What does 'self' refer to in a @classmethod?

python self class-method
Yes - that Jake. picture Yes - that Jake. · Feb 10, 2009 · Viewed 13.2k times · Source

I thought I was starting to get a grip on "the Python way" of programming. Methods of a class accept self as the first parameter to refer to the instance of the class whose context the method is being called in. The @classmethod decorator refers to a method whose functionality is associated with the class, but which doesn't reference a specific instance.

So, what does the first parameter of a @classmethod (canonically 'self') refer to if the method is meant to be called without an instance reference?

Answer

SilentGhost picture SilentGhost · Feb 10, 2009

class itself:

A class method receives the class as implicit first argument, just like an instance method receives the instance.

class C:
    @classmethod
    def f(cls):
        print(cls.__name__, type(cls))

>>> C.f()
C <class 'type'>

and it's cls canonically, btw

Related questions

What __init__ and self do in Python?

I'm learning the Python programming language and I've came across something I don't fully understand. In a method like: def method(self, blah): def __init__(?): .... .... What does self do? What is it meant to be? Is it mandatory? What does …

Read More
What is the purpose of the word 'self'?

What is the purpose of the self word in Python? I understand it refers to the specific object created from that class, but I can't see why it explicitly needs to be added to every function as a parameter. To …

Read More
TypeError: method() takes 1 positional argument but 2 were given

If I have a class... class MyClass: def method(arg): print(arg) ...which I use to create an object... my_object = MyClass() ...on which I call method("foo") like so... >>> my_object.method("foo") Traceback (most recent …

Read More