QML's list ought to support JavaScript's for(var i in list) syntax

import QtQuick 2.0
Rectangle {
    width: 400; height: 600
    Column {
        anchors.centerIn: parent
        spacing: 3
        Repeater {
            model: 3
            delegate: Rectangle {
                width: 50; height: 50; color: "blue"
            }
        }

        Component.onCompleted: {
            for(var i = 0; i < children.length; i++) {       // works
                print("child: " + children[i].toString());
            }

//            for(var i in children) {                       // doesn't work
//                print("child: " + children[i].toString());
//            }
        }
    }
}