anchor.diff:     (current-timestamp :initform 0 :accessor scsu-state-current-timestamp :type fixnum)
      (fix-dynamic-window :initarg :fixed-window :initform *scsu-state-default-fix-dynamic-window*
   		       :reader scsu-state-fix-dynamic-window :type boolean)
  -   (trace :initarg :trace :initform *scsu-state-default-trace*
  -	  :reader scsu-state-trace :type boolean)))
  +   ))
   
   (defmethod lookup-dynamic-window (state window)
     (declare (type window-index window))
  
positive.code: 
  ;;; State
  (defvar *scsu-state-default-fix-dynamic-window* nil)
  (defvar *scsu-state-default-trace* nil)
  (defvar *scsu-state-trace* nil)
  
  (defclass scsu-state ()
  
negative.code:     (:unicode-mode (decode-unit*/unicode-mode state read-func))))
  
  (defun decode-unit (state read-func)	; TODO: use defmethod :around
    (prog2 (scsu-trace-output "~&")
        (decode-unit* state read-func)
      (scsu-trace-output "~%")))
  
  (defun decode-to-string (bytes
  			 &key (start1 0) (end1 (length bytes))
  