Are modules serializable?

[sancarn]

I am very excited about this idea, as it finally gives us syntax sugar for a scopeless blocks! Are modules serializable?

Scenarios like node's @jxa library should be considered in this scenario. JXA has global Application and $ objects which already pose typescript issues ofc, but more to the point it's difficult to see from libraries such as @jxa, that variables won't be in scope. E.G

import { run } from "@jxa/run";
let someVar = 1
export const currentUserName = () => {
    // This callback function is run as JXA
    return run(() => {
        return someVar;
    });
};
currentUserName() //returns undefined

At least with modules it will be very clear that this is a new and seperate scope.

export const currentUserName = new JXAFunction(
    module {
        const sys = Application("System Events");
        return sys.currentUser().name();
    }
)
currentUserName() //returns <current user name>

Features like this will only be doable if module are serializable, however.

[littledan]

Sorry, what do you mean by serializable exactly? Module blocks support .toString() and postMessage.

[sancarn]

I guess in an ideal world it'd be nice if you could just obtain the body of the code block. But even getting module {...} via toString() would be sufficient.

[Jack-Works]

I guess the answer is yes, it may pass the structured clone algorithms but that algorithm is not defined in the JS.

[Jamesernator]

Just as a note, the code provided:

export const currentUserName = new JXAFunction(
    module {
        const sys = Application("System Events");
        return sys.currentUser().name();
    }
)
currentUserName() //returns <current user name>

Won't work because the code inside module { still needs to be a syntatically valid module, and as return is not allowed in the top level of a module, this will be a SyntaxError.

You can just export a function though, and import and call that function instead:

module {
    export default function() {
        const sys = Application("System Events");
        return sys.currentUser().name();
    }
}