@async function must return something?

[andyli]

Tested with Haxe 3.4.7 and tink_await 0.4.0.

Compile:

@await class Test {
    @async static function main() {
        return;
    }
}

Results in:

?:1: characters 1-7 : The macro didn't return a valid result

The error can be avoided by replacing return; with return null;. I guess it makes sense for tink_await to do the return; -> return null; transformation automatically.

[kevinresol]

Try

@await class Main {
    @await static function main() {
        if(@await foo() == 1) return;
        trace(2);
    }

    @async static function foo() return 1;

    static function check() {
        $type(main); // Void -> Void
        $type(foo); // Void -> tink.core.Promise<Int>
    }
}

There is a difference for @async and @await when used to annotate a function.

@async expects a return value and the function will be transformed into returning a Promise<T> @await doesn't expect a return value and its return type will be Void

[kevinresol]

And currently there is no check to enforce @async actually returns something for all the possible branches. But that is https://github.com/haxetink/tink_await/issues/6.

[andyli]

Ah, I see. Is the @async @await difference documented somewhere?

[kevinresol]

oops, looks like no. But there is an open issue for that https://github.com/haxetink/tink_await/issues/16

[andyli]

I guess copying your comment above into the README would be good enough.

[kevinresol]

Done, a bit rough but should be fine for now.

[sonygod]

Done !

use return null instead of return.