Beautiful! How would a business user (non-programmer) write such a rule.

condition

------------------------------ * From: *Wolfgang Laun [wolfgang.laun(a)gmail.com] * Sent: *02/09/2012 05:02 PM CET * To: *Rules Users List <rules-users(a)lists.jboss.org&gt; * Subject: *Re: [rules-users] How do I write a rule to detect a missing value in a group of facts? Don't think procedurally, just write the *rule* for a missing post ;-) rule "missing fence post" when FencePost( $d: distanceFromStart ) FencePost( distanceFromStart == $d + 2*FencePost.GAP ) not FencePost( distanceFromStart == $d + FencePost.GAP ) then System.out.println( "Missing: " + ($d + FencePost.GAP) ); end -W On 9 February 2012 16:41, mikeg <mike(a)thegoldners.com&gt; wrote: > I need to write a rule to identify a missing element in a group of facts. > > For example, let us say I want to ensure that my fence has a fence post > every 8 feet. My fact declaration is as follows: > > declare FencePost > identifier : String > distanceFromStart: Long > end > > If I add the following facts into my session: > > FencePost("a", 0) > FencePost("x", 8) > FencePost("e", 24) > > I want a rule that will notify the user that there is a missing fence post > between "x" and "e". > > I've been looking into using "collect" into a TreeSet/TreeMap to get a > collection sorted on the "distanceFromStart", but I cannot figure out how > to > compare adjacent elements in the collection. > > Any ideas? > > -- > View this message in context: > http://drools.46999.n3.nabble.com/How-do-I-write-a-rule-to-detect-a-missi... > Sent from the Drools: User forum mailing list archive at Nabble.com. > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > ----------------------------------------- The information contained in this communication (including any attachments hereto) is confidential and is intended solely for the personal and confidential use of the individual or entity to whom it is addressed. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this communication in error and that any review, dissemination, copying, or unauthorized use of this information, or the taking of any action in reliance on the contents of this information is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail, and delete the original message. Thank you _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users ----------------------------------------- The information contained in this communication (including any attachments hereto) is confidential and is intended solely for the personal and confidential use of the individual or entity to whom it is addressed. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this communication in error and that any review, dissemination, copying, or unauthorized use of this information, or the taking of any action in reliance on the contents of this information is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail, and delete the original message. Thank you _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users