[sc34wg3] TM Data Model issue: assoc-role-player-type

[Geir Ove Grønmo]

* Geir Ove Grønmo
| * Kal Ahmed
| | I think it makes more sense to require the [role playing topic] property
| | to be non-null. 
| | 
| | If you want to say that  the player is unknown, then you should be
| | required to create a topic to represent the "unknown" entity. After all,
| | if you say that the role player is unknown, then you are saying that
| | there is a subject that is the role player in the association (topic
| | maps don't allow fuzzy statements) and it is clear that the one thing
| | known about the role playing subject is that it plays a role in an
| | association. 
| 
| I like this solution: mandatory role types and "blank" topics for
| "missing" role player references.
| 
| This should cover both the mandatory [type] and [role playing topic]
| properties view and the current optional content model of association
| roles in XTM.

Oh, except for the optional role type [in XTM] that is.

Geir O.