Re coming Russian-Belarusian-Ukrainian timezone change

Tobias Conradi tobias.conradi at
Fri Sep 23 09:06:09 UTC 2011

> On 09/22/2011 10:45 PM, Tobias Conradi wrote:
>> The proposal  EEFT keeps the EE of EET and EEST. It is also more in
>> line with existing naming rules in the Theory file, quoting Theory: ...

On Thu, Sep 22, 2011 at 10:13 PM, Yury Tarasievich
<yury.tarasievich at> wrote:
> I'd concur with Paul Eggert and suggest forego building a theory for this.
That FT means forward time was emailed to the tz-list, this act could
be regarded as theory building. But I wouldn't regard writing the
theory down as building one.

Since it was you who proposed that FT means forward time, did you with
your last email intend to withdraw your proposal?

> This is a clear once-only case, and should be discussed as such, I think.
I am one of those that cannot predict the future.

If one writes the meaning into the Theory file, it can be marked there
as currently only used by EEFT, but the the next time such a situation
of "forward time" occurs people can find it. Some people may have all
the theory in their head, but there it is in danger of getting changed
without notice. If the theories behind the tz database are written
down into the Theory file, at least other people can check the
theories and find any changes by using diff tools.

My reworded proposal for the Theory file is:

All abbreviations end in "T". Some generic endings are:
- MT for mean time (e.g. GMT),
- ST for summer time (e.g. BST, CEST),
- DST for double summer time (e.g. BDST, MDST)
- FT for forward time (permanent summer time, only used for EEFT).

The strings are also used in zone abbreviations without
having these meanings,
e.g. AFT = Afghanistan Time, ALMT = Alma-Ata Time,
IST = Indian Standard Time.

Zones that use ST to mean standard time commonly use
DT to mean daylight [saving] time, e.g. EST, EDT in North America.

Tobias Conradi
Rheinsberger Str. 18
10115 Berlin

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