Re: [boost] [MPL] Compile-time math metafunctions.

From: Cromwell Enage (sponage_at_[hidden])
Date: 2004-05-16 18:56:15

--- David Abrahams <dave_at_[hidden]> wrote:
> Did you compile it?  If so, on what compilers?

My main development compiler is MinGW 3.2; I haven't
actually tested it on MSVC 6.

> I can't see how it could possibly work.

I just read that not all compilers support inline
initialisation of member constants.  Arrgh!

>   #include <boost/config.hpp>
> 
>   template <typename RealNum>
>   struct sample_t
>   {
>       BOOST_STATIC_CONSTANT(RealNum, base  = 5.0);
>       BOOST_STATIC_CONSTANT(RealNum, power = 1.0);
>       BOOST_STATIC_CONSTANT(RealNum, angle = 1.234);
>   };
> 
> is an illegal program (try comeau online to see some
> reasons why).

I was hoping BOOST_STATIC_CONSTANT would work on more
than just integral types.

> Also, it's not very mpl-ish.  Nothing seems to
> follow the metafunction protocol of operating on
> and returning types.

Oh, okay.  I'll keep this protocol in mind the next
time I try to write MPL metafunctions.  Right now, it
seems I can't directly use templates anyway for this
library.

> I hate to be discouraging; it's probably a really
> interesting idea.

No problem.  I have a need for this sort of thing
myself, so I'll definitely keep working at it.

> I am only looking as far as some details of the
> implementation, here.

I'll look into Boost.Preprocessor to see if I can
implement my functions via macros.  I'll send another
email when I have results.

                              Cromwell Enage

        
                
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