Es6 modules in the browser: Uncaught SyntaxError: Unexpected token import

Detailed walkthrough: Troubleshooting import error

Don't go into battle unprepared. Arm yourself with these coding Excaliburs to conquer the error dragon 🗡️.

Initialization: Checking browser compatibility

Lo and behold, modern browsers now support ES6 modules. However, for the time travelers out there stuck in the IE6 dimension—use tools like caniuse.com to gauge compatibility. If stuck, remember Babel and Webpack are your Delorean and flux capacitor for time travel—they can transport ES6 modules back to ES5 age.

Eliminating Syntax Errors: The correct import syntax

A marching import syntax command should march like this:

//Troops! Import all superheroes from './avengers.js'
import { CaptainAmerica, IronMan, Thor } from './avengers.js'; 
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Feeling adventurous? Rope in the whole squad like this:

// All in! Avengers, assemble! 
import * as Avengers from './avengers.js'; 
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Serving correctly: Exporting from modules

Enable sharing by shouting export out loud from your module files, sort of like announcing a party invitation to neighborhood:

// 📣 Attention everyone, myFunction is ready to party!
export function myFunction() {...};
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And when the party of the century is going down, default exports are your BFF:

// 🎉 The event of the year, every year... MyClass!
export default class MyClass {...};
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Visualise: How to. Implement ES6 modules

Visualisation is a Star Trek holodeck for coders, transforming abstract concept into tangible codes that make sense.

Organising HTML: Structure with care

Build a steep pyramid of <script type="module"> tags, each marking the presence of a majestic module:

<!-- Here King Tut lies (in JS code) -->
<script type="module" src="/path/to/KingTut.js"></script>
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Ensuring Readability: UTF-8 charset

To avoid the script talking in alien tongue, make sure your HTML hails in UTF-8 charset:

<!-- Speaking Human -->
<meta charset="UTF-8">
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Scheduling Execution: Defer

Use defer when you want your scripts to be the punctuation, not the sentence. In other words, they execute after the HTML is evaluated:

<!-- Patience is a virtue, defer to this wise old saying -->
<script type="module" src="/path/to/ScriptGuru.js" defer></script>
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Error handling: Understanding Unexpected token import error

Fear not the ominous sounding "Uncaught SyntaxError: Unexpected token import". It's the browser’s way of saying type="module" missing or server misconfiguration.

Strip out ambiguities: URLs in imports

Clear up any doubts with specific URLs in your import statements:

// No twists and turns, straight route only
import { myFunction } from '/modules/myModule.js';
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Learning from the masters: Using Practical Examples

For an illuminating lantern in the foggy path of ES6, check out Paul Irish's ToDo MVC. His examples decode ES6 module usage like a pro.