anchor.diff:                                      (destructuring-bind (vname vval) v
                                         `((eq sym ',vname) ,vval)))
                                     vals)
  -                        (t (error "Unexpected enum value ~A expexted one of ~A"
  -                                  sym
  -                                  ',(mapcar #'car vals))))))))
  +			(t (error "Unexpected enum value ~A expected one of ~A"
  +				  sym
  +				  ',(mapcar #'car vals))))))))
  
positive.code: NAME ::= type name
  OPTIONS ::= list of options
  VALS ::= list of forms (symbol integer)*."
    (declare (ignore options))
    `(progn
       (defxdecoder ,name (blk)
         (let ((val (decode-int32 blk)))
  
negative.code:                        (destructuring-bind (vname vval) v
                           `((= val ,vval) ',vname)))
                       vals)
             ,(if (cadr (assoc :exclusive options))
  		`(t (error "Unexpected enum value ~A expected one of ~A"
  			 val
  			 ',(mapcar #'cadr vals)))
  		`(t val)))))
       (defxencoder ,name (blk sym)
         (encode-uint32 blk
                        (cond
  