JavaScript: Cannot Use Import Statement Outside a Module

The “Cannot Use Import Statement Outside a Module” error is a common roadblock for JavaScript developers, especially those transitioning to ES6 module syntax.

This error can be puzzling, but fear not – in this comprehensive guide, we’ll demystify the issue and provide you with a step-by-step solution to resolve it in your JavaScript projects.

Understanding the Error

The “Cannot Use Import Statement Outside a Module” error occurs in JavaScript when you attempt to use ES6 module syntax (import and export) without configuring JavaScript to recognize it.

This issue arises because JavaScript treats the code as CommonJS modules by default.

When and Why Does This Error Occur?

This error typically occurs when:

• You’re using ES6 module syntax in a JavaScript project.
• JavaScript is not configured to handle ES6 modules.

Common Causes

Before we dive into the solution, let’s examine some common reasons behind the “Cannot Use Import Statement Outside a Module” error in JavaScript:

Incorrect File Extensions

Using the wrong file extension in your import statements can trigger this error. Ensure that your imported JavaScript files have the .mjs extension.

Missing "type" Declaration

To use ES6 modules in a JavaScript project, you need to declare the module type in your HTML file by adding the type="module" attribute to your <script> tags.

Without this declaration, JavaScript defaults to CommonJS modules, leading to the error.

Improper JavaScript Configuration

In some cases, an improper JavaScript configuration can result in this error.

It’s essential to ensure that your project’s settings align with your requirements.

Solution: Configure JavaScript for ES6 Modules

To resolve the “Cannot Use Import Statement Outside a Module” error in JavaScript, follow these steps:

1. Create an HTML File:

– Create a new HTML file for your project or open an existing one.

2. Use the type="module" Attribute:

– In your HTML file, add the type="module" attribute to your <script> tags.

This tells the browser to treat the included JavaScript files as ES6 modules.

3. Save the Changes:

– Save your HTML file.

By configuring JavaScript to use ES6 modules with the type="module" attribute, you enable the use of import and export statements without encountering the error.

Example Code

Here’s an example illustrating how to configure JavaScript for ES6 modules in your HTML file: