Re: beginner question (SOLVED)

[Luca Ciciriello]

Yes, you are right.  I haven't noticed the warning.
I've made contiguous the statements. All solved.

Thanks.

Luca.
On May 9, 2010, at 5:54 PM, Sylvain Soliman wrote:

> * Luca Ciciriello <address@hidden>:
>> I've created the file test2.pl with the following content:
>> 
>> listensToMusic(mia). 
>> happy(yolanda). 
>> playsAirGuitar(mia) :- listensToMusic(mia). 
>> playsAirGuitar(yolanda) :- listensToMusic(yolanda). 
>> listensToMusic(yolanda):- happy(yolanda).
>> 
>> and I've loaded it in to interpreter typing [test2].
> 
> And you have seen a warning message:
> "test2.pl:5: warning: discontiguous predicate listensToMusic/1 - clause
> ignored"
> 
>> now the book is telling me that if I type at the prompt the query:
>> 
>> ?- playsAirGuitar(yolanda).
>> 
>> the result i obtain is "yes".
>> 
>> My problem is that the result I obtain is a big "no".
>> 
>> Now, as student, I'm a bit confused.
>> Who is right and who is wrong?
>> The book or the interpreter?
> 
> Hmmm... both!
> 
> GNU Prolog does not allow discontiguous predicates (and told you so!), so
> "no" is correct... However the book is correct "in general", and if you
> make the two clauses of listenToMusic contiguous (just one after the other)
> it will work.
> 
> Best,
> 
>        Sylvain.
> 
> -- 
> Sylvain Soliman <address@hidden>         Tel: (+33) 1 39635761
> INRIA Paris-Rocquencourt - Equipe CONTRAINTES      Fax: (+33) 1 39635469
> Domaine de Voluceau, Rocquencourt, BP 105   GnuPG Public Key: 0x0F53AF99
> 78153 LE CHESNAY CEDEX - FRANCE    http://contraintes.inria.fr/~soliman/
> _______________________________________________
> Users-prolog mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/users-prolog