From: Andrew Koenig (ark_at_[hidden])
Date: 2002-08-23 13:22:16
>> The same argument applies to .
Peter> A weaker version of the argument. Only random access iterators
Peter> have , so users cannot expect all iterators to supply it.
Right. But they can expect random-access iterators to supply it.
Peter> Theory aside, do users really expect  from iterators? I have
Peter> never used iterator::, although I do use iterator::->
I would expect that most users of iterators do not actually require
random-access iterators. There are only three operations that
random-access iterators, and not other iterators, are required to
iter + integer (and integer + iter)
iter - iter
Either of the first two operations can substitute for the other,
so the real question is whether the second is much more common than
the first. I suspect it isn't.
-- Andrew Koenig, ark_at_[hidden], http://www.research.att.com/info/ark
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