Re: [boost] Deterimining interest in: Optional Polymorphic Value object with Small Object optimization

From: Corrado Zoccolo (czoccolo_at_[hidden])
Date: 2007-10-21 03:10:03

On 10/20/07, Corrado Zoccolo <czoccolo_at_[hidden]> wrote:
>
>
> On 10/20/07, Sebastian Redl <sebastian.redl_at_[hidden]> wrote:
> >
> > So, is this more a boost::any with SBO or a boost::optional that can
> > store polymorphic types if necessary?
>
>
> I haven't looked at boost::any implementation yet, but I guess it is based
> on the same recipe as boost::function, so I think that what you need can be
> implemented easily with optional_poly as a basic tool.
>
>
> It seems to me like it is the latter. That sounds useful, but right now
> > I'd need the former.
>
>
> I will work on some sample code to show how it can be obtained, and come
> back.
>

It was actually pretty easy. boost::any used plain dynamic polymorphism
through a pointer, so it was only matter of changing this pointer with an
optional_poly, and remove some of the ad-hoc code for cloning (achieved
automatically with optional_poly).
This gives you a boost::any with small object optimization, and shows the
potential usefulness of optional_poly as a basic tool to implement higher
abstractions with low penalties.

I posted this example, as well as the other big example in the vault (*
http://tinyurl.com/2rfaah*).

Corrado
>
>
> Sebastian Redl
> > _______________________________________________
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> >
>
>
>
> --
> __________________________________________________________________________
>
>
> dott. Corrado Zoccolo                          mailto:zoccolo_at_[hidden]
> PhD - Department of Computer Science - University of Pisa, Italy
> --------------------------------------------------------------------------
>
>
>
>

-- 
__________________________________________________________________________
dott. Corrado Zoccolo                          mailto:zoccolo_at_[hidden]
PhD - Department of Computer Science - University of Pisa, Italy
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