Allow explicit upcast of abstract outgoing references

Description

In existing metamodels refrences often reference abstract classes. However in most cases the concrete subtype of the referenced class of interest is known when the query is written.

Example: The Reference "members.MemberContainer.members" of the class "Interface" is of abstract type "Member", however links only to members that are of type "InterfaceMethod". It would be desirable to write:

Environment

None
Fixed

Assignee

Oliver Schneider

Reporter

Oliver Schneider

Labels

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Requirement Category

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External issue URL

None

Priority

Minor