"Samuel Banya" <sbanya@fastmail.com> writes:

> I often change states of my todo list items to 'DONE', 'CANCELLED', etc.
>
> However, one thing I would want to know is this:
> - Is it possible to automatically delete the '#' priority value of a task after a task has been marked as 'DONE', 'CANCELLED', etc?
>
> Is this done via a hook function?

To do it globally:

--8<---------------cut here---------------start------------->8---
(defun my/org-trigger-hook (change-plist)
  (let* ((type (plist-get change-plist :type))
         (pos (plist-get change-plist :position))
         (from (substring-no-properties (or (plist-get change-plist :from) "")))
         (to (substring-no-properties (or (plist-get change-plist :to) "")))
         )
    (when (and
           (eq type 'todo-state-change)
           (member to org-done-keywords)
           (member from org-not-done-keywords)
           )
      (org-priority (string-to-char " "))
      )
    )
  )

(add-hook #'org-trigger-hook
          #'my/org-trigger-hook)
--8<---------------cut here---------------end--------------->8---


But if, like me, you want to define this behavior per task, this is one
of the purposes of org-edna. I suggest you try it.

I your particular example, you would simply set the TRIGGER property of
the task for which you want to delete the priority to this content

--8<---------------cut here---------------start------------->8---
* NEXT [#B] some task
:PROPERTIES:
:TRIGGER: self() set-priority!(" ")
:END:
--8<---------------cut here---------------end--------------->8---

Closing it would result in

--8<---------------cut here---------------start------------->8---
* DONE some task
  CLOSED: [2021-12-11 Sat 13:38]
:PROPERTIES:
:TRIGGER: self() set-priority!(" ")
:END:
--8<---------------cut here---------------end--------------->8---

Of course, it also work for repeated task or any complicated scenario
I have tried so far.

I hope that helps,
-- 
Konubinix
GPG Key    : 7439106A
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