[tz] Proposal - territorial coverage of an IANA zone - define, document, enforce

Tobias Conradi tobias.conradi at gmail.com
Thu Jul 10 22:13:03 UTC 2014

1) Define what territory an IANA zone covers
2) Include the definition in the documentation
3) Enforce the definition

If there would be a definition that territories that use different
abbreviations shall have different zones, then the merger

On Thu, Jul 10, 2014 at 8:41 PM, Paul Eggert <eggert at cs.ucla.edu> wrote:
> Alan Barrett wrote:
>> To the best of my knowledge, most other African countries that share the
>> same UTC offset do not use the abbreviation "SAST"
> Thanks for catching this; this was indeed an error in the merge,

would have violated 3). Is it really true, that starting 2014-07-10
IANA zones are created based on acronym observation?

Also "coincidence" as in

On Thu, Jul 10, 2014 at 8:39 PM, Paul Eggert <eggert at cs.ucla.edu> wrote:
> This is a good point, and in some cases in hindsight I went too far in
> merging zones that were coincidentally the same
would need definition, if one really wants to base territorial
extension of IANA zones on such a vaguely defined concept which can
lead to decision that may look arbitrary.

And arbitrary seems to be the other rule:
> This is not a question about optimizing the implementation; it's a question
> of having the tz data reflect our knowledge as accurately as the current
> format allows.
The current format allows to have at least one zone per post-1970 ISO
3166 country and having this would allow to more accurately "reflect
our knowledge", namely for abbreviations and for laws.

Laws are the main source for observation of a specific standard time
in any country. So one could think the territory covered by an IANA
zone would at least be a subset of the territory of exactly one
jurisdiction named a country in ISO 3166.

If acronym observation and "coincidence" are the basis of zoning, I
propose to include that in the documentation.

Tobias Conradi
Rheinsberger Str. 18
10115 Berlin


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