Idiomatic Python - checking for zero

idioms, pep8, python

Solution

If you want to check for zero, you should use `if n == 0`. Your second expression doesn't check for zero, it checks for any value that evaluates as false.

I think the answer lies in your requirements; do you really want to check for zero, or do you want to handle a lot of situations where n might be a non-numeric type?

In the spirit of answering exactly the question asked, I think `n == 0` is the way to go.

Here's what's wrong with doing it the `not n` route:

>>> def isZero(n):
...    return not n;
... 
>>> 
>>> isZero([])
True
>>> isZero(False)
True
>>> isZero("")
True
>>>

Most people would say that this "isZero" function isn't correct.

Problem

What is the idiomatic way for checking a value for zero in Python? ``` if n == 0: ``` or ``` if not n: ``` I would think that the first one is more in the spirit of being explicit but on the other hand, empty sequences or None is checked similar to the second example.

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