Ideas that the modeling are thinking about and discussing
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The new collection structure has a container (Collection) and members (Member). In order to allow for nested collections without resorting to multiple inheritance, we have to make Member a subclass of Collection. That has implications in cases like Node and NodeSet, since it will make Node a Collection too. We need to discuss this. The To address the issue, there is a constraint defined on the subclass relationship between Member and Collection: If isCollection = true then Member is a subclass of Collection, otherwise it is not. The default is false. The following diagram illustrates the model:
Modelling correspondences/maps (added by Flavio)
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