Proposal for #399

[skinkie]

In order to futher the restrict the schema to sensible values and relations I would like to introduce two things:

1. Have an explicit default for non-generic nameOfRefClass attributes, in the case below, ScheduledStopPointRef has a natural nameOfRefClass being ScheduledSopPoint. Now a parser does not have to guess what the default might be. And this could also help with schematron validation, since conditional key-identity-constraints are still far away.
2. Further we would like to have a sane list of Elements that might be referenced. From my perspective this should include all objects up to some predefined point. I think that should be something like "every parent, excluding abstract parents, up to and not included DataManagedObject". I would like to prevent siblings to be included.

[ue71603]

@skinkie does this not result in automatic cycles in the necesseray import of elements?

[skinkie]

@skinkie does this not result in automatic cycles in the necesseray import of elements?

Not really, because the base element is a "xs:string" hence, is a pure text description, not limited to the actual elements defined.

[ue71603]

Ok, I see it is only the text "TimingPoint"