checking if a list is empty

Steven Howe howe.steven at gmail.com
Wed May 11 18:09:51 EDT 2011


On 05/11/2011 02:47 PM, Steven D'Aprano wrote:
> On Wed, 11 May 2011 20:13:35 +0100, Hans Georg Schaathun wrote:
>
>> One principle of object oriented programming is to bestow the objects
>> with properties reflecting known properties from the domain being
>> modelled.  Lists do not have truth values in the application domain
> Yes they do. Empty lists are nothing, ergo false, and non-empty lists are
> something, ergo true.
>
>
> >>>  a=[]
> >>>  if a:
> ...     print 'Yes'
> ...
> >>>  a=[1]
> >>>  if a:
> ...     print 'Yes'
> ...
> Yes

Cool; I'd never of thought to try that method to determine if a list was 
empty. I usually test it's length.
This looks faster.





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