The long-running debate between the people like yourself, who are surprised when rules fire during a query, and those who want a query to trigger backward chaining, and so are surprised if they don't, has been resolved -- and I think you could say that you won! In recent versions of Jess 6.1 (which is at RC1 right now, and if all goes well will be in final release by the end of this week) the default is for rules to NOT fire during a query, but there's now a way to let rules fire during a query on a case-by-case basis.
So what I would do, if I were you, would be to upgrade to 6.1RC1 and things will behave by default just the way you'd like them to. I think =?iso-8859-1?q?un=20ethix?= wrote: [Charset iso-8859-1 unsupported, filtering to ASCII...] > > Hi, > Thanks for taking the time to read this. > I have a number of activated rules. The first of these rules to fire includes a > function call which includes a query iteration. However, the subsequent rules in the > conflict set (i.e. the subsequent activated rules) fire before the query call > completes. This behavior is best illustrated by an example: > Jess> (run 1) > > FIRE 1 MAIN::rule_1 f-6 > > ==> f-7 (MAIN::__query-trigger-myQuery) > > FIRE 1 MAIN::rule_2 f-5, f-6 > > If the firing is left to run then the query will eventually return > <== f-7 (MAIN::__query-trigger-myQuery) > but only after all other activated rules have fired. > My problem is that rule_2 depends upon the result of firing rule_1, and causes an > illegal operation (division by 0) as a result of rule_1 not returning first. > > I am able to circumvent this by having an extra fact asserted by rule_1, which > rule_2 needs i.e. : > (defrule rule_1 .... => > (callQuery) (assert (foo))) > (defrule rule_2 ... (foo) => ...) > In this case, since rule_2 can only be activated after the query has returned, it > works...it does seem an illogical way of doing things though. > The release notes do mention something about the run-query command executing > 'run(10)' - but this does not explain why subsequent rules don't fire after the > query returns. > Is there something that i'm missing here? > Thanks in advance, > Pol > > > > > --------------------------------- > Yahoo! Mail - For a better Internet experience --------------------------------------------------------- Ernest Friedman-Hill Distributed Systems Research Phone: (925) 294-2154 Sandia National Labs FAX: (925) 294-2234 PO Box 969, MS 9012 [EMAIL PROTECTED] Livermore, CA 94550 http://herzberg.ca.sandia.gov -------------------------------------------------------------------- To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' in the BODY of a message to [EMAIL PROTECTED], NOT to the list (use your own address!) List problems? Notify [EMAIL PROTECTED] --------------------------------------------------------------------
