Python Classes vs. Rust Traits: A Comparison of Object-Oriented Programming Features
Tags: python, rust, oop
Published: 2023-12-08 04:53:51

There are some of the differences and similarities between Python classes and Rust traits/implementations. I think I need more practice on some serious projects to make more informed conclusions, so this is just how I understand the topic at the moment.

## Differences

The same logic in Python and Rust can look very different due to the different approach to implementing object-oriented programming ideas in their languages.

- Python classes are types that can be instantiated to create objects, while Rust traits are not types but rather collections of methods that can be implemented by any type. Rust implementations are blocks of code that provide the concrete behavior of a trait for a specific type.
- Python classes support inheritance, which means a class can inherit the attributes and methods of another class and modify or extend them. Rust traits do not support inheritance, but they can be composed of other traits. Rust implementations can also use the super keyword to access the methods of a parent trait.
- Python classes support multiple inheritance, which means a class can inherit from more than one class at the same time. Rust traits do not support multiple inheritance, but a type can implement multiple traits and a trait can require multiple traits as bounds. Rust also has a feature called trait objects, which allow a type to be dynamically dispatched to any trait that it implements.
- Python classes support metaclasses, which are classes that define the behavior of other classes. Metaclasses can be used to customize the creation and modification of classes at runtime, and implement advanced features such as descriptors, decorators, and abstract base classes. Rust traits do not have an equivalent feature, but they can use macros to generate code or implement generic behavior.
- Python classes use the self keyword to refer to the current instance of the class within a method, while Rust traits use the self, &self, or &mut self parameters to refer to the current instance of the type that implements the trait. Rust also has a feature called associated types, which allow a trait to define a type that is associated with the implementing type.

## Similarities

Python classes and Rust traits/implementations are both ways to define and implement object-oriented programming concepts in their respective languages. They have some common features, such as:

- They both support [polymorphism](https://dev.to/antonov_mike/polymorphism-in-rust-and-python-simple-examples-29co), which means you can write generic code that can work with different types of objects without knowing their exact implementation.
- They both support [abstraction](https://dev.to/antonov_mike/abstraction-in-rust-and-python-simple-examples-5dd8), which means you can hide the internal details of a class or a trait and expose only the relevant information and functionality to the outside world.
- They both support [encapsulation](https://dev.to/antonov_mike/how-rust-and-python-implement-encapsulation-4ick), which means you can control the access to the attributes and methods of a class or a trait using public, private, and protected modifiers.
- They both support [composition](https://dev.to/antonov_mike/composition-in-rust-and-python-21c3), which means you can combine the features of different classes or traits to create more complex and powerful classes or types.

## Conclusion

To sum up, I tried to compare and contrast Python classes and Rust traits/implementations as ways to implement object-oriented programming concepts. While they share some common features, such as polymorphism, abstraction, encapsulation, and composition, they also differ in many aspects, such as inheritance, metaclasses, trait objects, and associated types. These differences stem from the different philosophies and paradigms of each language, and they have implications for the performance, safety, and expressiveness of the code.
No one is worst, no one is better but both can be interesting in their own way.

Image created by Bing and edited by me

P.S.:
An addition to this article: [Python classes vs Rust structures](https://dev.to/antonov_mike/python-classes-vs-rust-structures-nod)