typed-null-prototype.ts

type Value = string | number;
type Indexable<V> = { [key: string]: V };

function makeTypedNullPrototype<T = any, V = Value>(obj: T): T & Indexable<V> {
    return Object.setPrototypeOf(obj, null);
}

// const p = makeTypedNullPrototype({
//     a: 3
// });

// console.log(
//     p[prompt()!]
// );