fiber_vs_function_call.janet

(defmacro timeit2
  ```
  Time the execution of `form` using `os/clock` before and after,
  and print the result to stdout.  returns: result of executing `form`.
  Uses `tag` (default "Elapsed time:") to tag the printout.
  ```
  [form &opt tag]
  (default tag "Elapsed time:")
  (with-syms [start result end]
    ~(do
       (def ,start (os/clock))
       (def ,result ,form)
       (def ,end (os/clock))
       (- ,end ,start))))


(def wat (fiber/new (fn [] (while true (yield 1)))))
(def wat2 (fn [] 1))

(do
  (var res 0)
  (loop [i :range [0 100000]]
    (+= res (timeit2 (resume wat))))
  res)
#=> 0.277963

(do
  (var res 0)
  (loop [i :range [0 100000]]
    (+= res (timeit2 (wat2))))
  res)
#=> 0.276217