[tz] Preparing to fork tzdb

Paul Eggert eggert at cs.ucla.edu
Tue Sep 21 21:13:07 UTC 2021

On 9/21/21 1:20 PM, Stephen Colebourne via tz wrote:

> Straw man. Literally no one has suggested this.

Yes, of course it's a straw argument. That's the point.

Although it'd be technically possible to require a Zone for each state 
and province in the world, it's not necessary, it would consume 
maintenance resources that are better spent elsewhere, and Zone 
proliferation would make things unnecessarily complicated for users. The 
situation for countries is similar. Admittedly there are few countries 
than states+provinces, but logically there's no difference between the 
two cases.

> If you don't like ISO countries as the basis of a rule, feel free to
> suggest something else.

My suggestion is to stick with the rules already in theory.html. They've 
worked well over the years.
> If you want to resolve the issue you need a rule that doesn't end up
> with users in Norway or Sweden requesting the time-zone for 1950 and
> getting the zone information of Germany instead.

If that's the idea, then I also need a rule that doesn't end up with 
users in Munich requesting the time zone for September 20, 1945 and 
getting the UTC offset of Berlin instead. The case for a Munich Zone is 
even stronger than the case for an Oslo Zone, as Munich has a lot more 
people (and more tzdb users) than Oslo does.

Of course this is a straw argument too; that's the point. All this stuff 
about pre-1970 timestamps is out of scope for tzdb proper, and it's 
always been out of scope.

Only politics would require us to have a Zone for every ISO country. 
Timekeeping needs don't require it. Admittedly we used to have more 
Zones, but we've never had a Zone for every ISO country and no 
timekeeping need for such a rule has ever been demonstrated.

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