I ran into higher rank lifetimes while trying to use a library in my program. You can totally pass closures around in a dynamic language like JavaScript without

I ran into higher rank lifetimes while trying to use a library in my program. You can totally pass closures around in a dynamic language like JavaScript without any issues (you just pay for it in performance). In Rust `-> impl Trait` is a new feature so it's still not at all polished. I would argue that Rust has a higher learning curve overall than any dynamic language because of its type system.