[Python-Dev] PEP 8 update

[Ben Hoyt]

> My own preference would be:
>
>     def foo(x):
>         if x >= 0:
>             return math.sqrt(x)
>         return None

Kind of getting into the weeds here, but I would always invert this to
"return errors early, and keep the normal flow at the main indentation
level". Depends a little on what foo() means, but it seems to me the
"return None" case is the exceptional/error case, so this would be:

def foo(x):
    if x < 0:
        return None
    return math.sqrt(x)

The handling of errors is done first, and the normal case stays at the
main indentation level. Is this discussed in style guides at all? I
don't see anything directly in PEP 8, but I might be missing
something.

Oh wait, I just noticed this is exactly how Guido has it in his PEP
addition with the definition of bar(). :-|

-Ben