Class Decorators

Classes are also objects in Python (frankly, pretty much everything is an object in Python, and it's hard to find a counter-example; however, there are some technical nuances). That means the same considerations apply; they can also be passed by parameters, assigned to variables, asked some methods, or be transformed (decorated).

The difference between class and function decorators

Class decorators were introduced in PEP-3129, and they have very similar considerations to the function decorators we just explored. The only difference is that when writing the code for this kind of decorator, we have to take into consideration that we are receiving a class as a parameter of the wrapped method, not another function.

Writing class decorators

We saw how to use a class decorator when we saw the dataclasses.dataclass decorator in an earlier lesson (Creating Classes with a More Compact Syntax). Now, we'll learn how to write our own class decorators.

Some practitioners might argue that decorating a class is something rather convoluted and that such a scenario might jeopardize readability because we would be declaring some attributes and methods in the class. But behind the scenes, the decorator might be applying changes that would render a completely different class.

This assessment is true, but only if this technique is heavily abused. Objectively, this is no different from decorating functions; after all, classes are just another type of object in the Python ecosystem, as functions are.