What are the differences between TypeScript and JavaScript interfaces?

What are the differences between TypeScript and JavaScript interfaces?

TypeScript interfaces are a way to define the structure of an object, while JavaScript does not have a built-in interface concept. TypeScript's interfaces provide type-checking at compile time, which helps catch errors early.

Can you give me an example of how to use an interface in TypeScript?

Sure! Here's a simple example:

interface User {
    name: string;
    age: number;
}

const user: User = {
    name: 'Alice',
    age: 30
};

This defines a User interface with name and age properties.

What about JavaScript? How do I achieve similar functionality?

In JavaScript, you can use objects to achieve similar functionality, but without the type-checking. For example:

const user = {
    name: 'Alice',
    age: 30
};

However, you won't have the compile-time checks that TypeScript provides.

Are there any performance differences between using TypeScript and JavaScript?

TypeScript compiles to JavaScript, so the performance at runtime is similar. However, TypeScript can help improve development speed and reduce bugs, which can lead to better performance in the long run.