Using Caché Objects - InterSystems Documentation

The Dynamic Dispatch Methods
22.2.1 Return Values
None of the dispatch methods have specified return values. This is because each should provide
output that is of the same type of the call that originally created the need for the dispatch.
If the dispatch method cannot resolve the method or property, it can use $ZUTIL(96,3) to
throw a or error —
or whatever else may be appropriate.
22.3 The Dynamic Dispatch Methods
The following methods may be implemented to resolve unknown methods and properties:
• %DispatchMethod
• %DispatchClassMethod
• %DispatchGetProperty
• %DispatchSetProperty
• %DispatchSetMultidimProperty
• %DispatchGetModified
• %DispatchSetModified
22.3.1 %DispatchMethod
This method implements an unknown method call. Its syntax is:
Method %DispatchMethod(Method As %String, Args...)
where its first argument is the name of the referenced method and the second argument is an
array that holds all the arguments passed to the original method. Since the number of arguments
and their types can vary depending on the method being resolved, the code in
%DispatchMethod needs to handle them correctly (since the class compiler can not make
any assumptions about the type). The Args... syntax handles this flexibly.
Because %DispatchMethod attempts to resolve any unknown instance method associated
with the class, it has no specified return value; if successful, it returns a value whose type is
determined by the method being resolved and whether the caller expects a return value.
Using Caché Objects 189