[ebingdom]

> static typing is less expressive than dynamic typing

Here's something I can express with static typing that I can't express with dynamic typing: "this function returns a function which returns an integer for every input". There's no test you could write to verify this property. So I'm inclined to say that static typing is more expressive, since it gives me a way to express and verify properties like this.

[blain_the_train]

clojure spec will do this in the way you're asking.