What are the practical differences between interfaces and types in TypeScript?

What are the practical differences between interfaces and types in TypeScript?

In TypeScript, both interfaces and types can be used to define the shape of an object, but they have some differences. Interfaces are extendable and can be merged, while types are more flexible and can represent any valid TypeScript type.

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 class that implements an interface, it ensures that the class adheres to the defined structure.

What about using types for union types?

Great point! Types are perfect for creating union types. For instance, you can define a type that can be either a string or a number, which is something interfaces cannot do.

Are there any performance differences between using interfaces and types?

Generally, there are no significant performance differences in TypeScript. The choice between interfaces and types is more about design and use cases rather than performance.