[tmql-wg] Every thing is a 'thing'
Lars Marius Garshol
larsga at garshol.priv.no
Fri Mar 9 06:59:17 EST 2007
* Robert Barta
> Right. Or we could take the viewpoint that
> $thing isa tm:topic
> gives all topics and
The trouble with this one is that if we return the "drrho" topic here
we claim that you are a topic, but as far as I know you're actually
*not* part of any topic map, but rather a living, breathing person.
So that would be semantically wrong. :-/
> $thing isa tm:subject
> gives (2) or (3) above. Question is whether values are 'subjects' in
> the TMDM sense.
The easiest type of question on earth is questions of the form
"Is X a 'subject' in the Topic Maps sense?"
The answer is always the same: yes. (Just read the definition.)
Values are subjects, you are a subject, the question of whether
values are subjects is a subject, the bottle of beer next to my
laptop is a subject, Topic Maps is a subject, ... "Any thing
>>> ? Should all map items be an instance of tm:subject implicitly
>>> + tm:subject is a great placeholder
>>> - TMDM does not say it (or does it?)
>> Whooops. Does this mean that you intend for it to be (2)?
> I'm just asking. If atomic values _are_ subjects, then it would be
> (2), right? And if not, then probably (3), I guess.
You mean the other way around, right?
Anyway, the question here isn't just what the semantics are, but also
what we *want*. And I think we want something that produces all
> The question is what should
> (a) select $x where $x isa tm:subject
I think I prefer (1), which was "all topics", on the grounds that
- "isa" is an association, and associations only apply to topics,
- the set of all topics is what we want, anyway.
> (b) select $x where $x iko tm:subject
This is the subclasses of tm:subject, right? In that case it should
be all topic types. (Although it *could* be all types.)
> I think we shortly touched this one in Leipzig, but I am unsure
> whether this was followed up by anyone:
> - is an association a specialization of subject?
Yes. (Association is a type, therefore it is a subtype of the
universal type, which is subject.)
> - is a topic a specialization of subject?
> - is an occurrence (and a name) a specialization of association?
That's spelled out in TMDM. (And the answer is yes.)
> Things like these. So something like an "Ur-Ontology" for TMDM. I
> faintly remember that you had a blog entry in this direction but
> cannot reproduce it now.
> But once this is written somewhere (TMDM, TMRM, TMQL), then we would
> have a commitment.
This is the stuff I'm meant to put into the TMDM -> TMRM mapping.
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