Tobias Conradi mail.2012 at tobiasconradi.com
Fri Apr 12 14:57:35 UTC 2013

On Fri, Apr 12, 2013 at 4:40 PM, Tim Parenti <tim at timtimeonline.com> wrote:
> On 12 April 2013 04:45, Tobias Conradi <mail.2012 at tobiasconradi.com> wrote:
>> D for %s never means anything else than 1:00 saving.
> Within the current tz database, sure, that is presently the case.  But this
> is not necessarily the case within ACTUAL practice;
Sure, actual practice in the IANA time zone database.

> "D" could conceivably be
> used to refer to a DST offset of any amount, since it is still "daylight
> saving time", just of a different amount.
Against actual practice in the IANA time zone database, deteriorating
usability for those that rely use systematization.

> I am not making the argument here that the terminology is used this way in
> Australia/Lord_Howe; only that if it is, then LHDT is a perfectly suitable
> (and indeed, preferred) abbreviation for UTC+10:30+0:30 as observed there in
> the summer.
Why? For other regions the database does not care at all about local
usage and will certainly fail in bilingual environments.

>  To be clear, I haven't seen any evidence either way, but I
> don't particularly believe any residents of Lord Howe Island would call it
> "Lord Howe half-daylight time", because to them, half an hour is a full
> transition.
Does that matter?

> Granted, this has not always been the case (see four summers from 1981–1982
> to 1984–1985), but I suspect residents understood it as a change to
> "daylight saving time" itself, while still referring to it in the same way.
> Whatever the case, we should reflect the terminology in use, and not aim for
> anything more.
Oh, why that? And how can that be applied to abbreviations for newly
created zones?

> On 12 April 2013 08:38, <random832 at fastmail.us> wrote:
>> You are inferring a systematism where non exists.
> Precisely.
Contradicting your own "Within the current tz database, sure, that is
presently the case. "

> On 12 April 2013 04:22, Tobias Conradi <tobias.conradi at gmail.com> wrote:
>> > We are not inventing anything new
>> It has been proven you do in the scope of the DB.
> I have not been part of this project for very long, but I believe most of
> the "invented" abbreviations have been simply to fulfill POSIX requirements
> where no commonly-used English terminology previously existed.
POSIX requirements for abbreviations can be fulfilled without English
terminology. E.g. WIT could mean Waktu Indonesia Timur (Eastern
Indonesian Time) instead of IANA used English Western Indonesia Time.

The English speaking countries largely get their way through with
locally used abbreviations, whilst needs and wishes of others are

Tobias Conradi
Rheinsberger Str. 18
10115 Berlin


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