RWTValHashMultiSetIterator(3C++) RWTValHashMultiSetIterator(3C++)
Name
RWTValHashMultiSetIterator<T,H,EQ> - Rogue Wave library class
Synopsis
#include<rw/tvhasht.h>
RWTValHashMultiSet<T,H,EQ> m;
RWTValHashMultiSet<T,H,EQ> itr(m);
Please Note!
If you have the Standard C++ Library, use the interface described here.
Otherwise, use the interface for RWTValHashTableIterator described in
Appendix A.
DescriptionRWTValHashMultiSetIterator is supplied with Tools.h++ 7 to provide an
iterator interface to RWTValHashMultiSetIterator that is backward
compatible with the container iterators provided in Tools.h++ 6.x.
Iteration over an RWTValHashMultiSet is pseudorandom and dependent on the
capacity of the underlying hash table and the hash function being used.
The only useable relationship between consecutive elements is that
elements which are defined to be equivalent by the equivalence object,
EQ, will remain adjacent. 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. Continued
increments will return a value equivalent to false until reset() is
called.
Persistence
None
Example
#include<rw/tvhasht.h>
#include<iostream.h>
#include<rw/cstring.h>
struct silly_h{
unsigned long operator()(const RWCString& x) const
{ return x.length() * (long)x(0); }
};
int main(){
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RWTValHashMultiSetIterator(3C++) RWTValHashMultiSetIterator(3C++)
RWTValHashMultiSet
<RWCString, silly_h,equal_to<RWCString> > age;
RWTValHashMultiSetIterator
<RWCString, silly_h, equal_to<RWCString > > itr(age);
age.insert("John");
age.insert("Steve");
age.insert("Mark");
age.insert("Steve");
for(;itr();)
cout << itr.key() << endl;
return 0;
}
Program Output (not necessarily in this order)
John
Steve
Mark
Steve
Public Constructors
RWTValHashMultiSetIterator<T,H,EQ> (RWTValHashMultiSet<T,H,EQ>&h);
Creates an iterator for the hashed multi-set h. The iterator begins in
an undefined state and must be advanced before the first element will be
accessible
Public Member Operators
RWBoolean
operator()();
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RWTValHashMultiSetIterator(3C++) RWTValHashMultiSetIterator(3C++)
Advances self to the next element. Returns false if the iterator has
advanced past the last item in the container and true otherwise.
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 value in the multi-set, self will now
reference an undefined value and false will be returned. Otherwise, true
is returned. Note: no postincrement operator is provided.
Public Member Functions
RWTValHashMultiSet<T,H,EQ>*
container() const;
Returns a pointer to the collection being iterated over.
T
key() const;
Returns the value currently referenced by self.
void
reset();
void
reset(RWTValHashMultiSet<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
RWTValHashMultiSet to reset() will reset the iterator on that container.
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