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Re: Augment data models posted

On Mon, 17 Sep 2001, Eric Armstrong wrote:    (01)

> Resending to the list instead of Eugene, at Eugene's
> request, so the question can be archived.    (02)

Thanks, Eric.    (03)

> > On Mon, 17 Sep 2001, Eric Armstrong wrote:
> >
> > > In answer to the original question:
> > >   Is there any way to define link types??
> > >   That's needed, to distinguish pure hierarchy (subnode)
> > > from transclusions and cyclic links (iref).    (04)

In a sense, noderel does define link types.  In the Groves world, there
are only three: subnode, iref, and uref.  Additionally, as far as I can
tell, it imposes the link type on all nodes in a property.  This is the
problem.  If I could define noderel to be both subnode and iref (and
perhaps even uref), then this would take care of the transclusions issue.    (05)

Note that Lee gets around this problem by avoiding it altogether. :-)
There are no link types, or relationship constraints, in the NODAL data
modeling language.    (06)

-Eugene    (07)

+=== Eugene Eric Kim ===== eekim@eekim.com ===== http://www.eekim.com/ ===+
|       "Writer's block is a fancy term made up by whiners so they        |
+=====  can have an excuse to drink alcohol."  --Steve Martin  ===========+    (08)