[Python-ideas] datetime: Support infinity

[Chris Barker]

On Wed, Jan 28, 2015 at 6:55 PM, Yawar Amin <yawar.amin at gmail.com> wrote:

> Cool, the comparison operator logic looks very similar to mine:
>
> https://groups.google.com/d/msg/python-ideas/G3jeWoa6h14/ELpDLFu28QcJ
>
>
Did you get it to work both ways? i.e.

datetime.neg_inf < datetime.now()

and

datetime.now() > datetime.neg_inf

I had trouble with that, because the regular datetime doesn't know how to
compare itself to a neg_inf object.


> I believe the ideal design is the following type hierarchy:
>
>     datetime_base
>       datetime_neg_inf
>       datetime_pos_inf
>       datetime
>
> But in the interests of pragmatism, I think this one can be made to
> work:
>
>     datetime
>       datetime_neg_inf
>       datetime_pos_inf
>

yup -- should work.

and you could add class methods to the datetime object, so you could do:

datetime.neg_inf()
and
datetime.pos_inf()


> The
>
advantage to this is that we don't have to switch everything over to
> using a new derived type--just use the normal datetime for the majority
> of cases where we don't need inifinity dates.
>

And it could be a third part package, too. -- particularly good for
backward compatibility.

-Chris


-- 

Christopher Barker, Ph.D.
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