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.
:::tip TLDR
Use ESM import syntax, not require
. Project’s generated with npm create jellycommands
support it out of the box! Continue reading if you are unsure what this means.
:::
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 18 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:
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:
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
:
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:
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:
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:
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:
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:
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:
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:
and also named exports:
To import both named and default exports from the same ESM module, you can use the following syntax:
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:
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.