-
-
Save justinribeiro/676b3ed3526553bfb1b67e149bceca63 to your computer and use it in GitHub Desktop.
Feature detect ES modules: both static import and dynamic import()
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <!-- | |
| Complete feature detection for ES modules. Covers: | |
| 1. Static import: import * from './foo.js'; | |
| 2. Dynamic import(): import('./foo.js').then(module => {...}); | |
| Demo: http://jsbin.com/tilisaledu/1/edit?html,output | |
| Thanks to @_gsathya, @kevincennis, @rauschma, @malyw for the help. | |
| --> | |
| <body></body> | |
| <!-- Remember: static modules have a fallback! --> | |
| <script type="module"> | |
| console.log('This browser supports <script type="module">'); | |
| </script> | |
| <script nomodule> | |
| console.log('This browser DOES NOT support <script type="module">'); | |
| </script> | |
| <script> | |
| // Feature detect static imports. | |
| function supportsStaticImport() { | |
| const script = document.createElement('script'); | |
| return 'noModule' in script; | |
| } | |
| // Feature detect dynamic import(). | |
| function supportsDynamicImport() { | |
| try { | |
| new Function('import("")'); | |
| return true; | |
| } catch (err) { | |
| return false; | |
| } | |
| } | |
| // Usage. | |
| let el = document.createElement('pre'); | |
| el.textContent = ` | |
| Supports ES module static import: ${supportsStaticImport()} | |
| Supports dynamic ES module import(): ${supportsDynamicImport()} | |
| ` | |
| document.body.appendChild(el); | |
| </script> |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment