Yes, Clojure 1.4 defaults to static. However, a Var still needs to do an extra lookup at runtime. A Var does not directly point to the object that I want. And Vars have to be that way, this is their core feature. Clojure is a dynamic language, so they need to stay dynamic too.

All code constantly assumes that the objects behind Vars will change. Let’s say we have `(defn foo [] 1)`. The caller of (foo) will first lookup the address in RAM of the compiled function, and then jump to it. Because of this dynamicy we can redefine foo at runtime: `(defn foo [] 2)`. All callers still function, and will now get the result `2`. In statically compiled languages this would not happen, because `foo` is translated to the direct address of the first function. The concept of replacing functions at runtime doesn’t exist in that way.

But I would like to see an optional “static” programming feature: I want to be able to mark functions as final. This would be nice after major development has happened. A function object that Clojure created could then not be changed any longer, without restarting the JVM. But such functions can be called directly, without any overhead.