Re: prd refraction

The variables of the rule instance includes ?X but excludes ?C because
?C is existentially quantified.
Therefore, the "old" rule instance and the "new" rule instance are
exactly the same (same binding for ?X), and
by the refraction rule:

Refraction rule: if ri ∈ cs and lastPicked(ri, s) < recency(ri, s),
then cs = cs - ri;

lastPicked is 1 and recency is 2 and therefore the new rule instance
ri is removed from consideration.

On Mon, Jul 20, 2009 at 5:41 PM, Sandro Hawke<sandro@w3.org> wrote:
>
> As part of ACTION-851, I'm looking at:
>
> http://www.w3.org/2005/rules/wiki/Modify_noloop
>
> and trying to understand how, as per the comments, refraction (PRD
> section 4.2.4) prevents the loop from happening.  Can you walk me
> through it?  It seems to me that once the rule fires once, a new rule
> instance is available, and I don't see how that new instance is not
> fireable.
>
>    -- Sandro
>
>



-- 
Cheers,

Gary Hallmark

Received on Tuesday, 21 July 2009 04:35:46 UTC