proc_type - Processing type

The processing type for a function or expression defines the way the function is processed. Aggregation functions or other functions, which process a whole collection, must be marked as collection methods. By default, methods are considered to be instance methods, i.e. methods, which require a selected instance for running. The processing type is ignored for static methods, which do not work on a calling collection or instance.

Some (mainly system functions) are marked as status functions, which return a state about the passed property handle.