Re: [Boost-users] A forward iterator need not be default-constructible

Subject: Re: [Boost-users] A forward iterator need not be default-constructible
From: Brian Allison (brian.w.allison_at_[hidden])
Date: 2011-09-30 12:35:00

On Fri, Sep 30, 2011 at 12:29 PM, Andrew Sutton <asutton.list_at_[hidden]>wrote:

> >> Actually, every iterator (singular, initialized, pointing to viable
> >> memory or not) defines its own empty range.
> >
> > No, I don't believe that's quite correct.  There are lots of things one
> > can do with iterators in a range that one cannot do with a
> > minimally-singular iterator.
>
> Well, two anyways: == and !=. Given that the standard doesn't allow
> those on singular-valued iterators, you're right. I think the standard
> is a little too strict, here.
>
>
>
More than that, you can't do any comparisons, and the only mutation is to
set it to a Non-Singular value.