RWTPtrHashSetIterator(3C++) RWTPtrHashSetIterator(3C++)
Name
RWTPtrHashSetIterator<T,H,EQ> - Rogue Wave library class
Synopsis
#include<rw/tphset.h>
RWTPtrHashSet<T,H,EQ> m;
RWTPtrHashSet<T,H,EQ> itr(m);
Please Note!
If you have the Standard C++ Library, use the interface described here.
Otherwise, use the restricted interface to RWTPtrHashTableIterator
described in Appendix A.
DescriptionRWTPtrHashSetIterator 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 RWTPtrHashSet 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 pre-increment or an 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/tphset.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(){
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RWTPtrHashSetIterator(3C++) RWTPtrHashSetIterator(3C++)
RWTPtrHashSet <RWCString,silly_h,equal_to<RWCString> > age;
RWTPtrHashSetIterator
<RWCString,silly_h,equal_to<RWCString> > itr(age);
age.insert(new RWCString("John"));
age.insert(new RWCString("Steve"));
age.insert(new RWCString("Mark"));
//Duplicate insertion is rejected
age.insert(new RWCString("Steve"));
for(;++itr;) cout << *itr.key() << endl;
return 0;
}
Program Output (not necessarily in this order)
John
Mark
Steve
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RWTPtrHashSetIterator(3C++) RWTPtrHashSetIterator(3C++)
Public Constructors
RWTPtrHashSetIterator<T,H,EQ>(RWTPtrHashSet<T,H,EQ>&h);
Creates an iterator for the hashed 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 multi-map, self
will now point to 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
RWTPtrHashSet<T,H,EQ>*
container() const;
Returns a pointer to the collection being iterated over.
T*
key() const;
Returns the element referenced by self. Undefined if self is not
referencing a value within the set.
void
reset();
void
reset(RWTPtrHashSet<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 RWTPtrHashSet
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RWTPtrHashSetIterator(3C++) RWTPtrHashSetIterator(3C++)
to reset() will reset the iterator on that container.
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