Expo Web failed to compile "optional chaining"

Question

Looks like Expo Webpack doesn't optional chaining.

I found this when I tried to install UI Kitten to Expo Web app.

This is the compile error after I added UI Kitten to the newly created Expo app

node_modules/@ui-kitten/components/ui/input/input.component.js 104:38
Module parse failed: Unexpected token (104:38)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
|         this.webEventResponder = devsupport_1.WebEventResponder.create(this);
|         this.focus = () => {
>             this.textInputRef.current?.focus();
|         };
|         this.blur = () => {

Deps versions(latest ones at the moment that I'm writing here.)

• [email protected]
• @ui-kitten/[email protected]

Any tips to hack around this?

Answer 1

Webpack uses Acorn parser, and Acorn does not support optional chaining as of now.

There is a pending pull request which you can subscribe to to get notified about the progress.

So your workaround options are:

• do not use webpack
• do not use optional chaining
• integrate Babel into your stack, and make sure to pass all *.js-files through Babel first, using this Babel plugin
• wait for the aforementioned PR to be merged and the next version including this PR to be released
• fork Acorn, merge the PR yourself, then fork webpack and make it use your forked Acorn

Answer 2

As @connexo says, the workaround is to integrate a babel plugin. Also, this issue has already been discussed on the github.