On Wed, 15 Aug 2012, David Patte ₯ wrote:
Thanks for the research and spreadsheet. It is very useful.
Being Canadian, I am intruiged by Ottawa, which is the capital of Canada, the second largest city in Ontario, and the fourth largest in Canada. It seems that since 1970, Ottawa and Toronto and Montreal have followed the same timezone/saylight saving rules, but prior to that, Ottawa and environs was likely more in sync with Montreal's daylight saving rules than Toronto's rules for proximity and commercial reasons. As well, Montreal, not Toronto, was the largest city in Canada until about 1975.
So, as far as I understand the rules, Ottawa does not require a link in tz at this time - but if a link for capitals is ever added in tz - the preferred link for Ottawa should probably be Montreal, not Toronto.
This IMO partly illustrates why we should not make any links. The idea is that TZ identifiers are unique and *stable*. In the list, there are plenty of IDs with as comment "Used to be the capital until 19xx". In the case of Ottawa and Montreal, if you add a link, and then Quebec decides to split off Canada and choses to use Europe/Paris (which is not that far sought ;-) ) then you end up having a non-stable ID as Ottawa and Montreal no longer can be linked. The issue of Beijing/Shanghai has been discussed many times, and I feel that we shouldn't revisit it anymore. TZIDs are not meant to be used in userland - this is document. Unicode's CLDR (http://unicode.org/repos/cldr-tmp/trunk/diff/summary/de.html, search for "AT/Vienna", "Europe/London" f.e., as well as http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/zone_tzid.html) already provide user-visable names for many languages and timezones - and this would be the perfect place for all sorts of display rules. cheers, Derick -- http://derickrethans.nl | http://xdebug.org Like Xdebug? Consider a donation: http://xdebug.org/donate.php twitter: @derickr and @xdebug