从python中的内部函数对象获取外部函数的名称

Question

Assume a nested function in python, where outer denotes the outer function and inner denotes the inner function. The outer function provides parametrization of the inner function and returns an instance of this parametrized function.

I want to obtain the name of the outer function, given an instance of the inner function which is returned by the outer function. The code is as follows:

def outer(a):
    def inner(x):
        return x*a
    return inner
p = outer(3)
print p  # prints inner
print p(3)  # prints 9

How can I print the name of the outer function, ie outer , given only p ? Thanks!

Answer 1

You can use functools.wraps :

from functools import wraps

def outer(a):
    @wraps(outer)
    def inner(x):
        return x*a
    return inner
p = outer(3)
print p  # <function outer at ...>

Answer 2

This is by no means an elegant solution, and I personally wouldn't use it. However it answers the question that you asked.

def outer(a):
    def inner(x):
        return x*a
    inner.__name__ = 'outer'
return inner

print p
<function outer at 0x10eef8e60>