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margelo / react-native-worklets-core

🧵 A library to run JS functions ("Worklets") on separate Threads
https://margelo.io
MIT License
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Async/Await in Worklet Functions #109

Open robnewton opened 10 months ago

robnewton commented 10 months ago

Is it possible to use async/await within Worklets?

I'm trying to make calls to asynchronous functions outside of the function tagged with the worklet keyword? As a simple example, is it possible to use the Expo FileSystem async functions like copyFileAsync() from within a worklet?

When tried, I get errors like this:

TypeError: Cannot assign to read only property 'message' of object 'SyntaxError: unknown: Unexpected reserved word 'yield'.
bglgwyng commented 8 months ago

You can't do asynchronous things within worklets since they don't run the event loop as far as I know.

However, I didn't expect that async/await syntax is not supported in worklets. The error message indicates that worklets don't support generator syntax which is emitted as a transpilation result of async/await.

robnewton commented 8 months ago

That makes sense but I was hoping it would just execute synchronously. In this scenario I don't need it to be asynchronous since it's in another thread, I just need to call something which relies on that syntax.