[tz] Time zone selection

[Gilmore Davidson]

> On 19 Apr 2016, at 4:58 am, Guy Harris <guy at alum.mit.edu> wrote:
> 
> The OS X selector lets you select either by
> 
> 	1) dragging a blue dot to the appropriate location - it shows a world map, with some region containing the dot highlighted (it's not a tzdb zone, as it includes more than one tzdb zone - Deborah, any idea what those regions are?);

I’m happy for Deborah to correct me, but as far as I can tell the highlighted regions are simply zones grouped by UTC offset, ignoring DST. For example, Sydney, Brisbane and Vladivostok all get grouped in a single UTC+10 band.

> 	2) selecting a nearby city from a combo box (you can either select an item or type a name; it appears to do a fuzzy search of some sort when you type a name - "Cowabunga" found Cwmbran in the UK - but it has a limited number of cities, so "Weed" found Weert in the Netherlands rather than Weed in California).

An interesting difference is in the icloud.com web version of the picker. It’s a much smaller map, so presumably to account for mis-clicks, any selection of a city in a highlighted region also displays a dropdown menu to choose between the different major cities in that same UTC offset.

Selecting the UTC-7 band (using English language) gives options of “Calgary - Canada (Mountain Time)”, “Denver - U.S. (Mountain Time)”, “Phoenix - U.S. (Mountain Time)” and “Salt Lake City - U.S. (Mountain Time)”.