Obtaining references to function objects on the ex

2019-06-06 22:42发布

问题:

Given the output of inspect.stack(), is it possible to get the function objects from anywhere from the stack frame and call these? If so, how?

(I already know how to get the names of the functions.)

Here is what I'm getting at: Let's say I'm a function and I'm trying to determine if my caller is a generator or a regular function? I need to call inspect.isgeneratorfunction() on the function object. And how do you figure out who called you? inspect.stack(), right? So if I can somehow put those together, I'll have the answer to my question. Perhaps there is an easier way to do this?

回答1:

Here is a code snippet that do it. There is no error checking. The idea is to find in the locals of the grand parent the function object that was called. The function object returned should be the parent. If you want to also search the builtins, then simply look into stacks[2][0].f_builtins.

def f():
    stacks  = inspect.stack()
    grand_parent_locals = stacks[2][0].f_locals
    caller_name = stacks[1][3]
    candidate = grand_parent_locals[caller_name]

In the case of a class, one can write the following (inspired by Marcin solution)

class test(object):
    def f(self):
        stack = inspect.stack()
        parent_func_name = stack[1][3]
        parent_func = getattr(self, parent_func_name).im_func


回答2:

I took the following approach, very similar to Eolmar's answer.

stack = inspect.stack()
parent_locals = stack[1][0].f_locals['self']
parent_func_name = stack[1][3]
parent_func_attr = getattr(parent_locals,parent_func_name)
parent_func = parent_func_attr.im_func
is_parent_gen = inspect.isgeneratorfunction(func)