ios - Using GCD in Swift CLI -


so i'm trying use gcd in cli. test out wrote code this:

import foundation  var = 0  print("a: ",i)  dispatch_async(dispatch_get_global_queue(qos_class_user_initiated, 0)) {      n in 1..<10{         i++     }      print("c: ",i)      dispatch_async(dispatch_get_main_queue()){         print("d: ",i)     } }  print("b: ",i)  sleep(5) print("e: ",i)

the output of is: a: 0 b: 0 c: 9 e: 9

with last line printing few seconds later. i'm trying find out happened @ d? nothing put in block seems execute. works fine when use in ios, not in cli.

the cli lacks persistence of app. came end (terminated) before d had chance printed.

as @user3441734 rightly points out, can work around in cli calling dispatch_main() last thing before exit. call forces dip main queue right now , pull out main-queued block , execute it, before exiting.


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