[tz] 'Australia/Canberra' time zone?
john.pye at anu.edu.au
Sun Nov 24 11:35:01 UTC 2019
Thank you both for the clarification. I understand better now how
locations are decided for inclusion in tzdata; it is not at all to do
with size/importance as I had assumed, but about maintaining a minimal
set of zones with a single representative city from each one selected to
be used as the label. Software should never have to ask a 'regular
person' what their timezone is, but instead to ask for their location,
and then make use of some kind of location-to-timezone lookup routine.
On 24/11/19 5:35 am, Guy Harris wrote:
> On Nov 23, 2019, at 1:10 AM, Paul Eggert <eggert at cs.ucla.edu> wrote:
>> On 11/22/19 10:06 PM, John Pye wrote:
>>> What is the basis for deciding
>>> which cities are included or excluded from the database? Does being the
>>> national capital, and the major city in its own state/territory warrant
>>> inclusion, or is there another criterion?
>> The latter. See <https://data.iana.org/time-zones/theory.html#naming>.
> In particular, this means that people shouldn't look for *their* city, or for the major city nearest to them, if they're looking for the name to use in the tzdb ID setting they want. A lot of people in California, for example, will fail to find America/San_Francisco or America/San_Jose in the database, they'll only find America/Los_Angeles even though they're a lot closer to San Francisco or San Jose than they are to Los Angeles.
> User interfaces for selecting a time zone should not rely on the set of tzdb IDs being a comprehensive list of cities.
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