Constrainedby clause not verified by the NF

[Francesco Casella]

Consider the attached test package. The Component model is invalid, because it calls function fa which is contained in the default AdvancedMedium package, but is not defined in the constraining class BaseMedium. Unfortunately, Component is checked successfully.

This is too bad, because SystemBroken should be fine, according to the constraining class clause. In fact, it is broken because Component is not valid in the first place.

The NF should eventually check that the models are valid under the constraining class clause, and report an error if they aren't.