I have the basics to backward chaining working now, using both named and positional arguments and mix of both. Mixed positional/named syntax is based conceptually on the RuleML proposal for POSL: http://ruleml.org/submission/ruleml-shortation.html
POSL provides a bridge between the positional terms, often used in Prolog, and "slotted" names used in OO languages. POSL allows the best of both worlds. I'm building out the tests, which should illustrate the behaviour and syntax here: https://github.com/droolsjbpm/drools/tree/master/drools-compiler/src/test/java/org/drools/integrationtests/BackwardChainingTest.java Still lots to do to improve the over all syntax and consistency across patterns. The last test is a geneology style test which is probably more intesting to people. There is still an issue here when using eval. I currently use "new Variable" to indicate an unbound unification variable, the problem is that evals and other things generate code expecting the original object type, say "String" and this results a cast error (see sibling rule). I want to avoid an explicit instanceof check for unwrapping and will be working on that over the weekend. There is enough there now to give people an idea of what it looks like. I'll try and put together a "roadmap" for BC, along with more details of the syntax next week once it all comes together. If anyone wants to help on this, you know where to fine me :) irc.codehaus.org #drools Mark _______________________________________________ rules-dev mailing list rules-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev
