What's the purpose of CLEANUP rule in mab-clos.lisp example?

Paolo Amoroso <[email protected]> Fri, 06 May 2005 20:48:46 +0200

Newsgroups	gmane.lisp.lisa.general
Organization	Paolo Amoroso - Milano, ITALY
Message-ID	<[email protected]>

What is the purpose of the CLEANUP rule:

  ;;; Retract every object whose ancestor is an instance of MAB-FUNDAMENTAL...

  (defrule cleanup (:salience -100)
    (?fact (mab-fundamental))
    =>
    (retract ?fact))

in the mab-clos.lisp Lisa example?  Why is it necessary to retract
objects whose ancestors are instances of MAB-FUNDAMENTAL?


Paolo
-- 
Lisp Propulsion Laboratory log - http://www.paoloamoroso.it/log


-------------------------------------------------------
This SF.Net email is sponsored by: NEC IT Guy Games.
Get your fingers limbered up and give it your best shot. 4 great events, 4
opportunities to win big! Highest score wins.NEC IT Guy Games. Play to
win an NEC 61 plasma display. Visit http://www.necitguy.com/?r=20