You have the answer in your example, reserved word "contains" will give you that information.

Scott Burrows

On Sat, Aug 23, 2008 at 9:23 AM, David Cracauer <> wrote:

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)


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