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How to refer overriden class functions in python

I know C++ and Java and I am unfamiliar with Pythonic programming. So maybe it is bad style what I a开发者_运维知识库m trying to do.

Consider fallowing example:

class foo:
        def a():
                __class__.b() # gives: this is foo
                bar.b() # gives: this is bar
                foo.b() # gives: this is foo
                # b() I'd like to get "this is bar" automatically

        def b():
                print("this is foo")

class bar( foo ):
        def b( ):
                print("this is bar")

bar.a()

Notice, that I am not using self parameters as I am not trying to make instances of classes, as there is no need for my task. I am just trying to refer to a function in a way that the function could be overridden.


What you want is for a to be a classmethod.

class Foo(object):
    @classmethod
    def a(cls):
        Foo.b() # gives: this is foo
        Bar.b() # gives: this is bar
        cls.b() # gives: this is bar
    @staticmethod
    def b():
        print("this is foo")

class Bar(Foo):
    @staticmethod
    def b():
        print("this is bar")

Bar.a()

I've edited your style to match the Python coding style. Use 4 spaces as your indent. Don't put extra spaces in between parenthesis. Capitalize & CamelCase class names.

A staticmethod is a method on a class that doesn't take any arguments and doesn't act on attributes of the class. A classmethod is a method on a class that gets the class automatically as an attribute.

Your use of inheritance was fine.


Quote from the Execution Model:

The scope of names defined in a class block is limited to the class block; it does not extend to the code blocks of methods – this includes generator expressions since they are implemented using a function scope.

This mean that there is no name b in the scope of function a. You should refer to it via class or instance object.

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