[tz] Timezone selectors (was RES: Timezone for Brazil)

Doug Ewell doug at ewellic.org
Tue Oct 10 23:48:07 UTC 2023

Guy Harris wrote:

> Users ideally shouldn't be exposed to the tzdb maintainers' choices of
> LOCATIONs at all.  "Los Angeles" isn't much better than
> "America/Los_Angeles", especially for people not in the LA area.

> And, depending on the locale, there might be ways of choosing between
> different timezones that cover the same time zone, e.g.
>	(UTC-7:00) Mountain Time (most locations)
>	(UTC-7:00) Mountain Time (Arizona)
> (with whatever tweaks would be most straightforward to include the
> Navajo Nation and the Hopi Nation) that might be more obvious than
>	(UTC-7:00) Mountain Time (Denver)
>	(UTC-7:00) Mountain Time (Phoenix)
> ("But I'm in Boulder!"  "And I'm in Tempe!"  "And *I'm* in Jackson
> Hole!").

And I’m in Lakewood! (Oh, wait. That’s right next door to Denver.)

This is what we get from a known, reliable source that offers human-readable names in English (or, importantly, 140 other languages) corresponding to tzids. Some of the names are probably not perfect for a picker. We already know that “(other)” and “(most locations)” are not always perfect either, especially when presented out of context: Other than what? What does “most” include?

We did the best we could without having to curate the list ourselves, surely a recipe for disaster.

> Not sure how you'd ask for "generic" rather than "standard" or
> "daylight" or, if you're already doing that, why it's not coughing up
> "Brasilia Time".

We’re using a standard .NET Core call that queries ICU in a Linux container, and makes a Windows call when running on Windows. There are no options to select names for standard, daylight, or generic, and I don’t know why it chooses standard by default. The ICU folks might know.

Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org

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