How do you get a union of an object's values as a type?

Question presented to candidate: "You have a constant object mapping names to status strings. How do you get a type that is the union of its values, so a function only accepts those strings? Walk me through why each part is needed."

What a strong answer should cover:

• The pattern (typeof Obj)[keyof typeof Obj]: typeof turns the value into a type, keyof gives its keys, and indexing with the whole key union gives the union of values
• as const is required: without it the values widen to string and the "union" is just string
• A reusable type ValueOf<T> = T[keyof T]; arrays use [number] instead ((typeof arr)[number])
• The run-time side: the type is erased, so validating input needs Object.values(Obj) plus a type guard (and a widening cast for includes)
• Pitfalls: ValueOf on an array or tuple also picks up length and method types; it is one level deep, so nested objects need a recursive helper
• Trade-offs versus enum; as const satisfies Record<string, number> to check the shape while keeping literals

Code / implementation expected: Yes — derive the union from a constant object and use it as a parameter type.