checking if a list is empty

[Prasad, Ramit]

> I don't mean to insult anyone, but I've heard and read all the arguments against Python's truth-testing, and they
>don't impress me in the slightest. Most of them strike me as silly. The only argument that carries any weight to me is
>one which I haven't seen anyone raise:

>"if x:" turns something which arguably could have been a mistake ("oops, I forgot to write the condition!") into valid
>code.

The only problem I have had with the "if x:" notation is when I have values that might be empty lists, empty strings, None, or a boolean value being returned from the same source. But this is probably an instance when a good programmer would explicitly check the type instead of the naive "if x:" notation.

On the other hand, as a fairly n00b Python (and n00b Perl) developer, I find the notation "if not x:" to be far more English readable than "if x==None or len(x)== 0 or x==0 or bool(x):" (or some derivative/combination of those). 



Ramit

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