async job example

[larshp]

Hi,
I tried adding the async example as a test case, see https://github.com/larshp/microjob/commit/5dd6c7b5bdf6110c59fe88cf476b15583906877e

It gives Error: __awaiter is not defined, am I doing something wrong, missing any black magic?

[wilk]

Good catch!
I think this bug has been introduced during the TS refactoring.

[wilk]

This problem is related to TS: the worker thread is run-time JS and it gets some JS-compiled from TS.
However, when you compile an async function via TS, you'll get the __awaiter wrapper that's not defined inside the worker thread.
I'm trying to figure out how to pass all the compiled TS and not just a little part of it.

[wilk]

After further investigation, I think I need to rewrite microjob back to JS, leaving just the typings definition.
Unfortunately, the function in charge of wrapping the async job is created at run-time and this does not fit with TS compilation.
As explained here: https://basarat.gitbooks.io/typescript/docs/async-await.html the compilation of async functions is done through generators and that just does not work with native await keyword.
Having a mix of run-time JS and compiled TS is basically bad.

[ddwwcruz]

Not really? __awaiter is made because TS attempts to make async/await usable by versions of node that don't have it. In my experience setting target to es2017 works for this sort of thing.

[ddwwcruz]

Also this package requires an experimental part of node anyway. We might as well compile TS to the latest version of JS.

[wilk]

@ddwwcruz great suggestion!
Fixed in version v0.3.1 (just shipped) 🎉