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Python Object-Oriented Python (retired) Inheritance Subclasses

Posted by Sergio Lopez
Sergio Lopez
13,088 Points

What's the difference between subclasses and instances of a class?

They seem to be as similar as to be the same thing. Just curious.

2 Answers

Kenneth Love
STAFF
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher 
class Shape:
    sides = 0

class Square(Shape):
    sides = 4

diamond = Square()
diamond.rotate = 90

Square is a subclass of Shape. diamond is an instance of Square.

Tristan Gaebler
Tristan Gaebler
6,204 Points

Kenneth Love . How do they actually differ? Don't they have the same attributes?

Zachary Smith
Zachary Smith
1,592 Points
Zachary Smith
Zachary Smith
1,592 Points

So in this case, Square would be given all the attributes a shape has with the exception that 'sides' is initialized to a difference number. If there was another attribute under the Square class, say 'length', then it would have all the attributes Shape has (that it inherited from) plus it's new attribute 'length'. Diamond on the other hand is an instance of Square. So it is given all the attributes of the Square class ('sides' and 'length').