Re: [rules-users] insertLogical and modifyRetract (drools-solver)

thanks, you are right, that is kind of a solution. but not really what i am looking for. i am using drools-solver, and the "CreatedFact" is an IntConstraintOccurrence, which i do not want to change. maybe i should make the example more specific for my problem. i have a rule, used for the solver: rule "fact1 should be smaller then 1" when $f : UserFact(fact1 >= 1); then // use the value of fact1 to determine the error insertLogical(new IntConstraintOccurence("fact1 should be smaller then 1", $f.getFact1(), $f )); end i have a Move that decrements fact1, so that after the move the error should be 1 smaller. but the move is almost never triggered, because the old constraintOccurence is not retracted from memory and the new one added anyway, hence the error is nearly double after the move, as now two constraintOccurences represent the same error. what i could think of is something like this: one rule for the first test: rule "fact1 should be smaller then 1" when $f : UserFact(fact1 >= 1) not IntConstraintOccurence( ruleId == "fact1 should be smaller then 1", constraintType == ConstraintType.NEGATIVE_SOFT, causes contains $f) then // use the value of fact1 to determine the error insertLogical(new IntConstraintOccurence("fact1 should be smaller then 1", $f.getFact1(), $f )); end and a second rule, when the first rule has already fired before: rule "fact1 should be smaller then 1, old constraint exists" when $f : UserFact(fact1 >= 1); // see if there is already a fact in the $oldConstraint : IntConstraintOccurence( ruleId == "fact1 should be smaller then 1", constraintType == ConstraintType.NEGATIVE_SOFT, causes contains $f) then retract($oldConstraint); // manually retract the obsolete fact // use the value of fact1 to determine the error insertLogical(new IntConstraintOccurence("fact1 should be smaller then 1",ConstraintType.NEGATIVE_SOFT, $f.getFact1(), $f )); end this solution seems very verbose for such a common task. and again, i do not understand, why an obsolete fact is not retracted automatically? best, tim On Tue, Oct 7, 2008 at 5:57 PM, Gras, Patrick <Patrick.Gras(a)generali.ch&gt;wrote: