(defclass ahoclass :slots (a b c))

(defmethod ahoclass
 (:set (n) (setq a n))
 (:inc (n) (incf a) (print a) (if (> n 0) (send self :inc (1- n)))))

(setq aho1 (instantiate ahoclass) aho2 (instantiate ahoclass))

(setq a (open "fib.l"))

