Thank you. I understand it now: In the 2nd rule: modify($p) => evaluate the 2nd rule again => re-iterate $p.address with "from", so that Drools engine can know if there is any change in $p.address compared with previous evaluation.
Also, the above modify($p) also triggers evaluation of the 1st rule. Then, why "when the second rule fires, it deactivates the first rule." as the document says? I think nobody modifies $p.address.state. So the existing activation for the 1st rule should still hold. Why the 1st rule is not fired? -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/Why-Using-from-Always-Return-A-New-Fact-tp2286393p2286492.html Sent from the Drools - User mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users
