[tz] Metazones in the tzdb (was Re: Why did you rename Russian zone name abbreviations)

Matt Johnson mj1856 at hotmail.com
Thu Nov 3 18:47:54 UTC 2016


> Okay, "nobody" was a bit hyperbolic.  My main issue was the fact that
> most OS's C libraries (which tend to follow tzdb's lead, except for
> Windows - which has its own timezones and its own localization) don't
> seem use it, and as far as I know Python's standard library (which
> doesn't exactly have its act together with timezones in general either)
> also doesn't.

> The fact that we're talking about your project and nodatime rather than
> the basic class libraries of either C# or Java suggests that the latter
> don't use the CLDR data, or possibly even the tzdb data at all. The fact
> that they _do_ tend to provide localization of, say, month names, means
> a lot of people might not realize that they're inadequate.

Python's standard library doesn't have it, but there's Babel, which does have time zone support from CLDR
http://babel.pocoo.org/

I believe Java has been using it for quite some time now.  AFAIK, TimeZone.getDisplayName calls into ICU4J, which uses CLDR data.
https://docs.oracle.com/javase/8/docs/api/java/util/TimeZone.html#getDisplayName--


Anyway, I agree that it's not likely to be found in low-level C libraries, but that doesn't mean it's not in use.

My person experience - I've found most of the time zone long names in CLDR to be adequate, but their support for time zone abbreviations is somewhat patchwork.  They have lots of them, but they don't cover the world.

As far as locale, In general, they seem to only exist in English, and occasionally in French. (ex, "HNE", or "HEE" for French-Canadian Eastern Time abbreviations.  Are these used for real in Canada?  Who knows.)

They also seem to think that abbreviations should be only used locally, such as "BST" only being used by British English. One would think that if an American was talking about DST in the UK they would also use the term "BST", but no:
http://unicode.org/cldr/trac/ticket/8498

Honestly, I don't think pointing folks at CLDR as a better source of time zone abbreviations is very useful.  CLDR might be able to host such data, but it just doesn't seem to be curated to the same degree that other things are.

</rant>


More information about the tz mailing list