> Templates are the main means of constraint on archetypes - Specialisations > are mainly > about adding attributes.
Sam, surely those attributes are available by virtue of the fact that the parent archetype says nothing about them. Something in an archetype can never 'add' an attribute. All archetypes can do is constrain. And the specialised archetype can never remove a constraint of the parent surely? For example, an observation archetype that says nothing about the 'State' attribute imposes no constraints on that attribute. A specialisation of the archetype could impose extra constraints on 'State', but can't add the attribute in. I mean, there is either a 'state' attribute there in the RM or not - the archetype can't add attributes. Of course this all leads to a much more interesting theoretical question - aside from the immediate syntactic differences, what exactly is the difference between a template and a specialisation? Andrew
