The definition of orig-fn.

[Hongyi Zhao]

I'm trying to understand the code snippet here [1] as follows:

;;;
(defun ora--company-good-prefix-p (orig-fn prefix)
(unless (and (stringp prefix) (string-match-p "\\`[0-9]+\\'" prefix))
(funcall orig-fn prefix)))
(ora-advice-add 'company--good-prefix-p :around #'ora--company-good-prefix-p)
;;;

The symbol `orig-fn' used above puzzles me the most. It can't be found
by `C-h o orig-fn RET', and its definition cannot be found elsewhere
in the above repository.

[1] 
https://github.com/abo-abo/oremacs/blob/3809390019a7083c28e8502a82da94ca3a8ebba0/modes/ora-company.el#L41

Regards, HZ