[boost] Re: [utility] question on prior(x,n)

From: Daniel Frey (daniel.frey_at_[hidden])
Date: 2004-02-25 05:27:21

David Abrahams wrote:
> Daniel Frey <daniel.frey_at_[hidden]> writes:
> 
>>Providing the implementation for next/prior in the documentation might
>>be sufficient for the one-argument-version, but for the two argument
>>version it's quite hard to help getting the implementation bug-free if
>>I don't know what you intended. Can you write down original intent,
>>please?
> 
> Well, you came up with the 2-arg version.

That was Daniel Wallin (too many Daniels error?). I guess this also 
explains why I had the feeling we were talking past each other a bit :)

> I can only say that the
> original intent of the 1-arg versions was to operate on anything
> supporting prefix ++/--, respectively.  If the 2-arg version won't do
> that, I guess we should change the name.

OK, I understand now that I have to distinguish the 1-arg version from 
the 2-arg version.

> Incidentally, it's almost always possible to detect whether the first
> argument supports operator += or operator-=.  That might be a good way
> to decide whether to advance/regress it.

If is_iterator yields false, this is good to distinguish the rest, yes. 
But the first question is, whether we want to enhance the 2-arg version 
of next/prior or if we simply rename them to e.g. advanced/regressed. 
I'd be happy with the latter. Comments?

Regards, Daniel

-- 
Daniel Frey
aixigo AG - financial solutions & technology
Schloß-Rahe-Straße 15, 52072 Aachen, Germany
fon: [phone], fax: [phone]
eMail: daniel.frey_at_[hidden], web: http://www.aixigo.de