[rules-users] Can I check if a collection contains one, and only one item of another collection

Hi, I'm getting stuck on this and I'm hoping someone can help.. I need to be able to check that a collection contains one, and only one item from another collection. Ideally, I would do something like this: a:Answer(responses contains one of ("a","b","c")); Is there a way do do this without resorting to evals or predicate expressions? (drools 4.07) Thanks, Dave -- View this message in context: http://www.nabble.com/Can-I-check-if-a-collection-contains-one%2C-and-onl... Sent from the drools - user mailing list archive at Nabble.com.