On Tue, Apr 07, 2015 at 08:47:25AM -0400, Ben Hoyt wrote: > > 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)
While *in general* I agree with "handle the error case early", there are cases where "handle the normal case early" is better, and I think that this is one of them. Also, inverting the comparison isn't appropriate, due to float NANs. With the first version, foo(NAN) returns None (which I assumed was deliberate by the OP). In your version, it returns NAN. But as you say, we're now deep into the weeds... -- Steve _______________________________________________ Python-Dev mailing list [email protected] https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com