Re: [calsify] SKIP was Re: AD review of draft-ietf-calext-rscale-03

[Cyrus Daboo <[e-mail]>]

Hi Marten,

--On February 3, 2015 at 9:58:55 PM +0100 Marten Gajda <[e-mail]> 
wrote:

>> But if we use 20140229 as the DTSTART - and that is a leap day on a
>> Sunday - then I think Marten is write that apply the SKIP after the
>> BYMONTH and before the BYDAY would result in only Sundays in leap
>> years being returned.
>>
>> I think having those two rules return different results would be
>> counterintuitive so I would prefer we left the order of BYxxx element
>> and SKIP processing as it is now.
>>
> you meant 20040229, right?

Yes!

> The point is, that evaluating SKIP=OMIT after BYMONTH=2 would remove Feb
> 29th in non-leap years and there would be nothing left for BYDAY to
> expand.
>
> I'd also prefer having SKIP=OMIT behave like a rule without RSCALE.
>

I think Ken's idea is that you apply the SKIP after BYMONTH only if the 
invalid data corresponds to an invalid leap month as opposed to a leap day. 
In which case the SKIP would not have applied after BYMONTH in your 
example. But I think a behavior like that is going to be really tricky for 
implementors to get right and hard to describe really well without having 
to delve into the gory details of RRULE processing.

-- 
Cyrus Daboo