Generics allow us to create components that can operate over a variety of types rather than a single one. This flexibility means that users can consume these components and use their own types. For instance, in TypeScript, instead of giving a function a specific type, we can use generics to capture the type of the argument, ensuring that the same type is used for both input and output.
Without generics, we might resort to using the any type, which accepts all types. However, this approach loses the type information, making our code less safe. Generics, on the other hand, let us capture and retain this type information.
Once we've defined a generic function, we can call it in multiple ways:
Sometimes, we might want our generic function to work with types that have certain properties. For instance, if we want to ensure that a type has a .length property, we can define a constraint:
Generics aren't limited to functions. We can also use them in classes:
Generics in TypeScript provide a robust way to create reusable and adaptable components. By understanding and leveraging generics, developers can write safer and more flexible code, ensuring that their applications are both robust and maintainable.