Utility type to extract `Foo` from `type Bar = Set<Foo>` with just `Bar`

I am looking for a utility type that will allow me to extract the generic parameter of a set, but I only have available the typed set, so basically

type Bar = Set<Foo>;
type Baz = SomethingMagic<Bar>; // Baz should equal Foo

>Solution :

You can do that with the infer keyword:

type SomethingMagic<T> = T extends Set<infer U> ? U : never

Playground link