Perhaps the discussion in http://www.jessrules.com/jesswiki/view?PropertySet is useful for you. -W
On Mon, Feb 23, 2009 at 6:11 PM, Wolfgang Laun <[email protected]>wrote: > On Mon, Feb 23, 2009 at 5:22 PM, Joao Antunes Mourao < > [email protected]> wrote: > >> Hello, >> >> /(defrule get-black-cars >> (car (id ?id1) (color "black")) >> (car (id ?id2 &:(~= ?id1 ?id2)) (color "black")) >> (and (not (black-cars (car-id ?id1 ?id2)) (not (black-cars (car-id ?id2 >> ?id1))) >> => >> (assert (black-cars (car-id ?id1 ?id2)))/ >> > > The second CE is better written as > (car (id ?id2 & ~?id1)) (color "black")) > >> >> My question is: There is a matching way of avoid this comparison? The only >> thing i want to know is which are the black cars, not the order. >> >> You are talking of sets (in the mathematical sense). For the general case > you might consider using a java.util.Set as a (non-multi-)slot value. > > -W > > >
