anchor.diff:      (let ((prev-end 0)
             (x start-x))
         (loop :for (start end attr) :in attributes
  -	 :do (setf end (min (length str) end))
  -	 :do (progn
  -	       (screen-print-string-attr screen x y (subseq str prev-end start) nil)
  -	       (incf x (string-width str prev-end start)))
  -	 :do (progn
  -	       (screen-print-string-attr screen x y (subseq str start end) attr)
  -	       (incf x (string-width str start end)))
  -	 :do (setf prev-end end))
  +            :do (setf end (min (length str) end))
  +            :do (progn
  +                  (screen-print-string-attr screen x y (subseq str prev-end start) nil)
  +                  (incf x (string-width str prev-end start)))
  +            :do (progn
  +                  (screen-print-string-attr screen x y (subseq str start end) attr)
  +                  (incf x (string-width str start end)))
  +            :do (setf prev-end end))
         (screen-print-string-attr screen x y
                                   (if (= prev-end 0)
                                       str
  
positive.code:     (when mark-overlay
        (delete-overlay mark-overlay))))
  
  (defun screen-display-line-wrapping (screen view-charpos
                                              visual-cursor-x visual-cursor-y
                                              point-x point-y str/attributes)
    (when (and (< 0 view-charpos) (= point-y 0))
  
negative.code: 
  (defun disp-print-line (screen y str/attributes do-clrtoeol
                                 &key (start-x 0) (string-start 0) string-end)
    (destructuring-bind (str . attributes)
        str/attributes
      (when (null string-end)
  