Re: [rules-users] Chart notation, update, and infinite loops

Put it in a global variable? --- On Tue, 11/4/08, Dan Seaver <dan.seaver(a)ge.com&gt; wrote: > From: Dan Seaver <dan.seaver(a)ge.com&gt; > Subject: Re: [rules-users] Chart notation, update, and infinite loops > To: rules-users(a)lists.jboss.org > Date: Tuesday, November 4, 2008, 2:08 PM > Thanks Edson, > I'm aware of "accumulate" and see how it can > be used to solve the specific > issue. > > I'm looking for a more generic solution for updating > objects. > > The only reason amountFact is part of the "when" > clause is for a reference > to the object that can be used by the "then" > clause. It's not really part of > the rule criteria. > > If I could get a reference to it directly in the > "then" clause, the update > statement would not put the rule back on the agenda - which > would be > perfect. > > Any ideas? > > Dan > > Edson Tirelli-3 wrote: > > > > There are several ways of doing that, and some > where even mentioned by > > the other users. One easy way is to simply use > "accumulate": > > > > rule "update amount" > > no-loop > > when > > $f : Fact( name == "amount" ) > > Number( $total : doubleValue ) from accumulate( > > Charge( $amt : amount ), > > sum( $amt ) ) > > then > > modify( $f ) { setAmount( $total ) } > > end > > > > []s > > Edson > > > > 2008/11/4 Dan Seaver <dan.seaver(a)ge.com&gt; > > > >> > >> I'm trying to find a good technique for > updating specific facts in > >> working > >> memory. What I'm currently doing is something > like this: > >> > >> Rule "Update Amount" > >> when > >> amountFact : Fact(name == "Amount") > >> charge : Charge() > >> then > >> Double amount = amountFact.getAmount(); > >> Double chargeAmount = charge.getAmount(); > >> amountFact.setAmount(amount + chargeAmount); > >> update(amountFact); > >> end > >> > >> The update statement causes an infinite loop. > >> I tried using no-loop, which works if there is 1 > charge, but not if there > >> are more than one. > >> > >> Any help with solutions or strategies would be > much appreciated. > >> -- > >> View this message in context: > >> > http://www.nabble.com/Chart-notation%2C-update%2C-and-infinite-loops-tp20... > >> Sent from the drools - user mailing list archive > at Nabble.com. > >> > >> _______________________________________________ > >> rules-users mailing list > >> rules-users(a)lists.jboss.org > >> > https://lists.jboss.org/mailman/listinfo/rules-users > >> > > > > > > > > -- > > Edson Tirelli > > JBoss Drools Core Development > > JBoss, a division of Red Hat @ www.jboss.com > > > > _______________________________________________ > > rules-users mailing list > > rules-users(a)lists.jboss.org > > https://lists.jboss.org/mailman/listinfo/rules-users > > > > > > -- > View this message in context: > http://www.nabble.com/Chart-notation%2C-update%2C-and-infinite-loops-tp20... > Sent from the drools - user mailing list archive at > Nabble.com. > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users