TypeScript: cannot find name async/await

Question

I'm using typescript@next and I want to compile my code to es5, but each time I'm using async or await keywords the compiler errors with that message:

Cannot find name 'await'.

Heres my libs: dom, es2015, es2016, es2017.

Code example:

let asyncFn = () => {
   return new Promise((resolve:Function)=>{resolve(2)})
}
// should log `2`
console.log(await asyncFn())

Such things are possible even with [email protected], I've tried it, but somehow I am unable to compile my code anyway.

Please post your code. Is your function marked with async? — Stephen Cleary
– Stephen Cleary, Commented Nov 3, 2016 at 13:18
no, it's not, but I don't need to mark my scope as 'async', right? afaik that's only syntastic sugar for Promise — roomcayz
– roomcayz, Commented Nov 3, 2016 at 13:42
Read the documentation: "Asynchronous functions are prefixed with the async keyword" — user47589
– user47589, Commented Nov 3, 2016 at 13:45
@Roomy: async and await are a pair of keywords. You can't use await unless it's within an async scope. — Stephen Cleary
– Stephen Cleary, Commented Nov 3, 2016 at 15:35

Nico · Accepted Answer · 2016-12-15 21:40:40Z

35

You need to use your asyncFn inside a function marked as an 'async' function. For example:

async someAsyncCode() {
    let asyncFn = () => {
        return new Promise((resolve: Function) => { resolve(2); });
    }
    // should log `2`
    console.log(await asyncFn());
}

answered Dec 15, 2016 at 21:40

Nico

1,21215 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

user9993 Over a year ago

Pretty shocking that even the dumb TypeScript compiler can't give a better error message. Something like await cannot be used outside of an async scope would have been fine.

Collectives™ on Stack Overflow

TypeScript: cannot find name async/await

1 Answer 1

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related