[Python-Dev] TZ-aware local time

[Nick Coghlan]

On Wed, Jun 6, 2012 at 1:14 PM, Guido van Rossum <guido at python.org> wrote:
> You can try to enforce this, but users will ignore it, and happily
> represent local time as UTC. I've seen people do this with POSIX
> timestamps too -- use the UTC conversions between timestamps and time
> tuples, and yet use time tuples to represent local time (the
> timestamps are stored because integers are easier to store). And yes
> they get in horrible trouble around DST and they don't understand why.
> But they still do it.
>
> I think it's better to give users the rope they want than to try and
> prevent them from hanging themselves, since otherwise they'll just use
> the power cords as ropes and electrocute themselves.

Agreed, I'm just asking that the particular brand of rope be the
assumption that naive timezones are implicitly UTC and allowing
transparent interoperation according to that assumption. If someone is
just using them to represent local time, and only have to deal with
local time in one location, then they'll still mostly be fine (setting
aside DST problems).

If naive times and tz-aware times can natively interoperate, then it
provides a path towards making more of the stdlib tz-aware by default
(such as returning objects with the timezone set to UTC).

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia