Question

i have this code:

def some_method():
    #i need to get some attrs :(
    return 'blabla'

setattr(parent, 'new_attr', some_method)

it’s there a way to get other attributes of the parent inside the some_method function?

Thanks in advance!

Update: (solution)

I solved in this way, i don’t know if the best.

def some_method(parent):
    # print or do something parent.xy_attribute
    return 'blabla'

parent.new_attr = some_method(parent)

and it works!

Thanks again!

Answer 1

If parent were a class, then you can access its attributes like you would with any other method of a class, by giving the self parameter and using that.

If it isn’t a class, perhaps the best way to handle this would be to write your function within a wrapper/factory/something instead of as a method directly.

def some_method_wrapper(parent):

    def some_method():
        #access any parent attribute 
        #by using the parent positional argument passed to the function
        print parent.desired_attribute
        return 'blabla'

    setattr(parent, 'new_attr', some_method)

You can then use parent.new_attr() and it’ll be able to print/manipulate/whatever any parent attributes you want.

Here’s a more fleshed out example of how you might use this to manipulate a counter on a function (or, say, flush a function cache).

def parent_function(numbers):
    # do something with numbers
    parent_function.counter += 1
    return sum(numbers)

parent_function.counter = 0

def add_reset_function(parent):

    def reset_counter():
        parent.counter = 0

    setattr(parent, 'reset', reset_counter)

# call parent_function a few times

numbers = [1, 2, 3]
for i in range(4): parent_function(numbers)
print parent_function.counter # 4

add_reset_function(parent_function)

# call the reset function just added
parent_function.reset()

print parent_function.counter # 0
parent_function(numbers)
print parent_function.counter # 1