From: Jost, Andrew (Andrew_Jost_at_[hidden])
Date: 2005-07-11 08:45:37
> -----Original Message-----
> From: boost-bounces_at_[hidden]
> [mailto:boost-bounces_at_[hidden]] On Behalf Of David Abrahams
> Sent: Monday, July 11, 2005 8:50 PM
> To: boost_at_[hidden]
> Subject: Re: [boost] New Library Proposal: dual_state
>
> "Jost, Andrew" <Andrew_Jost_at_[hidden]> writes:
>
> > > -----Original Message-----
> >> From: boost-bounces_at_[hidden]
> >> [mailto:boost-bounces_at_[hidden]] On Behalf Of David Abrahams
> >> Sent: Sunday, July 10, 2005 10:23 PM
> >> To: boost_at_[hidden]
> >> Subject: Re: [boost] New Library Proposal: dual_state
> >>
> >> Eelis van der Weegen <gmane_at_[hidden]> writes:
> >>
> >> > So, in conclusion, the motivation for your dual_state is
> >> very valid,
> >> > but personally I think Boost.Optional is a more
> appropriate design.
> >>
> >> IMO the "guaranteed object delivery" feature makes for a useful
> >> specialization of the Boost.Optional design. However, it would be
> >> nice to have both; it's not an alternative to Boost.Optional.
> >
> > I agree. These are two separate ideas, each with its own utility.
> >
> >>
> >> There's a lot of resonance with the Boost.Parameter
> library in here.
> >
> > Where can I find information on Boost.Parameter?
>
> In the CVS at libs/parameter (new docs in progress at
> libs/parameter/doc) and boost/parameter. An earlier version
> of the tutorial docs are at
> http://cvs.sourceforge.net/viewcvs.py/*checkout*/boost-sandbox
> /boost-sandbox/libs/utility/doc/named_params.html#tutorial
Thanks, I found it. What a great idea!
>
> > One additional thought occurred to me. How does
> Boost.Optional handle
> > cases where object construction fails? I'm not sure how many
> > approaches exist to the problem of failed constructors, but I think
> > most programmers agree that constructors should rarely (if ever) be
> > allowed to throw an exception.
>
> No, that's approximately 180 degrees away from correct.
> Bjarne Stroustrup used to recommend it, and it appears that a
> few people still think it makes sense, but in fact throwing
> from constructors is a very good idea because it allows us to
> establish simple class invariants.
>
Based on several replies, my perception was obviouly outdated.
> --
> Dave Abrahams
> Boost Consulting
> www.boost-consulting.com
>
> _______________________________________________
> Unsubscribe & other changes:
> http://listarchives.boost.org/mailman/listinfo.cgi/boost
>