... but with that being said, 3.7 seems to have broken many aspects of the `Promise.all` interface. Right now the largest issue seems to be that if any `Promise` result in `Promise.all` is nullable, all of the results are nullable.
The result should instead be a tuple, but IDK how well tuple size inference would work in a case like that.
type Tuple<T, K> = [T, K | null];
...JavaScript would allow you to extend that list during runtime (unless you freeze it)
type Tuple<T, K> = [T, K]
const Tuple<T, K> = (x: T, y: K): Tuple<T, K> => {
const tup = [x, y];
Object.freeze(tup);
return tup;
};It is a well hidden secret, and one that I'm not going to try to lookup the docs for on mobile, but the idea is that the operator strips null/undefined from the type of whatever is before it.
So you can do something like this:
const [ a, b ] = await Promise.all([
async () => ({ foo: 'bar' }),
() => null
])
console.log(a!.foo) // `a!` strips the nullable off `a`I thought you had to actually provide a Promise to `Promise.all`, not functions that return promises (you have to invoke the functions):
const [ a, b ] = await Promise.all([
(async () => ({ foo: 'bar' }))(),
(() => null)(),
])