ref: 3ff4453f5f5898a7b44d47218945d4385c2f5c32
dir: /lib/thread/util.myr/
use std
use thread
pkg thrtestutil =
const mkherd : (n : uint32, fn : (-> void) ->void)
;;
const mkherd = {n, fn
for var i = 0; i < n; i++
std.try(thread.spawn(fn))
;;
}