RWTPtrHashMultiSetIterator(3C++) RWTPtrHashMultiSetIterator(3C++)
Name
RWTPtrHashMultiSetIterator<T,H,EQ> - Rogue Wave library class
Synopsis
#include<rw/tphasht.h>
RWTPtrHashMultiSet<T,H,EQ> m;
RWTPtrHashMultiSet<T,H,EQ> itr(m);
Please Note!
If you have the Standard C++ Library, use the interface described here.
Otherwise, use the interface for RWTPtrHashTableIterator described in
Appendix A.
DescriptionRWTPtrHashMultiSetIterator 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 RWTPtrHashMultiSet 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
all 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()
operation. 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
Examples
#include<rw/tphasht.h>
#include<iostream.h>
#include<rw/cstring.h>
struct silly_h{
unsigned long operator()(RWCString x) const
{ return x.length() * (long)x(0); }
};
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RWTPtrHashMultiSetIterator(3C++) RWTPtrHashMultiSetIterator(3C++)
int main(){
RWTPtrHashMultiSet<RWCString,silly_h,equal_to<RWCString> > age;
RWTPtrHashMultiSetIterator
<RWCString,silly_h,equal_to<RWCString> > itr(age);
age.insert(new RWCString("John"));
age.insert(new RWCString("Steve"));
age.insert(new RWCString("Mark"));
age.insert(new RWCString("Steve"));
for(;++itr;)
cout << *itr.key() << endl;
return 0;
}
Program Output (not necessarily in this order)
John
Mark
Steve
Public Constructors
Steve
RWTPtrHashMultiSetIterator<T,H,EQ>
(RWTPtrHashMultiSet<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
T*
operator()();
Advances self to the next element, dereferences the resulting iterator
and returns its value. 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 multiset, self
will now reference an undefined value and a value equivalent to false
will be returned. Otherwise, a value equivalent to true is returned.
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RWTPtrHashMultiSetIterator(3C++) RWTPtrHashMultiSetIterator(3C++)
Note: no post-increment operator is provided.
Public Member Functions
RWTPtrHashMultiSet<T,H,EQ>*
container() const;
Returns a pointer to the collection being iterated over.
T*
key() const;
Returns the value currently referenced by self. Undefined if self is not
referencing a value within the multiset.
void
reset();
void
reset(RWTPtrHashMultiSet<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
RWTPtrHashMultiSet to reset() will reset the iterator on that container.
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