How to fold the highest headline which I am currently in?

Question

I often do the following sequence in my org-mode file:

1. Go to the root headline from current position
2. Fold the whole subtree

Is there a way to this sequence with a shortcut?

Answer 1

The following code (lightly tested) takes advantage of the fact that org-mode is derived from outline-mode, which allows you to use the latter's functions. It simply jumps up headlines until it can't go any further, and then hides the subtree.

(defun foldup ()
  "Hide the entire subtree from root headline at point."
  (interactive)
  (while (ignore-errors (outline-up-heading 1)))
  (hide-subtree))

Bind it to your key of choice if you use it frequently.