Скачать или смотреть Solving the topLevelAwait Issue with babel-loader in Webpack 5

Learn how to enable top-level await functionality in Webpack 5 while using babel-loader without encountering errors.
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Understanding the topLevelAwait Issue with Babel-loader in Webpack 5

If you're building modern JavaScript applications, you might have come across the new feature called topLevelAwait. This syntax allows you to use the await keyword at the top level of your modules, making asynchronous coding more intuitive. However, when integrating topLevelAwait with babel-loader in a Webpack 5 setup, you might encounter the frustrating error:
'await' is only allowed within async functions.
So, how do you solve this issue while still using both topLevelAwait and babel-loader? Let's break it down step by step.

The Problem

With Webpack 5, enabling topLevelAwait is quite straightforward. You just need to add an option in your Webpack configuration:

[[See Video to Reveal this Text or Code Snippet]]

This allows you to use topLevelAwait seamlessly like so:

[[See Video to Reveal this Text or Code Snippet]]

However, once you introduce babel-loader with the following configuration, you run into the mentioned error:

[[See Video to Reveal this Text or Code Snippet]]

The conflicting point lies in the way babel-loader parses the code before it gets to Webpack as it doesn't recognize topLevelAwait by default.

The Solution

To resolve this issue, you'll need to enable Babel's parsing of top-level await. This step is crucial because while Webpack can manage topLevelAwait, Babel needs to be aware of it during its parsing phase. Here’s how you can do that:

Step 1: Install the Required Plugin

First, you need to install Babel's plugin that allows for parsing top-level awaits:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Update Your Babel Configuration

Once you have installed the plugin, the next step is to incorporate it into your Babel configuration. This can be done in various ways depending on your setup, but typically you'll add it to your babel-loader options in the Webpack configuration:

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Final Webpack Configuration Example

Here’s what your complete Webpack configuration might look like after implementing these changes:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By following these straightforward steps, you can successfully leverage the capabilities of topLevelAwait alongside babel-loader in your Webpack 5 setup. This allows you to write more intuitive asynchronous code without encountering the common pitfalls. Remember to always keep your tools updated to the latest versions to take full advantage of new features and improvements.

Now, get back to developing your application and enjoy the benefits of cleaner asynchronous code!