async/await loop await

Question

I want to test use loop to await.

// works fine
async function asyncFunc() {
    let arr = ['a', 'b', 'c'];

    for (let i = 0; i < arr.length; i++) {
        console.log(await arr[i]);
    }
}

asyncFunc()

async function asyncFunc() {
    let arr = ['a', 'b', 'c'];

    arr.forEach(function(el) {    // get an error:  SyntaxError: missing ) after argument list
        console.log(await el);
    })
}

asyncFunc()

async function asyncFunc() {
    let arr = ['a', 'b', 'c'];

    arr.forEach((el) => {        // get an error here:  SyntaxError: missing ) after argument list
        console.log(await el);
    })
}

asyncFunc()

Can someone tell me what's wrong here?

editor: VS code
node: 8.0.0

I know that i can't use await out of the current async function context.

So i am sure i will get an error on the second one.

But i do not know why i also get an error on the third one. Does the arrow function and the async function have the different context ???

I'm pretty sure you're getting the error on the line below your comment, right? — Bergi, Jul 16 '17 at 13:57
You're trying to use `await` in a function that is not an `async` function (the `forEach()` callback function). — Pointy, Jul 16 '17 at 13:57
In what environment are you getting that error message? It's not super helpful - it should rather say that the `await` keyword cannot be used there. — Bergi, Jul 16 '17 at 13:58
@Bergi isn't `await` parsed as a plain identifier in contexts where it can't be used? Or maybe I'm thinking of something else. — Pointy, Jul 16 '17 at 14:01
@Pointy Yes, that's what happens here - it expects either `console.log(await)` or `console.log(await, el)` or something, so that's why it's complaining about a missing parenthesis. Which is what I'd call "not helpful" — Bergi, Jul 16 '17 at 14:02
@Bergi I update the question just now, could you take a glance? thank u — percy507, Jul 16 '17 at 14:50
Yes, it does not matter whether it's an arrow function or a function expression or any other function syntax, they're two different functions. — Bergi, Jul 16 '17 at 20:54

async/await loop await

0 Answers0