Just noticed that the patch references the function which is not yet defined when you eval the buffer for the first time (from 'require). So either relevant defun should be before defcustom, or you need to change :set value to not use not-yet-defined functions.
Just noticed that the patch references the function which is not yet defined when you eval the buffer for the first time (from 'require). So either relevant defun should be before defcustom, or you need to change :set value to not use not-yet-defined functions.