Testing mutable object-oriented code tends to be a lot more tedious than testing immutable functional code. Clojure's REPL-driven development style in particula

Testing mutable object-oriented code tends to be a lot more tedious than testing immutable functional code. Clojure's REPL-driven development style in particular makes testing a breeze. Often you're just playing around with the code live and saving the results but there's also Midje for writing more formal test suites.