anchor.diff:  (defun get-macro-character (char &optional (readtable *readtable*))
     (let ((entry (gethash char (macro-characters readtable))))
       (values
  -     (if (functionp entry) entry nil)
  +     entry
        (eq (gethash char (syntax-types readtable)) :non-terminating-macro))))
   
   (defun sharpsign (stream char)
  
positive.code:     (error 'sub-char-must-not-be-a-decimal-digit
  	   :disp-char disp-char
  	   :sub-char sub-char))
    (setf sub-char (char-upcase sub-char))
    (let ((subtable (gethash disp-char (dispatch-macro-characters readtable))))
      (when (null subtable)
        (error 'char-must-be-a-dispatching-character
  
negative.code:     (disp-char sub-char &optional (readtable *readtable*))
    ;; The HyperSpec does not say whether we should convert
    ;; to upper case here, but we think we should.
    (let ((subtable (gethash disp-char (dispatch-macro-characters readtable))))
      (when (null subtable)
        (error 'char-must-be-a-dispatching-character
  	     :disp-char disp-char))
  