function bindProperty() { a = Qt.binding(function(){ return aNumber * 10 }) } function TestObject() { } TestObject.prototype.aNumber = 928349 TestObject.prototype.bindFunction = function() { return this.aNumber * 10 // this should not use the TestObject's aNumber } var testObj = new TestObject() function bindPropertyWithThis() { a = Qt.binding(testObj.bindFunction) }