Subject: [Sedate] Calendar systems

From: Michael Douglass <[email-masked]>
Date: Tue, 7 Dec 2021 11:51:13 -0500

Reading through the draft I can't tell what the intent of this is:

> 1996-12-19T16:39:57-08:00[America/Los_Angeles][u-ca=hebrew]
> Figure 5 
> <https://www.ietf.org/archive/id/draft-ietf-sedate-datetime-extended-02.html#figure-5>: 
> Projecting to the Hebrew calendar 
> <https://www.ietf.org/archive/id/draft-ietf-sedate-datetime-extended-02.html#name-projecting-to-the-hebrew-ca> 
>
>
> Figure 5 
> <https://www.ietf.org/archive/id/draft-ietf-sedate-datetime-extended-02.html#date-time-hebrew> 
> represents the exact same instant, but it informs calendar-aware 
> implementations that they should project it to the Hebrew calendar.
>
Is it a hint that it might be appropriate to display the Hebrew date - 
for example a website listing Jewish religious festivals or it it 
something else.

I assume we're not trying to say the date is actually a Hebrew calendar 
date? Or are we?

I'm not even sure it helps with time/date calculations - if I as a 
non-Hebrew calendar person wants to set an alarm 1 month ahead I 
probably mean a Gregorian 1 month - but perhaps I'm wanting to know the 
Hebrew 1 month ahead - but I might want that even if the date is Gregorian.

---

From: Edward Welbourne <[email-masked]>
Date: Tue, 7 Dec 2021 17:27:57 +0000

Figure 5: Projecting to the Hebrew calendar

  Figure 5 represents the exact same instant, but it informs
  calendar-aware implementations that they should project it to the
  Hebrew calendar.

> I assume we're not trying to say the date is actually a Hebrew
> calendar date? Or are we?

I'm a total n00b to this list, but (not entirely unfamiliar with
calendars and date-times) I would indeed understand the wording in the
given example as saying the given date is a perfectly usual ISO 8601
date in the Gregorian calendar, but encouraging the receiving software
to *display* it using the Hebrew calendar's description of the exact
same moment.  Software lacking support for that calendar would be
entirely within its rights to ignore the annotation, IIUC.

> probably mean a Gregorian 1 month - but perhaps I'm wanting to know
> the Hebrew 1 month ahead - but I might want that even if the date is
> Gregorian.

hmm ... well, I guess the receiving software would display an event as
starting at the given time; and it's up to the UI to, hopefully, let the
user switch between calendars when selecting when to set an alarm ahead
of it.  OTOH, setting alarms a month ahead probably isn't high on the UI
designer's list of priorities.

And - speaking of being a n00b - Hi, I'm one of the Qt project's
developers, I take particular care of the l10n, date, time, time-zone
and calendar parts of the open source / free Qt framework, and I'm
paying attention because I'll probably want to add support for whatever
format you all end up deciding on,

	Eddy.

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From: Justin Grant <[email-masked]>
Date: Thu, 9 Dec 2021 11:19:03 -0800

> I would indeed understand the wording in the

This matches our expectations on the JavaScript Temporal side. It's a hint
for the receiving application to know about the calendar preference of the
sending user, e.g. for display.

On Tue, Dec 7, 2021 at 9:28 AM Edward Welbourne <[email-masked]>
wrote:

> --
> Sedate mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/sedate
>

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From: Michael Douglass <[email-masked]>
Date: Thu, 9 Dec 2021 14:41:04 -0500

On 12/9/21 14:19, Justin Grant wrote:
> This matches our expectations on the JavaScript Temporal side. It's a 
> hint for the receiving application to know about the calendar 
> preference of the sending user, e.g. for display.
My point was not that that's what we understand but that it needs to be 
stated explicitly - because it's guaranteed that some people will 
understand differently.
>
> On Tue, Dec 7, 2021 at 9:28 AM Edward Welbourne 
> <[email-masked]> wrote:
>

---

From: Justin Grant <[email-masked]>
Date: Thu, 9 Dec 2021 11:56:38 -0800

> stated explicitly - because it's guaranteed that some people will

Agreed.