need clarification on -0
Erik Max Francis
max at alcyone.com
Sat Nov 28 02:55:18 EST 2009
moijes12 wrote:
> I know the value -0 is quite meaningless and makes little sense.But I
> was just fiddling.I am unable to figure out the below result
>
>>>> -0 and True
> 0 ----------> (Why is this 0 and not say True or False)
>>>> -0 and false
> 0
>>>> -0 or True
> True
>
> Could someone please provide me some resources on how these operations
> take place.I'd wanna find it out myself
Your questions have nothing to do with -0, as it's no different from 0:
>>> 0 == -0
True
Your examples work the same way with simply 0, which is considered a
false value:
>>> bool(0)
False
>>> 0 and True
0
>>> 0 and False
0
>>> 0 or True
True
What you're seeing is simply the short-circuiting behavior of the `and`
and `or` operators; they return the last (relevant) value they
encountered before making their determination of the value of the
overall expressions. See python.org/doc for more information.
--
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
San Jose, CA, USA && 37 18 N 121 57 W && AIM/Y!M/Skype erikmaxfrancis
You'll survive / A true Darwin star
-- Des'ree
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