[Python-Dev] PEP 410, 3rd revision, Decimal timestamp

[Steven D'Aprano]

Martin v. Löwis wrote:
>>>  * Ruby (1.9.3), the `Time class <http://ruby-doc.org/core-1.9.3/Time.html>`_
>>>   supports picosecond (10\ :sup:`-12`)
>> We must do better than Ruby: support arbritrary precision! :-D
> 
> Seriously, I do consider that a necessary requirement for the PEP (which
> the Decimal type actually meets). I don't want to deal with
> this issue *again* in my lifetime (now being the second time),
> so it's either arbitrary-precision, or highest-possible precision.
> When I was in school, attoseconds (as) where the shortest named
> second fraction. Today, it seems we should go for yoctoseconds (ys).
> There is an absolute boundary, though: it seems there is no point in
> going shorter than the Planck time (5.4 * 10**-44).


That is an implementation detail. Python implementations in other universes 
may not have that limitation.

Besides, if any of the speed of light c, gravitational constant G, Planck's 
constant h, or pi change, so will Planck time. Perhaps they should be 
environment variables?


Not-quite-sure-how-seriously-you-intend-supporting-yoctoseconds-ly y'rs,


-- 
Steven