[bstamour]

Why have functions and control structures when we can just jmp?

[geezerjay]

That's a disingenuous comparison. Functions are used pervasively, but even the visitor pattern isn't used very often.

[bstamour]

But in languages that support multiple dispatch at the language level, they're just another way of writing polymorphic functions. They're not just a niche feature. When you don't have to write all of the ceremony of the visitor pattern, it's easier to use visitors everywhere without thinking about them.