Function: rcirc-update-undo-list

rcirc-update-undo-list is a byte-compiled function defined in rcirc.el.gz.

Signature

(rcirc-update-undo-list SHIFT)

Documentation

Translate buffer positions in buffer-undo-list by SHIFT.

Source Code

;; Defined in /usr/src/emacs/lisp/net/rcirc.el.gz
;; Copied from lisp/erc/erc.el (erc-update-undo-list)
(defun rcirc-update-undo-list (shift)
  "Translate buffer positions in buffer-undo-list by SHIFT."
  (unless (or (zerop shift) (atom buffer-undo-list))
    (let ((list buffer-undo-list) elt)
      (while list
        (setq elt (car list))
        (cond ((integerp elt)           ; POSITION
               (incf (car list) shift))
              ((or (atom elt)           ; nil, EXTENT
                   ;; (eq t (car elt))  ; (t . TIME)
                   (markerp (car elt))) ; (MARKER . DISTANCE)
               nil)
              ((integerp (car elt))     ; (BEGIN . END)
               (incf (car elt) shift)
               (incf (cdr elt) shift))
              ((stringp (car elt))      ; (TEXT . POSITION)
               (incf (cdr elt) (* (if (natnump (cdr elt)) 1 -1) shift)))
              ((null (car elt))         ; (nil PROPERTY VALUE BEG . END)
               (let ((cons (nthcdr 3 elt)))
                 (incf (car cons) shift)
                 (incf (cdr cons) shift))))
        (setq list (cdr list))))))