Beginner's question on tutorial

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   Hi,

probably dump beginner's queststion. Still here they come:

1) Evaluation Tutorial

It concerns the definition of the family binding: we explicitely added to Parent-Roles to the binding expressing that a Family-Relationship needs exactely 2 Parents. Then we specified that it may have [0,N] Child-Roles.

Why didn't we add only 1 Parent-Role specifying [2,2] cardinality.

Isn't that the same thing?

2) Graphical Modeling

Is Inheritance a language construct of its own? Could it not have been expressed as a Relationship with Supertype- and Subtype-Roles respectively?

Sorry if these are dump, but thanx for any response.

best regards

volker

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vkoster Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 17.Jul.2009 Location: Bochum, Germany Points: 2	Post Options Post Reply Quote vkoster Report Post Thanks(0) Quote Reply Topic: Beginner's question on tutorial Posted: 17.Jul.2009 at 13:47
	Hi, probably dump beginner's queststion. Still here they come: 1) Evaluation Tutorial It concerns the definition of the family binding: we explicitely added to Parent-Roles to the binding expressing that a Family-Relationship needs exactely 2 Parents. Then we specified that it may have [0,N] Child-Roles. Why didn't we add only 1 Parent-Role specifying [2,2] cardinality. Isn't that the same thing? 2) Graphical Modeling Is Inheritance a language construct of its own? Could it not have been expressed as a Relationship with Supertype- and Subtype-Roles respectively? Sorry if these are dump, but thanx for any response. best regards volker

janne Members Profile Send Private Message Find Members Posts Add to Buddy List MetaCase Joined: 25.Mar.2008 Points: 58	Post Options Post Reply Quote janne Report Post Thanks(0) Quote Reply Posted: 17.Jul.2009 at 14:33
	Hi Volker, 1) Yes, you are right, both ways in the binding defintion can be used. 2) Yes, it could have been done like you described. Inheritance as an own concept was implemented to simplify the graphical metamodeling language: Now Inheritance can have an own notation in the model and it could also have own "Inheritance specific" constraints. Also the binding definitions are little bit simpler. There are also some changes needed for the MXM generators, if an approach with generic relationship and Supertype- and Subtype-roles would have been chosen.

vkoster Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 17.Jul.2009 Location: Bochum, Germany Points: 2	Post Options Post Reply Quote vkoster Report Post Thanks(0) Quote Reply Posted: 17.Jul.2009 at 15:10
	Thanx! That puts me at ease :-) have a nice weekend volker