Here is some code: class Person def initialize(age) @age = age end def age @age end def age_difference_with(other_person) (self.age – other_person.age).abs end protected :age end What I want to know is the difference between using @age and self.age in age_difference_with method. 6 Answers 6
When defining a method on a class in Python, it looks something like this: class MyClass(object): def __init__(self, x, y): self.x = x self.y = y But in some other languages, such as C#, you have a reference to the object that the method is bound to with the “this” keyword without declaring it as … Read more
Why is cls sometimes used instead of self as an argument in Python classes? For example: class Person: def __init__(self, firstname, lastname): self.firstname = firstname self.lastname = lastname @classmethod def from_fullname(cls, fullname): cls.firstname, cls.lastname = fullname.split(‘ ‘, 1) 6 Answers 6
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 call last): File “<stdin>”, line 1, in <module> TypeError: method() takes exactly 1 positional argument (2 given) …why does Python tell me I … Read more
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 the __init__ method do? Why is it necessary? (etc.) I think they might be … Read more
What is the purpose of the self word in Python? I understand it refers to the specific object instance created from that class. But why does it explicitly need to be added to every function as a parameter? To illustrate, in Ruby I can do this: class MyClass def func(name) @name = name end end … Read more
