Uncaught SyntaxError: Unexpected Token 'Export' - How to Fix This Common JavaScript Error

Dealing with JavaScript errors can be frustrating, especially when they halt your application's functionality. One common error is the Uncaught SyntaxError: Unexpected token 'export'. In this guide, we will explore the causes of this error, how to fix it, and answer some frequently asked questions.

Table of Contents

• Understanding the Error
• Common Causes of the Error
• Solutions to Fix the Error
• Solution 1: Use the correct module syntax
• Solution 2: Use a bundler/transpiler
• Solution 3: Change the script type
• FAQs

Understanding the Error

The Uncaught SyntaxError: Unexpected token 'export' error occurs when the JavaScript interpreter encounters an export statement where it shouldn't be. The export statement is used to export functions, objects, or values from a module so that they can be used in other modules using the import statement.

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Common Causes of the Error

There are several common reasons why you might encounter this error:

1. Using the export keyword without using the correct module syntax
2. Not using a bundler or transpiler when working with ES6 modules in a browser that doesn't support them
3. Using the incorrect script tag type attribute when loading JavaScript files

Solutions to Fix the Error

Solution 1: Use the correct module syntax

Make sure you are using the correct module syntax when using the export keyword. Here's an example of the correct usage:

// module.js
export const myFunction = () => {
  console.log("Hello, World!");
};

// main.js
import { myFunction } from "./module.js";
myFunction();

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Solution 2: Use a bundler/transpiler

If you are using ES6 modules and your browser doesn't support them, consider using a bundler like Webpack or a transpiler like Babel to convert your code into a format that is compatible with older browsers.

Webpack

1. Install Webpack and the necessary loaders:

npm install webpack webpack-cli babel-loader @babel/core @babel/preset-env --save-dev

1. Create a webpack.config.js file in your project root:

const path = require("path");

module.exports = {
  entry: "./src/index.js",
  output: {
    filename: "bundle.js",
    path: path.resolve(__dirname, "dist"),
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ["@babel/preset-env"],
          },
        },
      },
    ],
  },
};

1. Update your package.json to include a build script:

"scripts": {
  "build": "webpack"
}

1. Run the build script and include the bundled output in your HTML:

npm run build

<script src="dist/bundle.js"></script>

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Babel

1. Install Babel and the necessary presets:

npm install @babel/core @babel/cli @babel/preset-env --save-dev

1. Create a .babelrc file in your project root:

{
  "presets": ["@babel/preset-env"]
}

1. Use the Babel CLI to transpile your code:

npx babel src --out-dir dist

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Solution 3: Change the script type

Ensure that you are using the correct type attribute in your script tag when loading JavaScript files that use the export keyword. The correct attribute to use is type="module".

<script type="module" src="main.js"></script>

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FAQs

1. What browsers support ES6 modules?

Modern browsers like Chrome, Firefox, Safari, and Edge support ES6 modules. However, Internet Explorer does not support them. You can find a detailed list of browser support here.

2. What is the difference between export default and named exports?

export default is used to export a single value from a module, while named exports can be used to export multiple values. When importing a default export, you can use any name you want, whereas named exports must be imported using the exact names they were exported with.

3. Can I use both named exports and default exports in the same module?

Yes, you can use both named exports and default exports in the same module. However, be aware that this can lead to confusion and is generally discouraged.

4. How do I import a specific export from a module?

You can import a specific export from a module using the following syntax:

import { myFunction } from "./module.js";

If you want to import multiple exports, you can separate them with commas:

import { myFunction, myOtherFunction } from "./module.js";

5. Can I use dynamic imports with ES6 modules?

Yes, you can use dynamic imports with ES6 modules. The import() function returns a promise that resolves to the imported module, allowing you to load modules on-demand or conditionally. Example:

if (condition) {
  import("./module.js").then((module) => {
    module.myFunction();
  });
}

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Related Links

• Introduction to JavaScript Modules
• Webpack Getting Started Guide
• Babel Usage Guide