Anyone else use Please Excuse My Dear Aunt Sally? (Parentheses, Exponentiation, Multiplication, Division, Addition, Subtraction) _____ From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Edson Tirelli Sent: Wednesday, April 09, 2008 2:39 PM To: Rules Users List Subject: Re: [rules-users] Order of operations Hi Joe, It seems someone skipped the elementary math lessons at school... :( Will open a JIRA for that. []s Edson 2008/4/9 Joe White <Joe.White(a)recondotech.com <mailto:Joe.White@recondotech.com> >: I have a question regarding order of operations in the consequence of a rule when using the mvel dialect. When executed the Drl below provides Right =30.0 and Wrong =140.0. The only difference is the parens around the multiplying expressions, which shouldn't be necessary given order of operations. Is this a problem with the drools/mvel interaction or is it completely an issue with mvel? Is the general expectation that all expressions must be completely scoped by parens when using mvel? package test; dialect "mvel" rule "test 11" when then double rightVal=((10-5)*2) + (5*(8-4)); double wrongVal=(10-5)*2 + 5*(8-4); System.out.println("Right ="+rightVal); System.out.println("Wrong ="+wrongVal); End After execution: Right =30.0 Wrong =140.0 Thank you for all of your help. We are using drools 4.0.4. <http://4.0.4.> Joe Also, I haven't figured out how it arrives at 140. The following format also produces 140, which seems a little more strange. double wrongVal=10-5*2 + 5*8-4; _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org <mailto:rules-users@lists.jboss.org> https://lists.jboss.org/mailman/listinfo/rules-users <https://lists.jboss.org/mailman/listinfo/rules-users> -- Edson Tirelli JBoss Drools Core Development Office: +55 11 3529-6000 Mobile: +55 11 9287-5646 JBoss, a division of Red Hat @ www.jboss.com <http://www.jboss.com>