Comment by rahulmutt

I should mention that a good testing discipline is required in Eta as well but you would focus your testing on high-level properties using frameworks like QuickCheck. Moreover, you don't lose as much if you don't write tests like you would in dynamic languages like Clojure.

Thanks for the example! My point was not that you can't test effectively in Clojure, but just that doing things like refactoring is much easier in Eta because of the numerous static checks.