For convenience, I hope that the object can directly call:

function createCallableObject<T, Fn = (payload?: Partial<T>) => any>(initState: T, fn: Fn) {
  const state: any = fn;
  Object.setPrototypeOf(state, null);
  delete state.name;
  delete state.length;
  Object.assign(state, initState);
  // TODO: type
  return state as Fn & T;
}

The objects generated by createCallableObject will display some functions property i don’t want:

I have tried:

Omit<Fn, keyof Fn>

but type error: Type 'Fn' has no call signatures