Re: [rules-users] New Operators

Ahmed, Drools Fusion is an extension to Drools Expert. Everything you can do in Drools Expert, is also available in Drools Fusion. Please take a look at the Drools Expert manual: http://www.jboss.org/drools/documentation.html Regarding your questions: rule xyz when $a : Event( ) or $b : Event( ) then // ... end As I mentioned in my previous e-mail. Drools is FOL complete, so you can nest your constraints as you like. Assuming a,b,c,d and e are patterns: rule Exp when (A(...) and B(...) and C(...)) or (D(...) and E(...)) then // ... end rule a when B(...) and (not(B(...))) // this will only be true if constraints inside b are not the same, obviously then // ... end []s Edson 2009/8/26 Ahmed Hafsi <hafsi(a)fzi.de&gt; -- Edson Tirelli JBoss Drools Core Development JBoss by Red Hat @ www.jboss.com