What are the best practices for declaration merging in TypeScript?

What are the best practices for declaration merging in TypeScript?

Declaration merging in TypeScript allows you to combine multiple declarations into a single definition. Best practices include using interfaces for merging, keeping declarations organized, and avoiding conflicts.

Can you give an example of declaration merging?

Sure! If you have an interface User and you want to add a new property, you can declare it again:

interface User {
  name: string;
}

interface User {
  age: number;
}

This will merge both declarations into one User interface with name and age.

What should I avoid when merging declarations?

Avoid merging declarations that could lead to conflicts, such as using the same name for different types. It's also best to keep your declarations in a single file or module to maintain clarity.

Are there any tools to help with declaration merging?

Yes, tools like TypeScript's built-in compiler can help catch errors related to declaration merging. Additionally, using linters like ESLint with TypeScript plugins can help maintain best practices.