[Python-Dev] redux: fractional seconds in strptime

[Alex Martelli]

On 2005 Jan 14, at 10:36, Skip Montanaro wrote:

>
>     Brett> The problem I have always had with this proposal is that the
>     Brett> value is worthless, time tuples do not have a slot for 
> fractional
>     Brett> seconds.  Yes, it could possibly be changed to return a 
> float for
>     Brett> seconds, but that could possibly break things.
>
> Actually, time.strptime() returns a struct_time object.  Would it be
> possible to extend %S to parse floats then add a microseconds (or 
> whatever)
> field to struct_time objects that is available by attribute only?  In 
> Py3k
> it could worm its way into the tuple representation somehow (either as 
> a new
> field or by returning seconds as a float).

+1 -- I never liked the idea that 'time tuples' lost fractions of a 
second.  On platforms where that's sensible and not too hard, 
time.time() could also -- unobtrusively and backwards compatibly -- set 
that same attribute.  I wonder if, where the attribute's real value is 
unknown, it should be None (a correct indication of "I dunno") or 0.0 
(maybe handier); instinctively, I would prefer None.

"Available by attribute only" is probably sensible, overall, but maybe 
strftime should make available whatever formatting item[s] strptime may 
grow to support fractions of a second; and one such item (distinct from 
%S for guaranteed backwards compatibility) should be "seconds and 
fraction, with [[presumably, locale-specific]] decimal point inside".


Alex