Prolog and C questions

[Gerard Palma]

Hi Guys 

I have not grasped how Prolog and C interface yet.

It sounds either extremely complicated task for the programmer, or am i 
missing somethting. 
Variables in Prolog are different from that of C, in C you have to declare
them as a type, but in prolog they can be different things at different times. 

So how do you pass through variables from prolog to a C function?
How do you get the return value?

I would be very interested if someone could put some more light on this
subject.

Regards

Gerard














On Wed, 13 Jun 2001, Leonardo B. Lopes wrote:

> I like this tutorial:
> 
> 
> http://www.csupomona.edu/~jrfisher/www/prolog_tutorial/pt_framer.html
> 
> although it may be more advanced than what you are looking for. As for the
> specific question you asked, apparently, the clause homem/1 is not defined
> in your code, but is being specified as part of the man/1 clause. If you
> don't understand what I just said, then you probably need to go back to a
> good prolog book and read the first chapter. "The Art of Prolog" is always
> a top candidate...
> 
> Good Luck!
> Leo.
> 
> 
> On Wed, 13 Jun 2001, Tiago Sant' Anna da Silva wrote:
> 
> > Hi,
> > Could, please somebody tell me why I can't do anything in this program?
> > This is my fist time, I've never used this program before, just at 
> > classroom, 
> > in theoric way.
> > Is there a place with a tutorial, about syntax.
> > 
> > this is an error I got:
> > | ?- men(tiago).
> > uncaught exception: error(existence_error(procedure,homem/1),top_level/0)
> > 
> > why?
> > 
> > Thank's
> > 
> > -- 
> > |===|===|===|===|===|===|===|===|===|===|===|===|===|
> > 
> > -~^''"''^~-~^? => Tiago Sant' Anna da Silva
> >     address@hidden
> > 
> > Linux user #136940
> > Get counted at http://counter.li.org
> > 
> > ICQ: 14252973
> > 
> > |===|===|===|===|===|===|===|===|===|===|===|===|===|
> > 
> > _______________________________________________
> > Users-prolog mailing list
> > address@hidden
> > http://mail.gnu.org/mailman/listinfo/users-prolog
> > 
> 
> ========================================================================
> Leonardo B. Lopes                                       address@hidden 
> Ph.D. Student                                              (847)491-8470
> IEMS - Northwestern University              http://www.iems.nwu.edu/~leo
> 
> 
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> 

Gerard Palma       
Support Engineer
3Glab
Tel: 01223478922
email: address@hidden