; Changes:
  * removed : 0
  * added : 0
  * swaps : 0
  * negated predicates : 1
; * swapped branches: 0
  * calls to i d fun : 1
(letrec ((count (lambda (n)
                  (if (<change> (= n 0) (not (= n 0)))
                     "done"
                     (count (- n 1))))))
   (<change>
      (count 10)
      ((lambda (x) x) (count 10))))
 Changes:
 * swapped branches: 0
  * removed : 0
  * added : 0
  * swaps : 0
  * negated predicates : 1
  * calls to i d fun : 1
(letrec ((count (lambda (n)
                  (if (<change> (= n 0) (not (= n 0)))
                     "done"
                     (count (- n 1))))))
   (<change>
      (count 10)
      ((lambda (x) x) (count 10))))