Re: [calsify] Feedback on draft-ietf-calext-icalendar-series

Am 22.11.19 um 04:36 schrieb Neil Jenkins:
> On Thu, 21 Nov 2019, at 00:00, Marten Gajda wrote:
>>
>> I like the idea of a separate SRULE. It allows you to declare series 
>> of recurring events. That way you can specify more complex recurrence 
>> patterns which you can't express with a single RRULE.
>>
>
> I'm not sure exactly what you mean by this; do you just mean you can 
> have multiple recurrence rules? Because that's no reason why a 
> VTEMPLATEEVENT can't have multiple RRULE properties. I don't think 
> SRULE was any different to RRULE other than being a different name to 
> differentiate it when sharing a component namespace, which is not 
> required if it's a different component.

I'm not talking about merely merging the instances of multiple RRULES. 
When we have an SRULE, the RRULE property would not be interpreted by 
the series and go as-is into the resulting VEVENT.

Consider this series:

DTSTART:20190611T12:00:00Z
SRULE:FREQ=YEARLY;BYMONTH=6;BYDAY=2MO
RRULE:FREQ=DAILY;COUNT=4

It would result in the following first few VEVENTS

DTSTART:20190611T12:00:00Z
RRULE:FREQ=DAILY;COUNT=4

DTSTART:20200608T12:00:00Z
RRULE:FREQ=DAILY;COUNT=4

DTSTART:20210614T12:00:00Z
RRULE:FREQ=DAILY;COUNT=4

This results in composition of recurrence pattern rather than of the 
union of both recurrence patterns, i.e. you first apply the SRULE and 
then apply the RRULE on every result of the SRULE.

Also I want to advice against calling the object VTEMPLATEEVENT. 
VEVENTSERIES would be a better name because this is not what I would 
expect from a true template. From a template I'd expect to support 
placeholders I can provide when instantiating the template into a VEVENT.

Marten

>
> Neil.
>
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