(deftemplate pants-color (slot of) (slot is))
(deftemplate position (slot of) (slot is))
(defrule generate-possibilities
=>
(foreach ?name (create$ Fred Joe Bob Tom)
(foreach ?color (create$ red blue plaid orange)
(assert (pants-color (of ?name)
(is ?color))))
;;共有16种循环结果比如Fred red;Fred blue。。。。。
(foreach ?position (create$ 1 2 3 4)
(assert (position (of ?name)
(is ?position))))))
(defrule find-solution
;; There is a golfer named Fred, whose position is ?p1
;; and pants color is ?c1
(position (of Fred) (is ?p1))
(pants-color (of Fred) (is ?c1))
;; The golfer to Fred's immediate right
;; is wearing blue pants.
(position (of ?n&~Fred)
(is ?p&
eq ?p (+ ?p1 1))))
(pants-color (of ?n&~Fred)
(is blue&~?c1))
;; We don't know anything about Joe, really
(position (of Joe) (is ?p2&~?p1))
(pants-color (of Joe) (is ?c2&~?c1))
;; Bob is wearing the plaid pants
(position (of Bob)
(is ?p3&~?p1&~?p&~?p2))
(pants-color (of Bob&~?n)
(is plaid&?c3&~?c1&~?c2))
;; Tom isn't in position 1 or 4
;; and isn't wearing orange
(position (of Tom&~?n)
(is ?p4&~1&~4&~?p1&~?p2&~?p3))
(pants-color (of Tom)
(is ?c4&~orange&~blue&~?c1&~?c2&~?c3))
=>
(printout t Fred " " ?p1 " " ?c1 crlf)
(printout t Joe " " ?p2 " " ?c2 crlf)
(printout t Bob " " ?p3 " " ?c3 crlf)
(printout t Tom " " ?p4 " " ?c4 crlf crlf))
this is the program ,and when i run it ,the result is
Jess, the Rule Engine for the Java Platform
Copyright (C) 2004 Sandia Corporation
Jess Version 7.0a6 3/23/2005
This copy of Jess will expire in 83 day(s).
i want to know why i cant see the result ??
