Function: undo-start

undo-start is a byte-compiled function defined in simple.el.gz.

Signature

(undo-start &optional BEG END)

Documentation

Set pending-undo-list to the front of the undo list.

The next call to undo-more will undo the most recently made change. If BEG and END are specified, then undo only elements that apply to text between BEG and END are used; other undo elements are ignored. If BEG and END are nil, all undo elements are used.

Source Code

;; Defined in /usr/src/emacs/lisp/simple.el.gz
(defun undo-start (&optional beg end)
  "Set `pending-undo-list' to the front of the undo list.
The next call to `undo-more' will undo the most recently made change.
If BEG and END are specified, then undo only elements
that apply to text between BEG and END are used; other undo elements
are ignored.  If BEG and END are nil, all undo elements are used."
  (if (eq buffer-undo-list t)
      (user-error "No undo information in this buffer"))
  (setq pending-undo-list
	(if (and beg end (not (= beg end)))
	    (undo-make-selective-list (min beg end) (max beg end))
	  buffer-undo-list)))