What are the differences between Haskell type classes and interfaces?

What are the differences between Haskell type classes and interfaces?

Haskell type classes are a way to define a set of functions that can operate on different types, while interfaces in languages like Java define a contract that classes must follow. Type classes allow for ad-hoc polymorphism, whereas interfaces provide a more rigid structure.

Can you give an example of a type class in Haskell?

Sure! A common example is the Eq type class, which defines the == and /= functions for checking equality. Any type that implements Eq can be compared for equality.

How do interfaces in Java compare to type classes in terms of flexibility?

Type classes offer more flexibility because they allow you to define functions that can work with any type that implements the class, without needing to modify the type itself. In contrast, Java interfaces require explicit implementation in the class.

Are there any performance differences between using type classes and interfaces?

Performance can vary based on the implementation. Type classes can introduce some overhead due to dictionary passing, while interfaces may have a slight overhead due to dynamic dispatch. However, the differences are often negligible in practice.