Copied fromTim Visher's tools.trace documentation https://github.com/timvisher/what-does-tools-trace-do/blob/master/src/what_does_tools_trace_do/core.clj

deftrace.clj

  ;; example up from clouredocs.org:
  ;; http://clojuredocs.org/clojure_contrib/clojure.contrib.trace/deftrace
  (deftrace fib [n]
    (if (or (= n 0) (= n 1))
      1
      (+ (fib (- n 1)) (fib (- n 2)))))

  (fib 4)
  ;; => 5
  ;; 1> TRACE t2742: (fib 4)
  ;;    TRACE t2743: | (fib 3)
  ;;    TRACE t2744: | | (fib 2)
  ;;    TRACE t2745: | | | (fib 1)
  ;;    TRACE t2745: | | | => 1
  ;;    TRACE t2746: | | | (fib 0)
  ;;    TRACE t2746: | | | => 1
  ;;    TRACE t2744: | | => 2
  ;;    TRACE t2747: | | (fib 1)
  ;;    TRACE t2747: | | => 1
  ;;    TRACE t2743: | => 3
  ;;    TRACE t2748: | (fib 2)
  ;;    TRACE t2749: | | (fib 1)
  ;;    TRACE t2749: | | => 1
  ;;    TRACE t2750: | | (fib 0)
  ;;    TRACE t2750: | | => 1
  ;;    TRACE t2748: | => 2
  ;;    TRACE t2742: => 5