Why does removing the else slow down my code?

Question

Consider the following functions:

def fact1(n):
    if n < 2:
        return 1
    else:
        return n * fact1(n-1)

def fact2(n):
    if n < 2:
                


        

Answer 1

What is happening here is that fact2 has a hash conflict with __name__ in your module globals. That makes the lookup of the global fact2 ever so slightly slower.

>>> [(k, hash(k) % 32) for k in globals().keys() ]
[('__builtins__', 8), ('__package__', 15), ('fact2', 25), ('__name__', 25), ('fact1', 26), ('__doc__', 29)]

i.e. The same answer as for Why is early return slower than else? except that there the hash conflict was with __builtins__