function 
    /usr/local/lib/janet/spork/tasker.janet  on  line  245 , column  1 
    (run-executors  tasker  &opt  workers-per-queue  pre-task  post-task )
    Start  a  number  of  executors  to  run  tasks  as  with  
    `tasker/spawn-executors` , and  then  wait  for  all  executors  to  
    complete.