Import vs Require #

This page is intended for those who are unfamiliar with the import statement or may have assumed it's only relevant to TypeScript. While import is not specific to JellyCommands or discord.js, understanding how to use it is a fundamental skill in JavaScript development. Whether you're new to the language or just need a refresher, this page is designed to help you improve your JavaScript knowledge and skills.

What is import and export syntax #

If you're new to the Discord bot space and JavaScript development in general, you might be more familiar with the require statement from the old Node.js module syntax (CJS), which uses module.exports. However, in modern JavaScript development, it's recommended to use the new JavaScript module syntax (ESM), which uses import and export. This syntax is not only cleaner but also more powerful, making it an ideal choice for transitioning to in your development work. By using ESM syntax, you can take advantage of modern JavaScript features and improve the readability and maintainability of your code.

ESM Support #

ESM is supported in Node.js versions 12 and above. However, both discord.js and JellyCommands require Node.js 16 or higher, so you won't encounter any issues when using ESM syntax in these libraries. We recommend using the latest LTS (Long-term Support) version of Node.js, which provides stability and security updates over an extended period of time.

To use ESM syntax in your project, you may need to add a configuration field to your package.json file. Simply add the following line:

"type": "module",

Importing Modules #

In JavaScript, you can use external code from other files and libraries by importing it into your code. There are two ways to import code, using the require syntax in CommonJS (CJS) or the import syntax in ECMAScript Modules (ESM).

Importing with require in CommonJS #

In CommonJS, you use the require method to import a module. When you use require to import a module, you assign the imported code to a variable. For example, to import the Client class from the discord.js library:

const { Client } = require('discord.js');

In this example, we are using object destructuring to extract the Client class from the discord.js library.

Importing with import in ESM #

In ESM, you use the import keyword to import a module. The import keyword is followed by a pair of curly braces {} when importing named exports, or it can be used alone when importing default exports. Here's how to import the same Client class from discord.js using import:

import { Client } from 'discord.js';

Default Imports in CommonJS and ESM #

In CommonJS, you can use require to import a default export from a module. The default export is assigned to the variable specified in the require statement. For example:

const Discord = require('discord.js');

In this example, Discord is the default export of the discord.js module.

In ESM, you can use the import keyword followed by the variable name to import the default export of a module. For example:

import Discord from 'discord.js';

In this example, Discord is the default export of the discord.js module.

Exporting Modules #

To make code available for importing, modules need to use module.exports or export statements to define what code can be used outside of the module.

Named Exports #

In CommonJS, you can export named exports by assigning them to properties of the module.exports object. For example:

module.exports.something = 'Hello World';

In this example, we are exporting an object with a property called something that has a value of 'Hello World'.

In ESM, you use the export keyword to export named exports. For example:

export const something = 'Hello World';

In this example, we are exporting a constant called something that has a value of 'Hello World'.

Default Exports #

In CommonJS, you can export a default export by assigning it to module.exports. For example:

module.exports = 'Hello World';

In this example, we are exporting a string that says 'Hello World'.

In ESM, you use export default to export a default export. For example:

export default 'Hello World';

In this example, we are exporting a string that says 'Hello World'.

Using Named and Default Exports #

In CommonJS, you can only export one value per module, either as a named export or a default export. In ESM, you can have both named and default exports in the same module.

For example, in a single ESM module you can have a default export:

export default 'Hello World';

and also named exports:

export const something = true;

To import both named and default exports from the same ESM module, you can use the following syntax:

import helloWorld, { something } from './test.js';

In this example, we are importing both the default export helloWorld and the named export something from the test.js module.

You can also import them separately:

import helloWorld from './test.js';
import { something } from './test.js';

This way you can use the named exports and default exports in different parts of your code.

Support #

If you're having trouble adapting to the new module system, feel free to join our Discord server for assistance. Both the CommonJS (CJS) and ECMAScript Modules (ESM) are supported by JellyCommands and discord.js, so you can switch between them if needed.