Native ECMAScript modules: nomodule attribute for the migration

In one of my previous articles Native ECMAScript modules: the new features and differences from Webpack modules we attempted to detect if the browser supported ES modules. We needed this to determine either, to execute a bundled (classic) file or a script which uses the native ECMAScript module features.

We managed to achieve this, but in reality how it was achieved isn’t ideal. The community have since come together to propose an alternative, the nomodule script attribute.

...

Native ECMAScript modules: dynamic import()

In the previous article Native ECMAScript modules: the new features and differences from Webpack modules we understood the differences between ES modules and their implementation in bundlers/compilers like Webpack/Babel. So far we found couple gotchas and know how to use the import \ export declarations and which caveats we may have using them in JS.

But JavaScript went asynchronous many years ago, and it is a good practice is to use non-blocking Promise-based syntax for modern Web applications. ECMAScript modules are static by default: you have to define static import/exports on the top level of the module. It is very helpful to apply JS engine optimizations but doesn’t allow developers to apply the best practices of asynchronous module loading.

Meet the dynamic import() operator, which adds the missed functionality and follows the best practices of Promise-based API.

...

Web Share API brings the native sharing capabilities to the browser

For many years the Web is moving towards the parity with the Mobile native applications and adds the missed features. Today browsers have most of them, from the offline mode and enhancements with the Service Workers to Geolocation and NFC.

The one huge ability, which is still missed, but highly used in the mobile applications- the ability to share a page, article or some specific data.

The Web Share API is the first step to fill the gap and bring the native sharing capabilities to the Web.

...

Native ECMAScript modules: the new features and differences from Webpack modules

In the previous article Native ECMAScript modules - the first overview I described the history of the JavaScript modules and the current situation with the native ECMAScript modules implementation:

For now, we have 2 available implementations, which we tried and compared to the bundled module.

The main takeaways, so far, are:

  1. To execute a script or load an external file and execute it as a module use <script type="module">
  2. .js extension cannot be omitted in the import (the exact URL should be provided)
  3. the modules’ scope is not global and this doesn’t refer to anything
  4. native modules are in the strict mode by default (not needed to provide 'use strict' anymore)
  5. module scripts are deferred by default (like <script type="text/javascript" defer />)

In this article, we are going to understand other differences with the bundled modules, abilities to interact with the module scripts, how to rewrite Webpack modules to native ES ones and other tips and tricks.

...