SYSML2 — Causation end features need to redefine source and target

The connection definition Causation in the CausationConnections library package has two ends that redefine the non-end features causes and effects from Multicausation.

However, in the normative CausationConnections.sysml file from the Cause and Effect Domain Library project, these ends are declared to only subset the source and target ends inherited from BinaryConnection. As a result, the connection definition ends up having four ends rather than two, which is incorrect. Its ends need to redefine source and target, rather than just subsetting them.

In subclause 9.5.2.2.1 of the specification document, on the other hand, Causation is not shown as specializing BinaryConnection at all, and the ends are shown as only redefining the non-end features from Multicausation.