How can I use TypeScript with CommonJS modules?

How can I use TypeScript with CommonJS modules?

You can use TypeScript with CommonJS by setting the module option in your tsconfig.json to 'commonjs'. This allows TypeScript to compile your code into CommonJS format.

What do I need to install to get started?

You'll need to install TypeScript itself, which you can do via npm with the command npm install typescript --save-dev. Additionally, if you're using Node.js, ensure you have it installed.

Can you show me a simple example?

Sure! Here's a simple example:

// math.ts
export function add(a: number, b: number): number {
    return a + b;
}

// app.ts
import { add } from './math';
console.log(add(2, 3));

Compile it with tsc and run the output JavaScript file with Node.js.

What if I want to use ES6 modules instead?

If you want to use ES6 modules, you can set the module option in your tsconfig.json to 'es6' or 'esnext'. Just remember to use the import and export syntax.