[emacs-wiki-discuss] Re: Making one task dependent on another.

[Sacha Chua]

Alex Polite <address@hidden> writes:

> Is there a way (in muse or emacs-wiki) to make one task dependent on
> another? I've have a lot of tasks that shouldn't be displayed until
> some other task (that they depend upon) is completed.

I usually make them undated tasks on the project page. I have some
code to automatically schedule the next unscheduled task from the
project when I complete a task. That fakes dependencies a bit
and also neatly supports GTD's next actions.

;;_+ Schedule next undated task from same project

(defun sacha/planner-seek-next-unfinished-and-undated-task ()
  "Move point to the next unfinished task on this page.
Return nil if not found, the task if otherwise."
  (interactive)
  (let (task-info)
    (while (and (not task-info)
                (re-search-forward "^#[A-C][0-9]*\\s-+[^CX]\\s-+" nil t))
      (setq task-info (planner-current-task-info))
      (when (planner-task-date task-info) (setq task-info nil)))
    task-info))

(defun sacha/planner-queue-next-task (&optional task-info)
  "Schedule the next task for TASK-INFO or the current task for today."
  (interactive)
  (save-window-excursion
    (save-excursion
      (setq task-info (or task-info (planner-current-task-info)))
      (when (and task-info (planner-task-plan task-info))
        (planner-find-file (planner-task-plan task-info))
        (goto-char (point-min))
        (if (sacha/planner-seek-next-unfinished-and-undated-task)
            (planner-copy-or-move-task (planner-today))
          (message "No more unscheduled tasks for %s."
                   (planner-task-plan task-info)))))))

(defun sacha/planner-schedule-next-task (old-status new-status)
  "Schedule next task if there are no other unfinished tasks for this project."
  (when (and (string= new-status "X")
             (not (string= old-status "X")))
    (let ((task-info (planner-current-task-info))
          (not-seen t))
      (when (and task-info
                 (planner-task-plan task-info)
                 (planner-task-date task-info))
        (save-window-excursion
          (save-excursion
            (when (string= (planner-task-plan task-info)
                           (planner-task-page task-info))
              (planner-jump-to-linked-task))
            (goto-char (point-min))
            (while (and not-seen
                        (re-search-forward "^#[A-C][0-9]*\\s-+[^CX]\\s-+" nil 
t))
              (let ((current (planner-current-task-info)))
                (when (string= (planner-task-plan task-info)
                               (planner-task-plan current))
                  (setq not-seen nil))))))
        (when not-seen
          (sacha/planner-queue-next-task task-info)))))
  t)
(add-hook 'planner-mark-task-hook 'sacha/planner-schedule-next-task)


-- 
Sacha Chua <address@hidden> - open source geekette
http://sacha.free.net.ph/ - PGP Key ID: 0xE7FDF77C
interests: emacs, gnu/linux, personal information management, juggling
sachac on irc.freenode.net#emacs . YM: sachachua83