+ * ReportBase provides a generic \ref callback::ReportBase:report method
+ * which can be used to communicate by encoding everything in its \a UserData
+ * argument.
+ *
+ * Convenient sending can be achieved by installing non-virtual methods
+ * in the TReport class, which encode the arguments in UserData and send
+ * them via ReportBase::report().
+ *
+ * Convenient receiving can be achieved by installing virtual methods in
+ * the TReport class, which can be simply overloaded by the receiver. Downside
+ * of this is that adding virtual methods breaks binary compatibility.