CommonJS vs ES6 Modules

What are the main differences between CommonJS and ES6 modules?

CommonJS is a module system used in Node.js, while ES6 modules are part of the ECMAScript 2015 standard. CommonJS uses require() to import modules and module.exports to export them, whereas ES6 uses import and export syntax. Additionally, ES6 modules are statically analyzed, allowing for better optimization.

Can you give me an example of how to use both in a project?

Sure! In CommonJS, you might have a file called math.js with module.exports = { add: (a, b) => a + b };. In another file, you would use const math = require('./math');. For ES6, you would write export const add = (a, b) => a + b; in math.js, and import it with import { add } from './math.js';.

Which one should I use for a new project?

If you're working on a Node.js project, CommonJS is still widely used, but ES6 modules are becoming the standard, especially for front-end development. If your environment supports ES6, it's recommended to use it for better compatibility with modern tools.

Are there any performance differences between the two?

Yes, ES6 modules can be more performant due to their static structure, which allows for better tree-shaking and optimization by bundlers. CommonJS modules are loaded at runtime, which can lead to slower performance in some cases.