Suggestion: Constructor<T> and Class<T>

[na-sa-do]

type Constructor<T> = new(...x: any[]) => T;

type Class<T> = Constructor<T> & {
    prototype: T;
}

The use case for these should be fairly obvious. I'm separating them because, according to MDN, a constructor could choose to return an object that doesn't actually have the constructor's .prototype as its prototype -- but this doesn't actually work in Chrome for me; is that a bug in Chrome or an inaccuracy in MDN? I can't follow the spec well enough to tell either way.

It's worth noting that Constructor<T> should be revised if #5453 or #12265 get added, to the effect of

type Constructor<T, ...U> = {
    new(...U): T;
}

type Class<T, ...U> = Constructor<T, ...U> & {
    prototype: T;
}

but backwards compatibility there requires type argument defaults (I swear I've seen a proposal for that, but I can't find it, or I'd link it too); maybe it would be better to prefix these versions with Vague or something to that effect?

[mhegazy]

We limit the number of additional declarations added to the library to avoid namespace pollution, and to limit back-compat liabilities. You are welcome to define these type aliases as noted above in your own project and leverage them as needed.

[typescript-bot]

Automatically closing this issue for housekeeping purposes. The issue labels indicate that it is unactionable at the moment or has already been addressed.