Enable async/await to work on functions that don't just return promises.

[Michał Wadas]

Actually, this proposal would be a revolution and I can think of too
many edge cases to make it viable.

Consider:

async function foo() {

    async function bar() {

        [1,2,3].forEach(async function() {                 async return
3;      });

    } return (await bar()) + 39;

}

What does happen here? For me it's absolutely counterintuitive.
What about functions coming from other scopes, like?

async function foo() {

    function bar() {

        [1,2,3].forEach(async function() {                 async return
3;      });

    } return (await bar()) + 39;

}

Or multiple returns?


async function foo() {

    setTimeout(()=>{ async return 42; }, 0); return null;

}


Promisification should be done by userland libraries, not by introducing
new syntax.



On 27/02/17 22:17, Isiah Meadows wrote:
> I was speaking objectively about the proposal itself, and the scope of
> it. I'm personally strongly against it for reasons I stated earlier in
> the thread (the status quo is better IMHO). I was just trying to
> direct people back to the actual scope of the proposal instead of
> basically reinventing async functions using async functions, and also
> simultaneously attempting to assist the OP in better understanding
> what he's really trying to propose (which he didn't appear to grasp
> well). 
>
> On Mon, Feb 27, 2017, 14:01 Tab Atkins Jr. <jackalmage at gmail.com
> <mailto:jackalmage at gmail.com>> wrote:
>
>     On Mon, Feb 27, 2017 at 12:41 AM, Isiah Meadows
>     <isiahmeadows at gmail.com <mailto:isiahmeadows at gmail.com>> wrote:
>     > May I add one more thing: the main topic this was about is adapting
>     > non-standard async APIs (like Node's error-first callback idiom)
>     to the land
>     > of promises. Async functions and iterators are incredibly useful
>     when you're
>     > dealing with just promises, especially consuming them, but this
>     is about
>     > creating promise adapters, not consuming promises.
>
>     You don't need to change the behavior of core syntax to make
>     Node-style error-first callbacks work.  That's easily done by
>     libraries, which have existed in Node-land for quite a while, and can
>     automatically convert functions that take Node-style callbacks into
>     functions that return promises.
>
>     ~TJ
>
>
>
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