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Comment by jmull | Hacker News Reader

> To see that for yourself, try to re-write our async code snippet again using only async/await statements and see how does that pan out.

With async/await, wouldn't the example just be:

    let aOut = doA();
    let bOut = doB();
    let cOut = doC(aOut);
    doD(bOut);
    doE(cOut, aOut, bOut);

That is, it looks the same as the sync version.

The difference is in the "do" functions themselves: they would be async (meaning they return a promise, and they accept promises as parameters).

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so in your code sample, would 'aOut' be a promise or a value? in case it is a promise, then basically doC() would needed to be re-written to handle when it gets a promised value instead of an actual value, and if not, then doA() must be invoked synchronously, i.e. the `let bOut = doB()` statement must be awaiting `let aOut = doA()` statement which is not what the desired async execution flow is.

Yes, aOut would be a promise. It would look like this:

    async function doA() {
        ...
        return "the-result-of-a";
    }

(Which returns a promise. Assuming execution reaches that last line of my sample code, the promise will resolve to "the-result-of-a" when you "await" it.)

> ...then basically doC() would needed to be re-written to handle when it gets a promised value instead of an actual value

Well, wait a minute... it wasn't written in the first place! Let's write it though. It would look like this:

   async function doC( param ) {
       ...
       // we use "await param" where we want to
       // access the value of param. e.g.:
       const paramValue = await param;

       ...
    }

So not bad.

yeah really not bad at all, didn't think of that solution originally. edited the article accordingly.

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