await (async () => {})() :: Cannot find name 'await'.ts(2304)

[teknsl]

// working
const asyncFunc = async () => {
    return someValue;
}
let someValue = await asyncFunc();

// prefered but not working
let someValue = await (async () => {
   return someValue
})();

syntactically it is correct, but still it returns error Cannot find name 'await'.ts(2304)

[marcosc90]

Note: It works perfectly fine with .js files, it's the TS compiler throwing that error.

Check: https://www.typescriptlang.org/play/?ssl=2&ssc=11&pln=2&pc=20#code/DYUwLgBAzg9gtiAagQ2AVxBAvBZB3ZAS0gApkoBPAOwGMISBKbAPggG8AoCbgJ3DR5UIAVg4BfBowDcQA

Seems to have to do with top-level await, since the following does not break (So don't know if it's a TS issue or Deno TS config)

async function get() {
  let someValue = await (async() => {
    return 5;
  })();
}

get();

[kitsonk]

I thought we had an issue for it open here, but it is an upstream TypeScript bug. Ref: microsoft/TypeScript#38483

[MarkTiedemann]

@kitsonk You mentioned this issue before in #471, which is a general issue about top-level await. Might be good to keep this one open just for this specific issue.

[jingkaimori]

this error disappear on deno 1.19.1, can this issue be closed?

[soshimee]

Not fixed on Deno 1.20.3. At least on Windows.

[kitsonk]

@soshimee can you please provide a full reproduction and the full output of deno --version.

[MarkTiedemann]

Can confirm. This never worked.

With v1.19.1:

C:\dev\test>.\deno.exe run repro.ts
error: TS2304 [ERROR]: Cannot find name 'await'.
await (async () => 1)();
~~~~~
    at file:///C:/dev/test/repro.ts:1:1

With v1.21.2:

C:\dev\test>.\deno.exe run repro.ts
Check file:///C:/dev/test/repro.ts
error: TS2311 [ERROR]: Cannot find name 'await'. Did you mean to write this in an async function?
await (async () => 1)();
~~~~~
    at file:///C:/dev/test/repro.ts:1:1

repro.ts containing await (async () => 1)();.

[soshimee]

@kitsonk

deno 1.20.3 (release, x86_64-pc-windows-msvc)
v8 10.0.139.6
typescript 4.6.2

[nhrones]

works for me

deno 1.21.2 (release, x86_64-pc-windows-msvc)
v8 10.0.139.17
typescript 4.6.2
\C:\Users\nhron> deno
Deno 1.21.2
exit using ctrl+d or close()
> await (async () => 1)();
1
>

[MierenManz]

the problem is not the code execution but the typescript error it raises when trying to typecheck the file

[nayeemrmn]

Fixed by #14875.