[Datetime-SIG] Are there any "correct" implementations of tzinfo?

Alexander Belopolsky alexander.belopolsky at gmail.com
Mon Sep 14 23:23:34 CEST 2015

On Mon, Sep 14, 2015 at 4:54 PM, Random832 <random832 at fastmail.com> wrote:

> But anyway, none of this is actually relevant to my claims about how the
> times near "fall back" transitions (i.e. with different fold values)
> should be sorted.

Current behavior for gap times is relevant because it shows that you do get
surprising results when you step out of the naive time model.  The gap
times can be created now and they violate astimezone(utc) monotonicity.
PEP 495 allows more times that are outside of the naive time model: fold=1
times in the fall-back fold.  It is unavoidable that astimezone(utc) is
non-monotonic in this case as well.  After all, why does it concern you
more than the non-monotonicity of  astimezone(local)?

I wasn't at any point proposing *actually* converting
> to UTC as part of the mechanism for comparing times.

In this case what were you *actually* proposing?

> Just that having
> times near "fold" points ordered in any other way would be surprising
> and unreasonable.

"Other" than what?  In the previous sentence you said that converting to
UTC to compare was not your proposal.  Please let us know what your
proposal is rather than what it isn't.
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