0 == False but [] != False? - comp.lang.python

Message from discussion 0 == False but [] != False?
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Rajarshi wrote:

> This is a slightly naive question, but I know that 0 can be used to
> represent False. So
> 
>>>> 0 == False
> True
> 
> But, I know I can use [] to represent False as in
> 
>>>> if not []: print 'empty'
> ...
> empty
> 
> But then doing the following gives a surprising (to me!) result
> 
>>>> [] == False
> False
> 
> Could anybody point out why this is the case?

Because "representing False" (i.e., being false) and "being the same as 
False" are not the same thing.

	if x:
	   ...

is not the same thing as

	if x == True:
	    ...

it's the same as

	if bool(x):
	    ...

So a more meaningful comparison of your two tests are:

 >>> bool(0) == bool(False)
True
 >>> bool([]) == bool(False)
True

-- 
Erik Max Francis && m...@alcyone.com && http://www.alcyone.com/max/
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