Let’s say I have an interface such as:

interface DataShapes {
  shape1: { a: number };
  shape2: { b: string };
}

Is it possible to define a type ToUnion such that ToUnion<DataShapes> produces a discriminated union like:

 | { key: 'shape1', value: { a: number } }
 | { key: 'shape2', value: { b: string } }