anchor.diff:  			   (? (%setq? last.)
   				  (? (eq s (second last.))
   				     (expex-guest-filter-setter ex last.)
  -				     (expex-make-setq-copy ex last s))
  +				     (expex-copy-%setq ex last s))
   				  (expex-make-%setq ex s last.)))
   		x)))
   
  
positive.code:         (list x))
  	  (expex-make-%setq ex '~%ret x)))
  
  (defun expex-make-setq-copy (ex x s)
    (? (eq s (second x.))
       x
       `(,x.
  
negative.code: 
  (defun expression-expand (ex x)
    (when x
      (with-temporary *expexsym-counter* 0
  	  (with-temporary *current-expex* ex
  	    (with-temporary *expex-funinfo* (transpiler-global-funinfo *current-transpiler*)
            (expex-body ex x))))))
  