From: David Abrahams (dave_at_[hidden])
Date: 2002-10-13 22:53:34
"Victor A. Wagner, Jr." <vawjr_at_[hidden]> writes:
> At Sunday 2002/10/13 16:39, you wrote:
> >"Terje Slettebø" <tslettebo_at_[hidden]> wrote in message
> > >From: "Yitzhak Sapir" <yitzhaks_at_[hidden]>
> > >On Sun, 13 Oct 2002, [iso-8859-1] Terje Slettebø wrote:
> > >As I understand, the only thing you can safely do with an end() iterator is
> > >to compare it with other iterators.
> > If operator-- is defined on an iterator, and begin() != end(), then it is
> >also safe to decrement an iterator that is equal to end().
> >reverse_iterators depend on this fact. This is why rbegin().base() ==
> I don't see how that follows. I agree that rbegin().base() == end(),
> but don't see how that implies that ANY operations on end() are legal.
Well, nothing needs to allow operations on end(), because nothing
forbids it. In general, the rule is: if the standard doesn't forbid
it, it is allowed.
That aside, the implementation of reverse_iterator is clearly spelled
out in the standard:
1 Effects: --current;
So, Terje's argument holds water.
-- David Abrahams * Boost Consulting dave_at_[hidden] * http://www.boost-consulting.com
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