I think Doug Metzler wrote: > One issue that I noticed with Jess is that it apparently has only > depth first and breadth first conflict resolution. I found that odd > since it has been my impression that the vast majority of programs > written in OPS, Clips, etc. over the years have used MEA or > LEX... Do most people using Jess write their own CR strategies or > does the Jess community find recency/specificity (and goal based) > strategies unnecessary? If the latter I'm curious why.
The Jess user community is interesting because it is comprised of several broad, distinct groups. There are (for lack of a better term) traditional ES builders; there are people working with Semantic Web technologies; and there are commercial business rule engine users (which, of late, is the largest group.) The needs of each of these groups are disjoint, and it's a great benefit to all that they exist, because the cross-pollenation is quite useful. Correct me if you disagree, but in our experience it's largely the first group that makes use of diverse conflict resolution strategies; the simple, intuitive breadth and depth strategies serve the other two groups well. We have had several requests from academic users for MEA and LEX implementations recently, and so this is on the list of things to be done. It is indeed true that neither CLIPS and OPS had documented interfaces for adding CR strategies, but Jess actually does. Recent versions have finally made the "pseudotime" property of facts and Rete tokens a public property, so writing any of these strategies is indeed something that people can and have done. The biggest barrier to writing supported implementation of MEA and LEX in the near term is the need for good test data. If you have one or more small(ish) programs which work correctly only with one of these strategies -- preferably in CLIPS syntax -- then that would be a help to us. --------------------------------------------------------- Ernest Friedman-Hill Advanced Software Research Phone: (925) 294-2154 Sandia National Labs FAX: (925) 294-2234 PO Box 969, MS 9012 [EMAIL PROTECTED] Livermore, CA 94550 http://herzberg.ca.sandia.gov -------------------------------------------------------------------- To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' in the BODY of a message to [EMAIL PROTECTED], NOT to the list (use your own address!) List problems? Notify [EMAIL PROTECTED] --------------------------------------------------------------------
