RWTPtrHashMapIterator(3C++)

Name
     RWTPtrHashMapIterator<K,T,H,EQ> - Rogue Wave library class

Synopsis
              #include<rw/tphdict.h>



              RWTPtrHashMap<K,T,H,EQ> m;
          RWTPtrHashMap<K,T,H,EQ> itr(m);






Please Note!
     If you have the Standard C++ Library, use the interface described here.
     Otherwise, use the interface for RWTPtrHashDictionaryIterator described
     in Appendix A.


Description
     RWTPtrHashMapIterator is supplied with Tools.h++ 7.x to provide an
     iterator interface to the Standard Library based collections that has
     backward compatibility with the container iterators provided in Tools.h++
     6.x. Iteration over an RWTPtrHashMap is pseudorandom and dependent on the
     capacity of the underlying hash table and the hash function being used.
     The current item referenced by this iterator is undefined after
     construction or after a call to reset().  The iterator becomes valid
     after being advanced with either a preincrement or operator().  For both
     operator++ and operator(), iterating past the last element will return a
     value equivalent to boolean false.  Once this state is reached, continued
     increments will return a value equivalent to false until reset() is
     called.

Persistence
     None

Examples
              #include<rw/tphdict.h>



              #include<iostream.h>
          #include<rw/cstring.h>
          struct silly_h{
             unsigned long operator()(RWCString x) const
               { return x.length() * (long)x(0); }
          };
          int main(){
             RWTPtrHashMap
               <RWCString,int,silly_h,equal_to<RWCString> > age;
             RWTPtrHashMapIterator
               <RWCString,int,silly_h,equal_to<RWCString> > itr(age);
             age.insert(new RWCString("John"),new int(30));
             age.insert(new RWCString("Steve"),new int(17));
             age.insert(new RWCString("Mark"),new int(24));
          //Duplicate insertion is rejected
             age.insert(new RWCString("Steve"),new int(24));
             for(;++itr;)
               cout << *itr.key() << "'s age is " << *itr.value() << endl;
             return 0;
          }
          Program Output (not necessarily in this order)
          John's age is 30
          Mark's age is 24

Public Constructors
     Steve's age is 17



              RWTPtrHashMapIterator<K,T,H,EQ>(RWTPtrHashMap<K,T,H,EQ>&h);


     Creates an iterator for the hashed map h.  The iterator begins in an
     undefined state and must be advanced before the first element will be
     accessible.

Public Member Operators
              K*
          operator()();


     Advances self to the next element, dereferences the resulting iterator
     and returns its key.  If the iterator has advanced past the last item in
     the container,  the element returned will be a nil pointer equivalent to
     boolean false.

              RWBoolean
          operator++();


     Advances self to the next element.  If the iterator has been reset or
     just created self will now reference the first element.  If, before
     iteration, self referenced the last association in the multi-map, self
     will now reference an undefined value and a value equivalent to false
     will be returned.  Otherwise, a value equivalent to true is returned.
     Note: no post-increment operator is provided.

Public Member Functions
              RWTPtrHashMap<K,T,H,EQ>*
          container() const;


     Returns a pointer to the collection being iterated over.

              K*
          key() const;


     Returns the key portion of the association currently referenced by self.
     Undefined if self is not referencing a value within the map.

              void
          reset();
          void
          reset(RWTPtrHashMap<K,T,H,EQ>& h);


     Resets the iterator so that after being advanced it will reference the
     first element of the collection.  Using reset() with no argument will
     reset the iterator on the current container.  Supplying a hashed map with
     reset() will reset the iterator on that container.

              T*
          value();


     Returns the value portion of the association pointed to by self.  The
     behavior is undefined if the map is empty.