What are the differences between types and interfaces in TypeScript?

What are the differences between types and interfaces in TypeScript?

In TypeScript, both types and interfaces can be used to define the shape of an object, but they have some differences. Interfaces are extendable, meaning you can create new interfaces based on existing ones, while types are more flexible and can represent any valid TypeScript type, including primitives, unions, and intersections.

Can you give me an example of when to use an interface over a type?

Sure! Use an interface when you want to define a contract for classes or when you need to extend multiple interfaces. For example, if you have a base interface for a vehicle and want to create a car interface that extends it, interfaces are ideal.

What about using types for union types?

Types are perfect for union types. For instance, you can define a type that can be either a string or a number like this: type StringOrNumber = string | number;. This flexibility is one of the key advantages of using types.

Are there any performance differences between using types and interfaces?

Generally, there are no significant performance differences between types and interfaces in TypeScript. The choice between them usually comes down to design preferences and specific use cases.