[tz] Dropping iso3166.tab

Guy Harris guy at alum.mit.edu
Thu May 23 08:59:56 UTC 2013


On May 23, 2013, at 1:02 AM, "Tim Thornton" <tt at smartcomsoftware.com> wrote:

> My thoughts are as follows, for what it's worth:
> - Time zones apply to an area, not just the (near) point of a city, so at some stage. This may be done in software, e.g. the country code of the tz database mapping to a GIS boundary, or by the user associating London with UK. Whilst defining the geography of the boundary is outside of the tasks of the tz list, I think it is necessary to be able to have some sort of association from point to area'

I assume there was intended to be some more text after "so at some stage" and before the period, perhaps "...somebody needs to be able to associate a time zone with the boundary of the area to which it applies".

That is what the OS X System Preferences "Date and Time" item seems to do in the "Time Zone" pane; I think at least some other OSes offer a similar mechanism.  I don't know whence they get the boundary information.

> - There has been some talk about geolocation or getting data from a server. I don't think we can assume this is available, and tz data should stand alone without this

At least my talk about geolocation wasn't assuming it's available, it was just suggesting that, in cases where it *is* available, that's the best default mechanism to use to select a time zone (i.e., don't even force the user to pick a region on a map, much less pick one of the arbitrary strings the tz database assigns to zones).

If it's not available, obviously, that can't be done.

> - I think part of the intensity of the debates on various decisions has been that the rules are not well documented and transparent, but are held in a combination of files, newsgroup archives, and people's joint knowledge. If the rules are documented more rigorously and in one location, then any debate can be focussed first on does the data follow the rules and, if there is still an issue, should we change the rules for all locations instead of on a case by case basis. This will hopefully be more objective and less emotive than just "city a should be in country x and not y because it follows the beliefs of myself and some others" which is what it generally boils down to.

Sounds good.


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