W3C home > Mailing lists > Public > public-rif-wg@w3.org > June 2009

Re: [Core](PRD] safeness

From: Gary Hallmark <gary.hallmark@oracle.com>
Date: Wed, 10 Jun 2009 09:47:28 -0700
Message-ID: <499257640906100947n3f9868d4rddd8bceb07001f1f@mail.gmail.com>
To: Christian De Sainte Marie <csma@fr.ibm.com>
Cc: RIF <public-rif-wg@w3.org>
In production rule systems such as CLIPS and Jess (and JRules, too, I
think), if a rule such as

if P then Q

is safe, and if Q references no variables in P, then

if not(P) then Q

is also safe.

I will not be happy with a PRD safeness definition that does not
properly account for this.

On Wed, Jun 10, 2009 at 2:03 AM, Christian De Sainte
Marie<csma@fr.ibm.com> wrote:
>
> ********* NOTICE **********
> My new email address at IBM is: csma@fr.ibm.com
> My ILOG email address will not be forwarded after June 8
> *****************************
>
>
> Gary Hallmark <gary.hallmark@oracle.com> wrote on 09/06/2009 22:54:27:
>>
>> R1: if not(P(?x) and ?x=1) then Q(1)
>>
>> I claim R1 is safe because ?x is bounded and used only "inside the not".
>
> No, R1 is not safe either, I think; because x can be bound to anything (any
> x!=1 satisfies the condition, independent of P).
>
> Christian
>
>
> ILOG, an IBM Company
> 9 rue de Verdun
> 94253 - Gentilly cedex - FRANCE
> Tel. +33 1 49 08 35 00
> Fax +33 1 49 08 35 10
>
>
>
> Sauf indication contraire ci-dessus:/ Unless stated otherwise above:
> Compagnie IBM France
> Siège Social : Tour Descartes, 2, avenue Gambetta, La Défense 5, 92400
> Courbevoie
> RCS Nanterre 552 118 465
> Forme Sociale : S.A.S.
> Capital Social : 609.751.783,30 €
> SIREN/SIRET : 552 118 465 02430
>
>



-- 
Cheers,

Gary Hallmark
Received on Wednesday, 10 June 2009 16:48:06 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 10 June 2009 16:48:06 GMT