NOTE: Reposted because I only just subscribed to the mailing list. Hello, I have a set of Fact types which represent factors matched and used throughout the other rules. Each of these Fact types may be derived in a variety of mutually exclusive ways--ie based on the line of business or other factors. The rules are all well-defined for these Facts. Something like this: declare FactorType1 value : BigDecimal end rule "FactorType1" when LineOfBusiness( this == LineOfBusiness.LOB1 ) // some other conditions $prms : Params() // ***provisional*** where to specify needed context dependent parameters? see below then BigDecimal value = new BigDecimal("0"); // ... determine value based on conditions and $prms insert( new FactorType1(value) ); end // <some other mutually exclusive rules to derive FactorType1 here> The problem is that in the rules which match these Facts, there are many context dependent (ie *always* unique to that particular rule) parameters which must be "passed" to the derivation of those Facts. I'm referring to these as "Params" above. Now, a rule that uses FactorType1: rule "a rule that uses FactorType1" when // some conditions FactorType1( $value ) $prms : Params(prm1,prm2,prm3,...) // ***provisional*** how to indicate that FactorType1 should use these parameters in its derivation? then // perform some calculation with $value end The parameters which these Facts use cannot be asserted as Facts themselves. They are unique to the rules which match on the FactorTypes, so that would mean I'd need a duplicate rule for every rule that uses a FactorType (even with "rule inheritance", this is excessive). It's almost as if I need to specify a "partial derivation" or "partial unification" of the Fact type, which is only asserted once a rule indicates that it is providing the "unbound" portion of the derivation. I understand queries can be used for some sort of partial unification, but I have no clue how to apply them to my problem and I can't find any good examples or documentation on their usage/behavior. Thanks in advance -- View this message in context: http://drools.46999.n3.nabble.com/Partial-Unification-Derivation-of-Facts... 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

Let me start from scratch as I'm realizing how difficult it is to understand my issue. There is a Fact "A" with some rules use as conditions.  "A" can be derived in several different but mutually exclusive ways.  For the most part, the rules which define each of these derivations depend on states/conditions which the rules matching on "A" are largely agnostic of. rule "rule deriving A" when   //some conditions then   insert( new A(/*some values*/) ); end rule "another rule driving A" when  //some other conditions then  insert( new A(/*some other values*/) ); end // many other rules deriving A However, there are also other "parameters"/"values" needed for the computation of the many derivations of "A" (they need to be present in the RHSs of rules deriving "A").  The combination of these values are context-dependent to each matching of "A" /every time/.  That is, each matching of "A" has a unique set of values binded to a particular set of parameters expected by rules deriving "A").  Rules deriving "A" need not and should not match on these parameters because they are different for every matching of "A"; the derivations should (ideally) take on whatever values are specified in the matching. rule "rule matching on A" when  $a : A() // needs to somehow convey to the derivation of A() that it should use a set of values unique to this matching in its derivation then  // use $a end rule "another rule matching on A" when  $a : A() // needs to somehow convey to the derivation of A() that it should use a set of values unique to this matching in its derivation then  // use $a end I cannot leave it up to the rules deriving "A" to handle every single case of different values for these parameters--there would be thousands of different combinations of derivations of "A" and nobody would understand the code. The rules deriving "A" cannot match on general "Parameter" objects because the values in the Parameter objects are unique for each matching of "A". This would mean that each rule matching "A" would need a counterpart rule which asserts the parameters/values needed by the rules deriving "A".  I mean, I suppose this /is/ a solution, but it's obviously difficult to understand design. I guess what I'm looking for is something inbetween a function (with explicitly binded parameters) and a derivation that is rule based--to be able to say "derive this kind of object in any way that you can, but use these particular values in its derivation".  Perhaps this is not possible. -- View this message in context: http://drools.46999.n3.nabble.com/Partial-Unification-Derivation-of-Facts... 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

How would I go about implementing the first part to your solution? (where you say "if it is the 'matching' rule that defines the parameter set you can define the parameters literally in that rule") I am not aware of any syntax that would permit this type of behavior--that would allow me to (in the matching rule's condition) literally define the values the rules deriving "A" should use, instead of the deriving rule matching it against working memory (ie to indicate from the matching rule that the derivation rule should always use a certain value as a condition rather than matching against working memory). Given: rule "derivation rule" when   $prm1 : Param1() then  insert( new A($prm1) ); end , the following indicates that working memory should be pattern matched for an "A" with getParam1() == new Param1("val").  Of course, this is not my desired functionality: rule "matching rule 1" when   A( param1 == new Param1("val") ) then   // do w/e end What I would like to see is--given the "derivation rule" above--something like this: rule "matching rule 2" when   $a : A( param1 := new Param1("val") ) then  // do something with $a end ^ Ideally this would tell the rule "derivation rule" to attempt to derive A(), but under the assumption that param1 should be initialized with "new Param1("val")" as opposed to strictly matching for it in WM.  However, the more I look at this, more it seems like backward chaining is necessary... -- View this message in context: http://drools.46999.n3.nabble.com/Partial-Unification-Derivation-of-Facts... 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