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7650 :: Easiest way to pass data between threads?

• matkuki (orginal) [2021-03-17T12:37:29+01:00] view original

  Hi,

  using channels is great, but to get data from another thread by starting the transaction from the primary thread, it is necessary to signal to the the secondary thread this. Example:

  # primary module
  import os
  import secmodule
  
  var
    mythread: Thread[void]
    counter = 0
  createThread(mythread, secmodule.loop)
  
  # More code ...
  
  while true:
    counter += 1
    if counter == 10:
      counter = 0
      secmodule.send_flag = true
      let data = secmodule.chan.recv()
      echo data
    sleep(1000)
  Run

  # secondary module
  import os
  
  var
    data = "some data"
    chan*: Channel[string]
    send_flag* = false
  
  proc loop() =
    while true:
      if send_flag:
        send_flag = false
        chan.send(data)
      sleep(10)
  Run

  This works great, but is there a more direct way of getting the data variable across?

  I'm not looking for speed, convenience is more important.

  Thanks

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• mratsim (orginal) [2021-03-17T12:54:42+01:00] view original

  Channels are the best at the moment.

  In the future I think having a more convenient syntax:

  1. to create named channels
  2. to create a thread with anonymous channels to pass data to/from

  is important

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• Allin (orginal) [2021-03-17T14:03:39+01:00] view original

  You could try StashTable.

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