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Re: Augment data models posted



So you need a construct that is something like:
   noderel="(subnode|iref)"    (01)

Eugene Eric Kim wrote:    (02)

> On Mon, 17 Sep 2001, Eric Armstrong wrote:
>
> > Resending to the list instead of Eugene, at Eugene's
> > request, so the question can be archived.
>
> Thanks, Eric.
>
> > > 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).
>
> 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.
>
> 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.
>
> -Eugene
>
> --
> +=== 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  ===========+    (03)