Alias.qml
Qt Code: 
  1. import QtQuick 2.0
  2.  
  3. Rectangle {
  4.     width: 100
  5.     height: 62
  6.  
  7.     property var arr : [1,2,3,4]
  8. }
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Access.qml

Qt Code: 
  1. import QtQuick 2.0
  2.  
  3. Rectangle {
  4.     id: newq
  5.  
  6.     width: 100
  7.     height: 62
  8.  
  9.     property var yy : [1]
  10.     property var pp : [1]
  11.  
  12.     onPpChanged:
  13.     {
  14.         console.log("\npp: " +  pp.pop())
  15.         console.log("\nyy: " + newq.yy.length + "\n")
  16.     }
  17. }
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main.qml
Qt Code: 
  1. import QtQuick 2.0
  2.  
  3. Rectangle {
  4.     id: root
  5.     width: 360
  6.     height: 360
  7.  
  8.     Alias
  9.     {
  10.         id: poi
  11.     }
  12.  
  13.     Access
  14.     {
  15.         pp: poi.arr
  16.     }
  17. }
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The error shows up on this line:
Qt Code: 
  1. console.log("\nyy: " + newq.yy.length + "\n")
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Where am I going wrong?