[Datetime-SIG] What's are the issues?

[Chris Barker]

On Tue, Jul 28, 2015 at 6:43 PM, Chris Angelico <rosuav at gmail.com> wrote:

What if the existing timedelta is left as-is, and a new calendardelta
> type is introduced? Instead of folding everything down to a simple
> microsecond count, it would retain the exact values it was given,


sure -- that would be one way to do it -- maybe  good way. But it would be
a lot more complicated than just keeping days. Lots to hash out for API and
functionality at the corner cases (the old what's one year after Feb 29th?
kinds of questions)


> When you add a
> calendardelta to an aware datetime, it performs what you're describing
> as calendar arithmetic,


actually, no reason you couldn't do calendar manipulations on naive
datetimes, too (they wouldn't get any ugly DST issues, but otherwise the
same). One reason I don't like calling the arithmetic naive or not....



> adding
> calendardelta(days=1) would never affect the hour/minute/second shown,
> unless it would otherwise create an illegal time.


exactly -- all those corner cases would need to be worked out.

-Chris

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Christopher Barker, Ph.D.
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