On 05.03.2014 23:38, Donald Stufft wrote:
On Mar 5, 2014, at 5:35 PM, M.-A. Lemburg
wrote: On 05.03.2014 23:16, Ben Finney wrote:
"M.-A. Lemburg"
writes: I don't know what all the fuzz is about. There are lots of types in Python that evaluate to False in certain corner cases, e.g. "", (), [], {}, 0, 0.0, 0j, None, etc.
datetime.time(0,0,0) is just another one :-)
The salient difference is:
With the former set, they all embody concepts of either “empty” or “zero magnitude”. They strongly connote “not there” within their domain of values, hence map well to Boolean false.
With ‘datetime.time’ there is no equivalent: midnight is not special in the way “empty” or “zero magnitude” are. Midnight is an arbitrary point on a continuum, and is not a “not there” value.
This is true in a date/time continuum, but not true if you regard time as "time of day". In the latter interpretation, the day starts at midnight, so the day is "not there" yet at midnight.
The day is absolutely here at midnight. Midnight isn’t some void where time ceases to exist.
No, but midnight starts the day, just like 0 starts the positive real numbers (itself not being positive) :-)
It should not be Boolean false any more than any other time.
Just like with most interpretations, you can just as easily find one which implies the exact opposite.
It's all smoke and mirrors anyway :-)
Perhaps Tim just wanted to be able to make float(time(0,0,0)) return 0.0 seconds some day. That's what mxDateTime does for time values.
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2014-04-09: PyCon 2014, Montreal, Canada ... 35 days to go ::::: Try our mxODBC.Connect Python Database Interface for free ! :::::: eGenix.com Software, Skills and Services GmbH Pastor-Loeh-Str.48 D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg Registered at Amtsgericht Duesseldorf: HRB 46611 http://www.egenix.com/company/contact/