anchor.diff:    (setf (get-fact-id fact) (next-fact-id self))
     (increment-time self)
     (update-time fact self)
  -  (add-fact-to-engine self fact)
  +  (record-fact self fact)
     (insert-token self (make-add-token :initial-fact fact))
     (values fact))
     
  
positive.code:    (clock :initform 0
            :accessor get-clock)
     (fact-list :initform nil
                :accessor get-fact-list))
    (:documentation
     "Represents the inference engine itself."))
  
  
negative.code: ;;; File: rete.lisp
  ;;; Description: Class representing the inference engine itself.
  
  ;;; $Id: rete.lisp,v 1.11 2000/11/17 16:45:51 youngde Exp $
  
  (in-package :lisa)
  
  