FUML — Items excluded from Kernel

Specification: Semantics of a Foundational Subset for Executable UML Models (ptc/2008-11-03)
Subclause: 7.2.2 Kernel

There are some things excluded from the Kernel in the fUML subset that would probably be better to include.

• ElementImport and PackageImport: While these are irrelevant to execution, they will often be used in models with elements that are otherwise executable. It seems unnecessary to force these to be stripped out in order to not have the model rejected by an execution tool.

• Class::nestedClassifier: It is sometimes useful to nest one classifier in another, and this would have no effect on the execution semantics. So it also seems unnecessary to force a model to be re-organized to remove such nesting just in order to not have the model rejected by an execution tool.

• Package::ownedType and Package::nestedPackage: These derived properties are not needed for fUML, but they really should be included in the fUML subset in order to make it a well formed subset of UML L3 and to ensure that constraints in the UML spec involving these properties an be carried over without change into fUML.

Agreed.