class InIt>
           hash_multimap(InIt first, InIt last);
       template<class InIt>
           hash_multimap(InIt first, InIt last,
               const Pred& comp);
       template<class InIt>
           hash_multimap(InIt first, InIt last,
               const Pred& comp, const A& al);
       iterator begin();
       const_iterator begin() const;
       iterator end();
       const_iterator end() const;
       reverse_iterator rbegin();
       const_reverse_iterator rbegin() const;
       reverse_iterator rend();
       const_reverse_iterator rend() const;
       size_type size() const;
       size_type max_size() const;
       bool empty() const;
       A get_allocator() const;
       iterator insert(const value_type& x);
       iterator insert(iterator it, const value_type& x);
       template<class InIt>
           void insert(InIt first, InIt last);
       iterator erase(iterator it);
       iterator erase(iterator first, iterator last);
       size_type erase(const Key& key);
       void clear();
       void swap(hash_multimap& x);
       key_compare key_comp() const;
       value_compare value_comp() const;
       iterator find(const Key& key);
       const_iterator find(const Key& key) const;
       size_type count(const Key& key) const;
       iterator lower_bound(const Key& key);
       const_iterator lower_bound(const Key& key) const;
       iterator upper_bound(const Key& key);
       const_iterator upper_bound(const Key& key) const;
       pair<iterator, iterator> equal_range(const Key& key);
       pair<const_iterator, const_iterator>
           equal_range(const Key& key) const;
       };

The template class describes an object that controls a varying-length sequence of elements of type pair<const Key, T>. The sequence is ordered by the function object Pred, which includes both a two-operand function for imposing a total ordering and a one-operand hash function. The first element of each pair is the sort key and the second is its associated value. The sequence is represented in a way that permits lookup, insertion, and removal of an arbitrary element with a number of operations that can be independent of the number of elements in the sequence (constant time). In the worst case, the number of operations is proportional to the number of elements in the sequence (linear time). Moreover, inserting an element invalidates no iterators, and removing an element invalidates only those iterators which point at the removed element.

The object orders the sequence it controls by calling a stored function object of type Pred. You access this stored object by calling the member function key_comp(). Such a function object must behave the same as an object of class hash_compare<Key, Bop>. Specifically, for all values key of type Key, the call key_comp()(key) yields a distribution of values of type size_t. Moreover, class Bop imposes a total ordering on sort keys of type Key. For any element x that precedes y in the sequence and has the same hash value, key_comp()(y.first, x.first) is false. (For the default function object less<Key>, sort keys never decrease in value.) Unlike template class hash_map, an object of template class hash_multimap does not ensure that key_comp()(x.first, y.first) is true. (Keys need not be unique.)

The actual order of elements in the controlled sequence depends on the hash function, the ordering function, and the current size of the hash table stored in the container object. You cannot determine the current size of the hash table, so you cannot in general predict the order of elements in the controlled sequence. You can always be assured, however, that any subset of elements that have equivalent ordering are adjacent in the controlled sequence.

The object allocates and frees storage for the sequence it controls through a stored allocator object of class A. Such an allocator object must have the same external interface as an object of template class allocator. Note that the stored allocator object is not copied when the container object is assigned.

hash_multimap::allocator_type

   typedef A allocator_type;

The type is a synonym for the template parameter A.

hash_multimap::begin

   const_iterator begin() const;
   iterator begin();

The member function returns a bidirectional iterator that points at the first element of the sequence (or just beyond the end of an empty sequence).

hash_multimap::clear

   void clear();

The member function calls erase( begin(), end()).

hash_multimap::const_iterator

   typedef T1 const_iterator;

The type describes an object that can serve as a constant bidirectional iterator for the controlled sequence. It is described here as a synonym for the implementation-defined type T1.

hash_multimap::const_pointer

   typedef A::const_pointer const_pointer;

The type describes an object that can serve as a constant pointer to an element of the controlled sequence.

hash_multimap::const_reference

   typedef A::const_reference const_reference;

The type describes an object that can serve as a constant reference to an element of the controlled sequence.

hash_multimap::const_reverse_iterator

   typedef reverse_iterator<const_iterator>
       const_reverse_iterator;

The type describes an object that can serve as a constant reverse bidirectional iterator for the controlled sequence.

hash_multimap::count

   size_type count(const Key& key) const;

The member function returns the number of elements x in the range [lower_bound(key), upper_bound(key)).

hash_multimap::difference_type

   typedef T3 difference_type;

The signed integer type describes an object that can represent the difference between the addresses of any two elements in the controlled sequence. It is described here as a synonym for the implementation-defined type T3.

hash_multimap::empty

   bool empty() const;

The member function returns true for an empty controlled sequence.

hash_multimap::end

   const_iterator end() const;
   iterator end();

The member function returns a bidirectional iterator that points just beyond the end of the sequence.

hash_multimap::equal_range

   pair<iterator, iterator> equal_range(const Key& key);
   pair<const_iterator, const_iterator>
       equal_range(const Key& key) const;

The member function returns a pair of iterators x such that x.first == lower_bound(key) and x.second == upper_bound(key).

hash_multimap::erase

   iterator erase(iterator it);
   iterator erase(iterator first, iterator last);
   size_type erase(const Key& key);

The first member function removes the element of the controlled sequence pointed to by it. The second member function removes the elements in the range [first, last). Both return an iterator that designates the first element remaining beyond any elements removed, or end() if no such element exists.

The third member removes the elements with sort keys in the range [lower_bound(key), upper_bound(key)). It returns the number of elements it removes.

The member functions never throw an exception.

hash_multimap::find

   iterator find(const Key& key);
   const_iterator find(const Key& key) const;

The member function returns lower_bound(key).

hash_multimap::get_allocator

   A get_allocator() const;

The member function returns the stored allocator object.

hash_multimap::hash_multimap

   hash_multimap();
   explicit hash_multimap(const Pred& comp);
   hash_multimap(const Pred& comp, const A& al);
   hash_multimap(const hash_multimap& x);
   template<class InIt>
       hash_multimap(InIt first, InIt last);
   template<class InIt>
       hash_multimap(InIt first, InIt last,
           const Pred& comp);
   template<class InIt>
       hash_multimap(InIt first, InIt last,
           const Pred& comp, const A& al);

All constructors store an allocator object and initialize the controlled sequence. The allocator object is the argument al, if present. For the copy constructor, it is x.get_allocator(). Otherwise, it is A().

All constructors also store a function object that can later be returned by calling key_comp(). The function object is the argument comp, if present. For the copy constructor, it is x.key_comp()). Otherwise, it is Pred().

The first three constructors specify an empty initial controlled sequence. The fourth constructor specifies a copy of the sequence controlled by x. The last three constructors specify the sequence of element values [first, last).

hash_multimap::insert

   iterator insert(const value_type& x);
   iterator insert(iterator it, const value_type& x);
   template<class InIt>
       void insert(InIt first, InIt last);

The first member function inserts the element x in the controlled sequence, then returns the iterator that designates the inserted element. The second member function returns insert(x), using it as a starting place within the controlled sequence to search for the insertion point. (Insertion can possibly occur somewhat faster, if the insertion point immediately precedes it.) The third member function inserts the sequence of element values, for each it in the range [first, last), by calling insert(*it).

If an exception is thrown during the insertion of a single element, the container is left unaltered and the exception is rethrown. If an exception is thrown during the insertion of multiple elements, the container is left in a stable but unspecified state and the exception is rethrown.

hash_multimap::iterator

   typedef T0 iterator;

The type describes an object that can serve as a bidirectional iterator for the controlled sequence. It is described here as a synonym for the implementation-defined type T0.

hash_multimap::key_comp

   key_compare key_comp() const;

The member function returns the stored function object that determines the order of elements in the controlled sequence. In particular, the stored object defines the member function:

   bool operator()(const Key& x, const Key& y);

which returns true if x strictly precedes y in the sort order.

hash_multimap::key_compare

   typedef Pred key_compare;

The type describes a function object that behaves much like an object of class hash_compare<Key, Bop>. In particular, it can compare two sort keys to determine the relative order of two elements in the controlled sequence.

hash_multimap::key_type

   typedef Key key_type;

The type describes the sort key object stored in each element of the controlled sequence.

hash_multimap::lower_bound

   iterator lower_bound(const Key& key);
   const_iterator lower_bound(const Key& key) const;

The member function returns an iterator that designates the earliest element x in the controlled sequence for which key_comp()(x. first, key) is false.

If no such element exists, the function returns end().

hash_multimap::mapped_type

   typedef T mapped_type;

The type is a synonym for the template parameter T.

hash_multimap::max_size

   size_type max_size() const;

The member function returns the length of the longest sequence that the object can control.

hash_multimap::pointer

   typedef A::pointer pointer;

The type describes an object that can serve as a pointer to an element of the controlled sequence.

hash_multimap::rbegin

   const_reverse_iterator rbegin() const;
   reverse_iterator rbegin();

The member function returns a reverse bidirectional iterator that points just beyond the end of the controlled sequence. Hence, it designates the beginning of the reverse sequence.

hash_multimap::reference

   typedef A::reference reference;

The type describes an object that can serve as a reference to an element of the controlled sequence.

hash_multimap::rend

   const_reverse_iterator rend() const;
   reverse_iterator rend();

The member function returns a reverse bidirectional iterator that points at the first element of the sequence (or just beyond the end of an empty sequence). Hence, it designates the end of the reverse sequence.

hash_multimap::reverse_iterator

   typedef reverse_iterator<iterator> reverse_iterator;

The type describes an object that can serve as a reverse bidirectional iterator for the controlled sequence.

hash_multimap::size

   size_type size() const;

The member function returns the length of the controlled sequence.

hash_multimap::size_type

   typedef T2 size_type;

The unsigned integer type describes an object that can represent the length of any controlled sequence. It is described here as a synonym for the implementation-defined type T2.

hash_multimap::swap

   void swap(hash_multimap& x);

The member function swaps the controlled sequences between *this and x. If get_allocator() == x.get_allocator(), it does so in constant time, it throws an exception only as a result of copying the stored function object of type Pred, and it invalidates no references, pointers, or iterators that designate elements in the two controlled sequences. Otherwise, it performs a number of element assignments and constructor calls proportional to the number of elements in the two controlled sequences.

hash_multimap::upper_bound

   iterator upper_bound(const Key& key);
   const_iterator upper_bound(const Key& key) const;

The member function returns an iterator just beyond the iterator that designates the latest element x in the controlled sequence for which x.first has equivalent ordering to key. If no such element exists, the function returns end().

hash_multimap::value_comp

   value_compare value_comp() const;

The member function returns a function object that determines the order of elements in the controlled sequence.

hash_multimap::value_compare

   class value_compare
       : public binary_function<value_type, value_type,
           bool> {
   public:
       bool operator()(const value_type& x,
           const value_type& y) const
           {return (comp(x.first, x.second)); }
   protected:
       value_compare(key_compare pr)
           : comp(pr) {}
       key_compare comp;
       };

The type describes a function object that can compare the sort keys in two elements to determine their relative order in the controlled sequence. The function object stores an object comp of type key_type. The member function operator() uses this object to compare the sort-key components of two element.

hash_multimap::value_type

   typedef pair<const Key, T> value_type;
   

The type describes an element of the controlled sequence.

operator!=

   template<class Key, class T, class Pred, class A>
       bool operator!=(
           const hash_map <Key, T, Pred, A>& lhs,
           const hash_map <Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator!=(
           const hash_multimap <Key, T, Pred, A>& lhs,
           const hash_multimap <Key, T, Pred, A>& rhs);

The template function returns !(lhs == rhs).

operator==

   template<class Key, class T, class Pred, class A>
       bool operator==(
           const hash_map <Key, T, Pred, A>& lhs,
           const hash_map <Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator==(
           const hash_multimap <Key, T, Pred, A>& lhs,
           const hash_multimap <Key, T, Pred, A>& rhs);

The first template function overloads operator== to compare two objects of template class hash_map. The second template function overloads operator== to compare two objects of template class hash_multimap. Both functions return lhs.size() == rhs.size() && equal(lhs. begin(), lhs. end(), rhs.begin()).

operator<

   template<class Key, class T, class Pred, class A>
       bool operator<(
           const hash_map <Key, T, Pred, A>& lhs,
           const hash_map <Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator<(
           const hash_multimap <Key, T, Pred, A>& lhs,
           const hash_multimap <Key, T, Pred, A>& rhs);

The first template function overloads operator< to compare two objects of template class hash_map. The second template function overloads operator< to compare two objects of template class hash_multimap. Both functions return lexicographical_compare(lhs. begin(), lhs. end(), rhs.begin(), rhs.end(), lhs.value_comp()).

operator<=

   template<class Key, class T, class Pred, class A>
       bool operator<=(
           const hash_map <Key, T, Pred, A>& lhs,
           const hash_map <Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator<=(
           const hash_multimap <Key, T, Pred, A>& lhs,
           const hash_multimap <Key, T, Pred, A>& rhs);

The template function returns !(rhs < lhs).

operator>

   template<class Key, class T, class Pred, class A>
       bool operator>(
           const hash_map <Key, T, Pred, A>& lhs,
           const hash_map <Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator>(
           const hash_multimap <Key, T, Pred, A>& lhs,
           const hash_multimap <Key, T, Pred, A>& rhs);

The template function returns rhs < lhs.

operator>=

   template<class Key, class T, class Pred, class A>
       bool operator>=(
           const hash_map <Key, T, Pred, A>& lhs,
           const hash_map <Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       bool operator!=(
           const hash_multimap <Key, T, Pred, A>& lhs,
           const hash_multimap <Key, T, Pred, A>& rhs);

The template function returns !(lhs < rhs).

swap

   template<class Key, class T, class Pred, class A>
       void swap(
           hash_map <Key, T, Pred, A>& lhs,
           hash_map <Key, T, Pred, A>& rhs);
   template<class Key, class T, class Pred, class A>
       void swap(
           hash_multimap <Key, T, Pred, A>& lhs,
           hash_multimap <Key, T, Pred, A>& rhs);

The template function executes lhs.swap(rhs).

References

algorithm() , functional(C++std) , hash_set(C++std) , memory(C++std) , utility(C++std)
18 February 2000
© 2000 The Santa Cruz Operation, Inc. All rights reserved.

Copyright © 1992-1996 by P.J. Plauger. Portions derived from work copyright © 1994 by Hewlett-Packard Company. All rights reserved.