Re: [boost] Request For a feature - Templated virtual functions

Subject: Re: [boost] Request For a feature - Templated virtual functions
From: Gokulakannan Somasundaram (gokul007_at_[hidden])
Date: 2009-02-12 07:56:30

On Thu, Feb 12, 2009 at 6:13 PM, vicente.botet <vicente.botet_at_[hidden]>wrote:

> ----- Original Message -----
> From: "Gokulakannan Somasundaram" <gokul007_at_[hidden]>
> To: <boost_at_[hidden]>
> Sent: Thursday, February 12, 2009 1:33 PM
> Subject: Re: [boost] Request For a feature - Templated virtual functions
>
>
> >
> > On Thu, Feb 12, 2009 at 4:00 PM, Mathias Gaunard <
> > mathias.gaunard_at_[hidden]> wrote:
> >
> >> Gokulakannan Somasundaram wrote:
> >>
> >>  Thanks for pointing me to Boost.Variant. But let me just try to clarify
> my
> >>> understanding on Boost Variant. It is a kind of union data type, where
> we
> >>> store the data and its type together. Whenever we retrieve the data, it
> >>> does
> >>> a switch-case lookup and type-casts the data to that type. In my
> opinion,
> >>> the switch-case is equivalent to a virtual table lookup. They should be
> >>> having more or less the same runtime penalty.
> >>>
> >>
> >> Indeed.
> >> A switch-case is actually faster than a virtual table lookup, however.
> >>
> >>
> >> I did a small test in my system and the virtual function method proved
> to
> > be slightly better than using boost::variant. The difference can be
> ignored,
> > but then there is no use in switching to boost::variant. The method i
> > suggest is simple, it just replaces the virtual function overloading with
> > templates and hence it would provide better performance and better
> > maintenance.
>
> Hi,
>
> I'm interested.
>
> Could you show more :)
> Best,
> Vicente
>

Hi,
   Sorry! I don't get you.  i have just made a feature request, to allow
templates in virtual functions, if  the knowledge of the classes involved is
known at Compile time and waiting for someone to take up my request :)

Thanks,
Gokul.