Re: iCal export of repeated tasks

[Adam Spiers <orgmode@adamspiers.org>]

On Fri, Jun 13, 2008 at 10:18:52AM +0200, Carsten Dominik wrote:
> On Jun 12, 2008, at 1:47 PM, Adam Spiers wrote:
> >Well, I agree that there may not be a good definition, in which case a
> >per-event property disabling export of the RRULE would be a perfect
> >solution.
> 
> Hi Adam,
> 
> I do not feel comfortable with this specialized filtering, so I am not  
> implementing it.  It seems incorrect that the export of the exact same  
> Org file would lead to different iCal files, depending on the day when  
> you do the export.

Sorry - either I have accidentally misled you, or my understanding is
missing some nuance of your argument, because it was certainly not my
intention to propose a mechanism which would produce different results
depending on when the export is done.  I simply wanted to suggest that
there could be a property which would have the same effect upon iCal
export as would manually deleting the directive to repeat ('.+2w' or
similar) from the end of the task's timestamp.  This would maintain
the existing behaviour for repeated tasks within Org, but display it
as a non-repeating task in my external calendaring clients
(korganizer, ScheduleWorld, Google Calendar, my Nokia phone etc.)

The motivation is that while I very much like org's functionality for
automatically updating the timestamp on a repeated task once it has
been marked as done, I do not want tasks such as "water plants"
cluttering up my calendar forever into the future.  I only care about
the next plant watering, not all others thereafter, and with screen
real estate always short in supply (especially on mobile devices!),
any possible savings are of value.

Actually, now I think about it more, the above decluttering argument
applies equally to the Org agenda itself.  So if it would be a more
consistent request from the point of view of maintaining an intuitive
UI or from ease of implementation, I would be perfectly happy if the
proposed property disabled display of all but the first instance of
the repeated task *everywhere*, i.e. not only in iCal exports, but
also in agenda displays.

> It seems to be fine for the program displaying the info to do such
> filtering - this is what Org does in the agenda.

Unfortunately, since the proposed filtering is per-event, with
uni-directional export to other clients, the only place it can be done
is at the source, i.e. within Org.  Otherwise some layering of extra
filtering meta-data per-event would be required for each external
calendaring client, which would be extremely cumbersome.