[Datetime-SIG] The BDFL's take

[Lennart Regebro]

On Wed, Jul 29, 2015 at 5:50 PM, Alexander Belopolsky
<alexander.belopolsky at gmail.com> wrote:
> The problems you gave, are perfectly solvable using current Python 3 standard
> library.

No, it isn't, as the Python 3 standard library does not contain
real-life timezone implementations.

> For some reason you insist on solving them using third party
> tools that are not designed for those particular tasks.

The third party tool is designed to handle real-life timezone
implementations, and implements them precisely the way the datetime
designers intented. It does exactly what Tim says it should do.

> You want to know what was the local time in New York one astronomical hour
> after  2014-11-02T01:30-0400 - set TZ=America/New_York and do this:
>
>>>> t = datetime.strptime("2014-11-02T01:30-0400", "%Y-%m-%dT%H:%M%z")
>>>> u = (t+timedelta(hours=1))
>>>> u.astimezone().strftime("%Y-%m-%dT%H:%M%z")
> '2014-11-02T01:30-0500'

>>> t = datetime.strptime("2014-11-02T01:30-0400", "%Y-%m-%dT%H:%M%z")
ValueError: 'z' is a bad directive in format '%Y-%m-%dT%H:%M%z'

Nope, didn't work. Did you mean uppercase Z?

>>> t = datetime.strptime("2014-11-02T01:30-0400", "%Y-%m-%dT%H:%M%Z")
ValueError: time data '2014-11-02T01:30-0400' does not match format
'%Y-%m-%dT%H:%M%Z'

Probably, but it still didn't work.

> What do you see lacking in this solution?

Please test your examples before you paste them, I have no idea what
you are trying to do.