Re: strange crash after assertion with std::map::iterator

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"Mycroft Holmes" <m.holmes@xxxxxxxxx> wrote in message
news:eIVybCxhHHA.4976@xxxxxxxxxxxxxxxxxxxx
first, iterators DO contain pointers; I cannot prove it, but I'd bet
it's IMPOSSIBLE to design an iterator without making use of pointers.

Stream iterators are unlikely to contain pointers. Maybe a pointer to
the stream, but definitely not a pointer to T (T being the type of
elements iterated over).

vector::iterator could very well hold an index rather than a pointer.

I don't quite understand how this issue is relevant, though.

second, I never said that a value-initialized iterator should be the
end of anything. I just said it should be a VALID ITERATOR, and I
made clear what I mean by "valid": just equality and inequality
comparable.

Comparable to what? What should be the result of such a comparison?
Perhaps more importantly, _why_ do you want that? In what situation
would you like to be able to use such a facility?

As an aside, note that output iterators aren't required to be equality
comparable at all, singular values or otherwise (C++ standard 24.1.2,
Table 73).
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925


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