The following are not proper uses of iterators, but may be working
fixes for existing uses of iterators.
you cannot do
ostream::operator<<(iterator) to
print the address of the iterator => use
operator<< &*iterator instead ?
you cannot clear an iterator's reference
(iterator = 0) => use
iterator = iterator_type(); ?
if (iterator) won't work any
more => use if (iterator != iterator_type())
?
