David Abrahams <dave@boost-consulting.com> writes:
For Forward, Bidi and Random-access Iterators, it returns a reference to a value held in the iterator.
I'm afraid those aren't conforming forward iterators :(
24.1.3:
"If a and b are both dereferenceable, then a == b if and only if *a and *b are the same object. "
Which is why we have to change counting_iterator to not be a forward iterator.
Darn. I missed that requirement --- I was working off table 74, which just requires *a==*b if a==b (amusingly adding a requirement that the value type supports operator== in the process). This requirement makes it actually impossible to make an aggregating iterator anything other than an input or output iterator. :( On the plus side, my tuple iterator works with std::sort on every compiler I've tested it on. Do you know of any implementations that depend on this requirement being met for any of the standard algorithms? Maybe your effort on the new iterator categories can help with the problem? Anthony -- Anthony Williams Senior Software Engineer, Beran Instruments Ltd.