Checking if elements are empty

Neil Cerutti horpner at
Mon Sep 10 15:06:35 CEST 2007

On 2007-09-08, Wildemar Wildenburger <lasses_weil at> wrote:
> Lawrence D'Oliveiro wrote:
>>>>> if y[0]:
>>>> Not a good idea.
>>> Why not?
>> Because there is a situation where your version of the test
>> will fail even if the first element of y is non-null.
> Such as? Seriously people, a little more verbosity wouldn't
> hurt here. This isn't a mystery game.

>>> if "": True
>>> if 0: True
>>> if []: True
>>> if {}: True
>>> if None: True

That's may not be all the possibilities. Lots of Python objects
can evaluate to false in a boolean context.

Neil Cerutti
The Pastor would appreciate it if the ladies of the congregation would lend
him their electric girdles for the pancake breakfast next Sunday morning.
--Church Bulletin Blooper

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