File psl-1983/3-1/tests/20/p from the latest check-in

(de errorprintf(a1 a2 a3 a4 a5)
 (prin2 a1)
 (prin2 " ")
 (prin2 a2)
 (prin2 " ")
 (prin2 a3)
 (prin2 " ")
 (prin2 a4)
 (prin2 " ")
 (prin2t a5))

(setq knt 0)
(df tr (z)
   (setq old (car z))
   (setq new (cadr z))
   (setq args (cddr z))      
   (copyd new old)
   (putd old 'expr (list 'lambda args 
            	    '(setq knt (add1 knt))
                     (list 'print (list 'list ">>>>" (list 'quote old)  'knt))
                      (list 'setq 'ans  (cons new args))
                      (list 'print (list 'list "   <" (list 'quote old)  'knt))
             	    '(setq knt (sub1 knt))
                      'ans)))

(df m (z)
   (setq old (car z))
   (setq new (cadr z))
   (setq args (cddr z))      
   (copyd new old)
   (print (list old (inf old)))
   (putd old 'expr (list 'lambda args 
                     (list 'print (list 'inf old))
                      (cons new args))))