On 07/24/2012 01:28 PM, Marc-Andre Lemburg wrote:
> I would be interested in an actual use case for this.

Alice has a dataset with nanosecond granularity. He wants to make a
python library to let Bob access the dataset. Nowadays Alice has to
implement her own time class losing all the flexibility of the datetime
module. With this enhancement she can provide a library that just uses
the standard python datetime module. Her library will get the needed
time format, including nanoseconds.

Many python sql libraries, like the one in django e the one in web2py,
relay on datetime objects for time representation. Bob has a web2py
website that has some data with nanosecond granularity. Nowadays Bob has
to store this data as a string or a long number without the ability to
use the powerful datetime module. With this enhancement Bob doesn't need
to build or learn another interface, he can just use the datetime module
using microseconds or nanoseconds as needed.

Google search for "python datetime nanoseconds" shows more than 141k
results:
https://www.google.com/search?sourceid=chrome&ie=UTF-8&q=python+time#hl=en&biw=1615&bih=938&sclient=psy-ab&q=python+datetime+nanoseconds&oq=python+datetime+nanoseconds

So this is definitively a requested feature. And as soon as technology
evolves more people will ask for it.

I imagine something like:

import datetime
nano_time = datetime.datetime(year=2012, month=07, day=24, hour=14,
minute=35, second=3, microsecond=53, nanosecond=27)

in case you need nanosecond granularity. if you don't need it just skip
the nanosecond part and the module works like it's now. Of course
strftime format should be updated to support nanoseconds.

I can write a patch if some dev can maybe review it.

Before someone takes the datetime source code and starts a third part
module that supports nanoseconds, I think this enhancement has almost
null impact in existing code and makes the datetime module even more
powerful. It's up to the Cpython admins to decide between maintaining
datetime module up to date with new needs or let third part modules take
care of those lacks.

Best Regards,
-- 
Vincenzo Ampolo
http://vincenzo-ampolo.net
http://goshawknest.wordpress.com