Hi,

please find attached a patch to allow more flexible handling of missing ids in org-id-find; some people (like me) tend to lose ids now and then and may benefit from more choices.

The current behaviour of calling org-id-update-id-locations is pretty perfect for situations where the id has been moved to another file (which will be the case in most situations, I guess). However, sometimes an id has simply been deleted and then searching for it in all files can not be helpful. Especially lisp-code calling org-id-find might want to handle things on its own.

To this goal, a new custom org-id-action-on-missing-id has been added; reproducing its description from the patch:

> (defcustom org-id-action-on-missing-id 'update
>   "Special action to be taken, if `org-id-find' cannot find an id.
> 
> With 'update (default), org-id-find will silently call
> `org-id-update-id-locations' and try again; this will help,
> e.g. if you have moved the id to another file.
> 
> With 'exception, the exception 'not-found will be thrown, which
> can be useful, if `org-id-find' is called from within lisp and
> the caller wants to handle the situation.
> 
> With 'error, a descriptive error will be raised, causing the
> current command to terminate."
>   :group 'org-id
>   :type '(choice
> 	  (const :tag "Run `org-id-update-id-locations' if an id cannot be found" update)
> 	  (const :tag "Throw exception `not-found'" exception)
> 	  (const :tag "Raise an error" error)
>           ))

the handling in org-id-find is straightforward.

The default corresponds to the current behaviour.
 
I would like to ask for opinions/discussion on this patch and maybe see it applied if found fit.

Best regards
Marc Ihm