Transform string enum type into a union type comprising enum values

Is there a way to obtain a union type from a typescript string enum?

enum MyEnum {
  A = 'a', // The values are different from the keys, so keyof will not provide a solution.
  B = 'b',
}

When working with an enum type like the one shown above, how can one derive the union type "a" | "b" ?

Answer №1

they are both acceptable

declare function enumToUnionType<T> = T extends `${infer R}` ? R : never

declare function enumToUnionType_<T> = `${T}`

declare let x: enumToUnionType<MyEnum>
declare let y: enumToUnionType_<MyEnum>

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