MOF26 — Migration of package relationships

Summary:
At MOF 1.4, packages can be related through:

• import
• nesting
• inheritance
• clustering
  We haven't really addressed this aspect of migration which should be added to Chapter 9.
  Personally I think there's little value in MOF 1.4 nesting and inheritance relationships and they're infrequently used in real metamodels (if people know what they're doing - occasionally people nest packages in UML Profile for MOF without realizing the implications).

In UML2 though we do still have a nesting relationship between packages so should consider the implications in terms of MOF constraints and extents.

Conversely we no longer have clustering (the most useful relationship in MOF 1.4) though we do have merging (with 2 flavors): we need to consider the runtime implications of instantiating a package that merges other packages. Is it the same as clustering?