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Re: TimeZones and politics Re: How to tell (in advance) if adate-time is ambiguous?

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Eric Brine
July 12, 2017 16:40
Re: TimeZones and politics Re: How to tell (in advance) if adate-time is ambiguous?
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On Wed, Jul 12, 2017 at 11:07 AM, Binarus <> wrote:

> On 11.07.2017 20:50, Bill Ricker wrote:
> > On Tue, Jul 11, 2017 at 4:07 AM, Binarus <> wrote:
> >>
> >> On 10.07.2017 20:14, Eric Brine wrote:
> >>> I don't understand the conditions. The law determines when the
> switching
> >>> of offsets from UTC happen, not some person. The switch doesn't happen
> >>> at 08:48:27 am in Chicago; it happens at 2am.
> >>
> >> This point of view is a bit U.S. centric. Indeed, you are describing how
> >> it *should* be, but
> >
> > We tend to use the timezone nearest us for examples because we're less
> > likely to be wrong and thence get dragged into discussing the example
> > instead of the concept.
> >
> Well, first of all, I did not want to insult or even criticize anybody.
> Please forgive me if my wording even made the slightest impression of
> doing so - regrettably, I am not a native English speaker.
> Actually, I am feeling the highest respect towards the experts who are
> helping with the time zone database updates, are bringing them to a
> machine readable form and are writing software modules which are dealing
> with the overwhelming bunch of time calculating oddities in an
> impressive manner. I am really very grateful for that and can't thank
> those volunteer experts enough.
> I just wanted to say that the statement "... the change happens at 2:00
> in Chicago ... " might not be sufficient for my case because I am trying
> to write a web application which deals with date and time calculations
> in local time zones around the world, and that I'd like the application
> to behave well (as far as possible) even in the weirdest cases.

Chicago was the OP's example. I'm not even American.

My point was that the time of change is not up to debate; it's in the time
zone db, so the information is available. It's not as arbitrary as I
thought the OP made it sound.

Others have pointed out this the time zone db can change with very little
notice since TZ definitions can change with very little notice.

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