Re: [VCARDDAV] Questions, Concerns, and Errata concerning vcardrev-13

Cyrus Daboo <> Tue, 12 October 2010 14:42 UTC

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Date: Tue, 12 Oct 2010 10:43:07 -0400
From: Cyrus Daboo <>
To: Rohit Khare <>,
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Subject: Re: [VCARDDAV] Questions, Concerns, and Errata concerning vcardrev-13
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Hi Rohit,
Since CALSCALE was my suggestion I feel I have to reply specifically on 
this point. This also relates to Tantek's comments on CALSCALE on his wiki 
page review.

--On October 11, 2010 11:42:25 PM -0700 Rohit Khare <> wrote:

> * 5.8 c’mon, really? You’re going to justify *@&# like DEATH on
> genealogical bases, and I can’t even create a stock vCard for Jesus H.
> Christ? Where’s B.C.E.? And next I suppose I’ll be told I can’t I
> use  for
> cataloging notable guillotinings. Not to mention offending followers of
> ,
>  , or
> And don’t forget TIME while
> you’re at it:
> Punting by saying, “well, there’s only one true defined meaning, but
> you can plug in anything else you want as x- or ask IANA” is not a
> decision that supports diversity — it’s a decision to favor exactly
> one point of view.
> This kind of Eurocentric dead-white-male crap is inexcusable in my
> opinion. Either there’s a legitimate degree of freedom required here,
> with documented, interoperable use cases, or it’s just useless — no,
> scratch that, *offensive* - preening.

> Now, of course, it happens to be that every single use of *address book*
> software that I’ve been exposed to uses Gregorian dates. Every other
> CALSCALE use that might make sense for people, organizations, or things
> in general is appealing to the existence of software yet unwritten —
> and if you can use it to create a concordance of Star Trek characters,
> I’ll bet it won’t be called an “address book” or a “contact
> card” either.

The use of CALSCALE here follows what is done in iCalendar. Whilst a single 
"static" date can often be trivially converted between different calendar 
systems, anything that involves "recurrence" (repeating events at some 
frequency) cannot be treated the same. In particular, for vCard we use 
"anniversaries" a lot. Yet one year in one calendar system is not 
necessarily the same number of days as one year in another. So an 
anniversary that occurs in a specific calendar system must be tagged as 
such, else repeating instances cannot be accurately determined.

Also, whilst I can't speak for other OS's, I can tell you that on OS X you 
can enter and edit dates in different calendar systems. That involves 
changing the overall calendar "locale" in the system preferences. Once 
done, all the "date pickers" in the UI adjust accordingly including the 
ones for specifying anniversaries etc in However, the app 
generates vCard dates in Gregorian, so in theory repeating instances of 
anniversaries in other calendar scales will be wrong.

Now, is this a real problem? I really can't say whether users are clamoring 
for a fix. However, I believe we should take the time to fix it. The fact 
that we have not formally defined CALSCALEs beyond GREGORIAN is a side 
issue. Already, there has started to be more interest from various parties 
to work on extending iCalendar with non-GREGORIAN CALSCALE, so that work 
will filter down to vCard too. Perhaps we should tie the vCard value to the 
iCalendar registry for CALSCALE values so we stay in sync.

Cyrus Daboo