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2243 :: add a block to template..

• sam (orginal) [2016-05-02T15:41:14+02:00] view original

  below is a template for gtk3's signal connect

  template connect(w: Widget, cmd: expr, p: stmt) =
      discard w.gSignalConnect(cmd, cast[Gcallback](proc() = p), nil)
  Run

  a problem here: the variable val is not local

  button.connect "clicked":
      let val = 10
      echo "hello", val
      echo "b2 clicked"
  
  echo "val = ", val
  # if button clicked => output val = 10
  # else              => output val = 0
  Run

  add a block here, but ugly:

  b2.connect "clicked":
      block:
          let val = 10
          echo "hello", val
          echo "b2 clicked"
  Run

  How to add a block to that template?

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• OderWat (orginal) [2016-05-02T16:09:35+02:00] view original

  Does this help?

  template connect(obj: RootObj, cmd: expr, p: expr) =
    block: p
  
  let a = RootObj()
  
  a.connect "clicked":
    let val = 10
    echo "hello", val
    echo "b2 clicked"
  
  #echo "val = ", val # undefined
  Run

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