— Il meglio è l’inimico del bene —

On Fri, Apr 19, 2013 at 12:35 PM, Tobias Conradi <mail.2012@tobiasconradi.com> wrote:

On Fri, Apr 19, 2013 at 11:17 AM, Mark Davis ☕ <mark@macchiato.com> wrote:
>> Variable length and inconsistent country code usage:
>
> This is a misunderstanding.

Of the UN LOCODE system, on the side of CLDR designers.

> CLDR is specified to use 5 letter UN LOCODEs where they exist. Where they do
> not exist, it is specified to use a non-5-letter code, precisely so that
> they do not overlap with future UN LOCODEs.

That could have been easily achieved with 5-letter codes, as has been shown at:
http://mm.icann.org/pipermail/tz/2012-May/017974.html and
http://mm.icann.org/pipermail/tz/2012-May/017980.html

If overlap prevention the goal, then there was misunderstanding of the
UN LOCODE system on the side of CLDR.

The only way that there would be a problem for CLDR is if the UN LOCODEs could be other than 5 alphanumerics.

According to http://www.unece.org/fileadmin/DAM/cefact/locode/unlocode_manual.pdf, the UN LOCODE would be 5 letters and possibly numbers (in positions 3-5). As long as any additional CLDR identifiers did not match that, there wouldn't be an overlap.

So I don't understand your contention. Are you saying that UN LOCODEs, can in fact consist of other than 5 alphanumerics? If so, can you point us to the URL for that?

> When the codes are not 5
> letters, the first two letters have no meaning.

Except where they have. And for some from the US, even the first 4
have a meaning:
debsngn: de = Germany
gldkshvn: gl = Greenland
mxstis: mx = Mexico
rukhndg: ru = Russia
ruunera: ru = Russia
usinvev: us = US (usin = Indiana)
usnavajo: us = US
usndcnt: us = US (usnd = North Dakota)
usndnsl: us = US (usnd = North Dakota)

I should have said: When the codes are not 5 alphanumerics, the first two letters do not *necessarily* denote a country code.

> The codes are stablized, meaning that they will not change no matter what
> changes happen in the base codes. So if Hawaii leaves the US and joins
> Canada as a new province, "ushnl" would not change in CLDR even if the UN
> LOCODE changes to "cahnl" or something else.

And combining this with "When the codes are not 5 letters, the first
two letters have no meaning.", assuming that, if they have 5 letters
they /may/ have a meaning, leads to the fact that the meaning in CLDR
would be different from the meaning in the UN LOCODE system.

I don't understand what you are saying: that would only be an issue if there were overlaps.

A statement on why a country relation was not seen suitable for time
zone identifiers can be found at:
ftp://ftp.iana.org/tz/code/Theory
"Be robust in the presence of political changes."

That's fine for TZ codes. As far as CLDR is concerned, however, the main goal is to have an unambiguous, stable ID that is from 3-8 ASCII alphanumerics long and maps to TZ codes. The 3-8 ASCII limitation is imposed by BCP47, so we could not use the TZ codes unmodified. We could have chosen to simply number them, but decided that the UN LOCODEs would be a bit simpler to deal with.

--
Tobias Conradi
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10115 Berlin
Germany

http://tobiasconradi.com