Menu
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?
527
The self keyword is used to represent an instance (object) of the given class. In this case, the two Cat objects cat1 and cat2 have their own name and age attributes. If there was no self argument, the same class couldn't hold the information for both these objects.
self vs clsThe difference between the keywords self and cls reside only in the method type. If the created method is an instance method then the reserved word self has to be used, but if the method is a class method then the keyword cls must be used.
The self is used to represent the instance of the class. With this keyword, you can access the attributes and methods of the class in python. It binds the attributes with the given arguments. The reason why we use self is that Python does not use the '@' syntax to refer to instance attributes.
return self would return the object that the method was called from.
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
72
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
