[gherkinnn]

The MDN Docs never disappoint[0]. Even more details can be gotten from the author of OP's link: Exploring JS[1]. And if you're wondering why the catch block isn't typed properly in Typescript, see this [2] thread.

0 - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

1 - https://exploringjs.com/es6/ch_async.html

2 - https://github.com/microsoft/TypeScript/issues/6283#issuecom...