4Geeks logo
4Geeks logo

Bootcamps

Explore our extensive collection of courses designed to help you master various subjects and skills. Whether you're a beginner or an advanced learner, there's something here for everyone.

Academy

Learn live

Join us for our free workshops, webinars, and other events to learn more about our programs and get started on your journey to becoming a developer.

Upcoming live events

Learning library

For all the self-taught geeks out there, here is our content library with most of the learning materials we have produced throughout the years.

It makes sense to start learning by reading and watching videos about fundamentals and how things work.

Full-Stack Software Developer - 16w

Data Science and Machine Learning - 16 wks

Search from all Lessons


LoginGet Started
← Back to Lessons

Weekly Coding Challenge

Every week, we pick a real-life project to build your portfolio and get ready for a job. All projects are built with ChatGPT as co-pilot!

Start the Challenge

Podcast: Code Sets You Free

A tech-culture podcast where you learn to fight the enemies that blocks your way to become a successful professional in tech.

Listen the podcast
Edit on Github

JavaScript Import and Export of Modules

This is how "import" and "export" work:
Exporting by default

☝️ This lesson is for users of WebPack and ECMAScript Modules (ESM) syntax. There is another way to work with modules using the CommonJS syntax that we will not cover.

All of our JS code cannot be on the same file; that will make it hard to read and almost impossible to maintain.

Thanks to Webpack, we can split our code into small files however we want, and then we are able to reference other files from our current one.

We have actually been doing that already when we import our styles, bootstrap, or jQuery from the index.html.

This is how "import" and "export" work:

  • You use the word import to bring variables, classes, or functions from other files.
  • You use the word export to export variables, classes or functions to be used by other files.

For example, here we are importing a function from another file:

javascript import

javascript import

Exporting by default

There is one small variation that you can find over the internet that is called "export default" – this is just a way of exporting one thing by default onto your file.

You can only export ONE variable by default, and you don’t have to use the curly brackets while importing.

Importing the default

1// Content on index.js 2 3import multiplyFunction from './my_file.js'; 4 5let total = multiplyFunction(3,6) 6console.log(total);

Exporting by default

1// Content on my_file.js 2 3let multiplyFunction = function(a,b) { 4 return a*b; 5}; 6 7export default multiplyFunction;

Final Example:

Here is a small demonstration of all the import/export types working on the same project.