Array element label as string in type

Can an array type element’s label be accessed as string?

I have a labeled array type, and want to create an object type, with the labels as properties:

type A = [a: number, b: string];
type Transform<T> = /* ... */;
type B = Transform<A>; // { a: number, b: string }

The application is having a function, and assuring a data-structure has the same properties as there are arguments:

const data: Transform<Parameters<typeof f>>[] = [];
function f(a: number, b: string) { data.push({ a, b }); }

The trivial alternative is writing out the type manually, but such repetition is to be avoided, if possible.

>Solution :

No, this is not possible.

There is no syntax in Typescript that can resolve tuple labels in any useful way. They propagate through to your IDE for informational purposes, but that’s the end of it.

You also can’t go the other way. You cannot create labels dynamically from string types. There’s just no syntax for that.

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