[Python-Dev] datetime +/- scalars (int, long, float)?

2002年3月05日 21:41:31 +0100

Guido van Rossum wrote:
>> > > [MAL]
> > > You should forget about DST if you want a sane
> > > implementation. Same for leap seconds.
>> I think I want to introduce a new concept, closely related to local
> time, that I'll dub "naive time" for now. In naive time, there is no
> timezone and there is no DST. To compensate for DST, you have to
> manually change the clock, which is an action outside the system,
> unknown to the system, and irrelevant to the working of the system.
> Ditto to change time zones.
>> Naive time is what you see on your watch or your Palm organizer
> (apparently not on PocketPC or Windows/CE though, which are timezone
> aware). A day is always 24 hours, and the clock always shows local
> time. When the DST jump happens, you lose or win an hour but you do
> your best to pretend it didn't happen, by going to bed a little
> earlier or by partying a little longer (or any other activity that
> causes memory loss :-).
>> My Palm has no problem keeping track of appointments in different
> timezones: when I have a meeting in San Francisco at 11am, I enter it
> at 11am, and when I fly there, I move the Palm's clock three hours
> back. Naive time adapts to local time -- time flies (or stands still)
> when you're in an airplane crossing timezones.
>> Naive time calculations are easier than local time calculations,
> because they don't have to worry about DST. You only have to be
> careful when converting between naive time and UTC (or anything else
> that has a concept of timezone).

Just to let you know: you are slowly narrowing in on mxDateTime ;-)
(the naive type is pretty much what I have implemented as 
DateTime object).
-- 
Marc-Andre Lemburg
CEO eGenix.com Software GmbH
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