[Guidance] Setting `this` in IIFE's from older JS libs

vitejs / vite

Next generation frontend tooling. It's fast!

http://vitejs.dev

MIT License

67.39k stars 6.07k forks source link

[Guidance] Setting `this` in IIFE's from older JS libs #1131

Closed arpowers closed 3 years ago

arpowers commented 3 years ago

As you may know, this is undefined in es6 modules: https://stackoverflow.com/questions/48670599/why-is-this-undefined-in-script-type-module

Because of this being undefined, there is a problem using older libs like this one: https://datamaps.github.io/ In these libs, they typically use IIFE's which assume this = window

Is there a way to patch this problem?

CHOYSEN commented 3 years ago

These libraries do not provide modular imports, so I think they should be used in the original way https://github.com/CHOYSEN/datamaps-example

arpowers commented 3 years ago

Thanks for the example, the problem with the implementation is just that the JS is loaded globally to the website. I suppose that's may be what we need to do to use this particular lib.

underfin commented 3 years ago

I only has two idea for this, that should work for you.

use extra normal scirpt link this library.
custom babel plugin transform this library to replace this inside iife.

This always is not related of vite core, so i close it for clear issue, we also can disscus it.