Top level await breaks on parentheses

[rsp]

This is fine:

const x = await 1;

This is not:

const x = await (1 + 2);

It exits with: error TS2304: Cannot find name 'await'.

$ deno -v
deno: 0.24.0
v8: 8.0.192
typescript: 3.7.2

The above is the most minimal example that shows this.

More realistic use case - if I have a promise p like this:

const p = Promise.resolve({ x: Promise.resolve(1) });

I cannot get to the value 1 in one step:

const val = await (await p).x;

It exits with: error TS2304: Cannot find name 'await'.

I have to do it in two steps:

const tmp = (await p).x;
const val = await tmp;

I suppose that those are the parentheses (maybe the compiler thinks it is a function call?) but I can be wrong here.

[kevinkassimo]

This seems to be TS only. JS works fine

Looks like we have to wait for TypeScript 3.8 to get full support from TS on TLA

[kitsonk]

Agreed, we can't just safely ignore TS2304 as it might ignore other things incorrectly, and adding logic to introspect the error message would be a bit of a slippery slope for something we are already hacking around.

[ry]

We just have to wait for TS to fix it.

[rsp]

For reference:

• Top level await breaks with parentheses microsoft/TypeScript#35276
• Top Level Await microsoft/TypeScript#25988