Is a top level await equivalent possible?

[PEZ]

In the context of a Joyride script, it would be great to be able to top-level define something that needs a promise to resolve. I guess I am looking for the equivalent of:

const something = await fetchSomething();

... script continues and can use `something`

Or even just firing of something for its side effects and waiting for it:

await doThings();

... script continues when things are done

Is this even possible to get Joyride to support?

[borkdude]

@PEZ It is possible, but when we'd need to adapt the nbb way. Nbb has (nbb.core/await ...) to do such a thing.

I'm currently developing a sci.async namespace which should support this use case.

[borkdude]

we'd need to adapt the nbb way

Meaning to do everything async?

Yes. Every top level form has to be executed asynchronously. But sci.async will take care of this. The result of sci.async/eval-string* will return a promise, so that will also mean changes in joyride.

In general, a top level await should not be strictly necessary though, you can just compose foo+ functions that return promises using promesa.

[PEZ]

In general, a top level await should not be strictly necessary though, you can just compose foo+ functions that return promises using promesa.

You mean I can do this already today by instead of def using defn and to wrap the execution of the script in some kind of main function?

[borkdude]

yes. def also works, but the result is always a promise. you cannot escape that without any special means (like nbb does).

[mauricioszabo]

It is possible to have the "nbb way" that Borkdude already explained, and actually I wrote a code some time ago that patched SCI in some weird way that allowed to deref promises anywhere.

The only trouble is that it made SCI about 2x slower 🤣