Implicit conversion to boolean in if and while statements

Steven D'Aprano steve+comp.lang.python at pearwood.info
Mon Jul 16 10:05:16 CEST 2012


On Sun, 15 Jul 2012 19:41:34 -0700, Ranting Rick wrote:

> Short circuitry is a powerful tool! But why the heck would your
> sequences ever be None? Are you using None as a default? And if so, why
> not use an empty sequence instead ([], {}, "")?


Mostly for explicitness. I want to be able to say that there is 
*explicitly* no seq, not merely that it happens to be a list which right 
now is empty but later might not be. Using None for missing values is 
idiomatic Python.

You should approve, if only for the sake of consistency: None is meant to 
be used as "no such value", and that's exactly how I am using it, even at 
the cost of my convenience when writing the code.


-- 
Steven



More information about the Python-list mailing list