I'm trying to wrap my head around types in Typescript. In general it's going well but I'm struggling to convert this function from Javascript to Typescript.

export function keyed(object, key, value) {
  const newKey = object[key];
  const newValue = object[value];
  const newObject = {};
  newObject[newKey] = newValue;
  return newObject;
};

This is my attempt so far:

type ValueOf<T> = T[keyof T];
export function keyed<T, K extends keyof T>(object: T, key: K, value: K): { [key: ValueOf<T>]: ValueOf<T> } {
  const newKey: ValueOf<T> = object[key];
  const newValue: ValueOf<T> = object[value];
  const newObject: { [key: ValueOf<T>]: ValueOf<T> } = {};
  newObject[newKey] = newValue;
  return newObject;
};

But, I'm getting a few errors like:

An index signature parameter type cannot be a literal type or generic type. Consider using a mapped object type instead.ts(1337)

and

Type 'ValueOf<T>' cannot be used to index type '{}'.ts(2536)

I've tried to use underscores DefinitelyTyped definitions to help out over here, since they do quite a bit of these operations but I haven't had any luck. Is it impossible?