(function measure
  (let [start result end] [(time) (... . args) (time)])
  (str result " took " (- end start) "ms"))

(function fib n
  (if (< n 2) n
      (+ (fib (dec n))
         (fib (- n 2)))))

(measure fib 35)
;returns "9227465 took 26497ms"