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From: Michael Fawcett (michael.fawcett_at_[hidden])
Date: 2006-10-31 11:19:12

On 10/31/06, Martin Bonner <martin.bonner_at_[hidden]> wrote:
> > On 10/30/06, Jason Hise <0xchaos_at_[hidden]> wrote:
> >> Actually, I wonder if it is even valid to say
> >> that this container supports random access... although it supports
> >> the syntax for it, isn't random access defined as being constant
> >> time?
> >
> From: Michael Fawcett
> > I don't think so. I'm pretty sure RandomAccess only means that the
> > iterator supports the required arithmetic syntax, i.e. ++iter, iter++,
> > iter + n, iter += n. I am by no means an iterator guru.
> Sorry. Jason is right. Section 24.1 paragraph 8 of the standard:
> All the categories of iterators require only those functions that
> are realizable for a given category in constant time (amortized).
> (If there weren't a constant time requirement, there would be no point
> in distinguishing bi-directional iterators from random access iterators.
> bi-directional iterators can always implement += n by repeated
> increment.)

Thanks for the clarification, it makes perfect sense. That neatly
removes all "random access" suggestions from the name list. =)

--Michael Fawcett

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