I'm trying to get org-mode to automatically mark DONE when all sub checkboxes are checked. On http://orgmode.org/worg/org-faq.html, I found a function that purports to do this.

I pasted the function into my .emacs file, but now I'm getting an error message when I launch: "Symbol's value as variable is void: org-checkbox-statistics-hook."

;; see http://thread.gmane.org/gmane.emacs.orgmode/42715

(add-to-list 'org-checkbox-statistics-hook (function ndk/checkbox-list-complete))

(defun ndk/checkbox-list-complete ()

(save-excursion

(org-back-to-heading t)

(let ((beg (point)) end)

(end-of-line)

(setq end (point))

(goto-char beg)

(if (re-search-forward "\\[\\([0-9]*%\\)\\]\\|\\[\\([0-9]*\\)/\\([0-9]*\\)\\]" end t)

(if (match-end 1)

(if (equal (match-string 1) "100%")

;; all done - do the state change

(org-todo 'done)

(org-todo 'todo))

(if (and (> (match-end 2) (match-beginning 2))

(equal (match-string 2) (match-string 3)))

(org-todo 'done)

(org-todo 'todo))))))))