Laboratory Exercises, C++ Programming

Programming with the STL 33
class BitsetIterator : public BitReference {
public:
// ... typedefs, see below
};
BitsetIterator(Bitset::BitsetStorage* pb, size_t p)
: BitReference(pb, p) {}
BitsetIterator& operator=(const BitsetIterator& bsi);
bool operator!=(const BitsetIterator& bsi) const;
BitsetIterator& operator++();
BitReference operator*();
The assignment operator must be redefined so it copies the member variables (as opposed to the
assignment operator in the base class BitReference, which sets a bit in the bitset). The typedefs
are necessary to make the iterator STL-compliant, i.e., to make it possible to use the iterator with
the standard STL algorithms. The only typedef that isn’t obvious is:
typedef std::forward_iterator_tag iterator_category;
This is an example of an iterator tag, and it informs the compiler that the iterator is a forward
iterator.
A5. Implement the member functions in bitsetiterator.cc. Uncomment the lines in bitset.h and
bitset.cc that have to do with iterators, implement the begin() and end() functions. Use
the program bitsettest2.cc to test your classes.