On Sep 18, 2013, at 1:06 AM, Lester Caine <lester@lsces.co.uk> wrote:
I'm trying to help with the idea of the addition of 'thousands' of timezones, and in the end if there is evidence for thousands in the USA then they simply need documenting anyway!
Perhaps they do, but whether that document needs to take the form of thousands of extra tzids is another matter. If they do, we should definitely give packagers of the tzdb, such as OS vendors, the option of *not* providing those thousands of extra tzids.
I would still like to tidy up 'backward' as well to actually contain dates that a particular alias was used from 'officially'.
As far as I'm concerned, "backward" should contain only links provided for backwards-compatibility reasons when a tzid name change occurred, e.g. Link America/Halifax Canada/Atlantic Link America/Winnipeg Canada/Central Link America/Regina Canada/East-Saskatchewan Link America/Toronto Canada/Eastern Link America/Edmonton Canada/Mountain Link America/St_Johns Canada/Newfoundland Link America/Vancouver Canada/Pacific Link America/Regina Canada/Saskatchewan Link America/Whitehorse Canada/Yukon Link America/Anchorage US/Alaska Link America/Adak US/Aleutian Link America/Phoenix US/Arizona Link America/Chicago US/Central Link America/Indiana/Indianapolis US/East-Indiana Link America/New_York US/Eastern Link Pacific/Honolulu US/Hawaii Link America/Indiana/Knox US/Indiana-Starke Link America/Detroit US/Michigan Link America/Denver US/Mountain Link America/Los_Angeles US/Pacific and, I think: Link America/Havana Cuba Link Africa/Cairo Egypt Link Europe/Dublin Eire Link Europe/London GB Link Asia/Hong_Kong Hongkong Link Atlantic/Reykjavik Iceland Link Asia/Tehran Iran Link Asia/Jerusalem Israel Link America/Jamaica Jamaica Link Asia/Tokyo Japan Link Pacific/Kwajalein Kwajalein Link Africa/Tripoli Libya Link America/Tijuana Mexico/BajaNorte Link America/Mazatlan Mexico/BajaSur Link America/Mexico_City Mexico/General Link Pacific/Auckland NZ Link Pacific/Chatham NZ-CHAT Link America/Denver Navajo Link Asia/Shanghai PRC Link Europe/Warsaw Poland Link Europe/Lisbon Portugal Link Asia/Taipei ROC Link Asia/Seoul ROK Link Asia/Singapore Singapore Link Europe/Istanbul Turkey which are, I think, backwards-compatibility links introduced with the naming convention change. The only historical information associated with them relates to the history of the tzdb *itself*, and that's not of any use to people using the tzdb. There are also backwards-compatibility links introduced due to city name changes, e.g. not using "foreigner's" names for the city, e.g. Link Africa/Asmara Africa/Asmera Link Asia/Kolkata Asia/Calcutta Link Asia/Chongqing Asia/Chungking Link Asia/Dhaka Asia/Dacca Link Asia/Kathmandu Asia/Katmandu Link Asia/Macau Asia/Macao The only historical information associated with them is the date when the old names were deprecated, which has nothing to do with the history of time zones. Some links in "backwards" should perhaps be moved to other files. (The politically-sensitive links might fall into that category.)