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2950 :: newbie: simulating setTimeout

• mashingan (orginal) [2017-05-09T01:49:24+02:00] view original

  I'm trying to simulate setTimeout with spawn but apparently it cannot work properly

  import threadpool
  from os import sleep
  
  type
    TimerObj[T] = object
      doit: bool
      time: int
      when T isnot void:
        arg: T
        exec: ExecProc[T]
      else:
        exec: ExecNoArg
    
    ExecNoArg = proc()
    
    Timer[T] = ref TimerObj[T]
    PTimer[T] = ptr TimerObj[T]
  
  proc runit(x: PTimer[void], duration: int) =
    sleep duration
    if x.doit:
      x.exec()
  
  proc setTimeout(exec: ExecNoArg, duration: int): Timer[void] =
    var temp: Timer[void]
    new temp
    temp.exec = exec
    temp.doit = true
    temp.time = duration
    
    spawn runit(temp[].addr, duration)
    
    result = temp
  
  proc cancelTimeout[T](timer: var Timer[T]) =
    timer.doit = false
  
  var timer = setTimeout(
    (proc() = echo "interweaving echo"),
    300)
  
  cancelTimeout timer # should set the branch false and won't run the supply proc
  
  sleep 400           # if it works, it'll silently end
  Run

  How to make it works correctly?

  Also, if any, please tell me a better approach for this.

  Thanks in advance.

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