Enumeration the properties of a qbs object in Product{}

Product {
   ...
   Depends { name: "cpp" }
   ...

    property var testEnumeration: {
        print("+++ testEnumeration ++++");

        print("product");
        print(this);
        for (var p in this) {
           print(p);
        }
        print("");

        print("project");
        print(project);
        for (var p in project) {
           // Here never we get...
           print(p);
        }
        print("");

        print("cpp");
        print(cpp);
        for (var i in cpp) {
           // Here never we get...
           print(i);
        }
        print("");

        print("+++ testEnumeration +++");
    }

}