anchor.diff:  	(expex-move-arg-std ex x)))
   
   (defun expex-filter-and-move-args (ex x)
  -  (assoc-splice (mapcar (fn expex-move-arg ex _)
  -   		                (expex-guest-filter-arguments ex x))))
  +  (assoc-splice (mapcar (fn expex-move-arg ex _) (expex-guest-filter-arguments ex x))))
   
   (defun expex-move-slot-value (ex x)
     (with ((moved new-expr) (expex-filter-and-move-args ex (list .x.)))
  
positive.code: ;;
  ;; Rejects atoms and expressions with meta-forms.
  (defun expex-able? (ex x)
    (not (or (atom x)
  		   (function-ref-expr? x)
             (in? x. '%%vm-go '%%vm-go-nil
  				   '%transpiler-native '%transpiler-string
  				   '%quote))))
  
  ;; Check if an expression has a return value.
  (defun expex-returnable? (ex x)
  
negative.code: (defun expex-force-%setq (ex x)
    (or (when (metacode-expression-only x)
          (list x))
  	  (expex-guest-filter-setter ex `(%setq ~%ret ,(peel-identity x)))))
  
  (defun expex-make-setq-copy (ex x s)
    (if (eq s (second x.))
        x
        `(,x.
  	    ,@(expex-guest-filter-setter ex `(%setq ,s ,(second x.))))))
  
  (defun expex-make-return-value (ex s x)
    (let last (last x)
     	(if (expex-returnable? ex last.)
  