Comment by DylanSp

I definitely agree that ADTs are a big step forward; when I learned about them from Haskell, I was kind of baffled that they weren't more common, because the concept of "this value is always either type A or type B" is pretty simple and occurs a lot. I really wish Go had included them, because it doesn't seem like a terribly complex concept, the type switch syntax would work decently for basic pattern matching, and having ADTs built into the ecosystem from the start would be much smoother.