What is the scope of a defaulted parameter in Python?

Question

When you define a function in Python with an array parameter, what is the scope of that parameter?

This example is taken from the Python tutorial:

de         


        

Answer 1

There's even less "magic" than you might suspect. This is equivalent to

m = []

def f(a, L=m):
    L.append(a)
    return L

print f(1)
print f(2)
print f(3)

m is only created once.