I find two typo on this page : http://qt-project.org/doc/qt-5.0/qtcore/properties.html
A REVISION number is optional. If included, it defines the the property and its notifier signal to be used in a particular revision of the API that is exposed to QML.
Suppose we have a class MyClass, which is derived from QObject and which uses the Q_OBJECT macro in its private section. We want to declare a property in MyClass to keep track of a priorty value. The name of the property will be priority, and its type will be an enumeration type named Priority, which is defined in MyClass.