[sc34wg3] Which set is the unconstrained scope? (SAM-issue 'scope-unconstrained-rep')

Bernard Vatant sc34wg3@isotopicmaps.org
Fri, 7 Jun 2002 23:16:49 +0200


Marc

> 1) It is kind of strange to put this in a standard like the SAM. It would
> either require Topic Map authors to reify their Topic Map, or have a Topic Map
> merge process do it for them. While it is certainly often useful to reify your
> Topic Map, _requiring_ it would seem unnecessary.

Reification might not be required. Another way would be (have been) to have <scope> as
direct child of <topicMap> itself.
And when this element is not explicited, then the default scope would be the reified
<topicMap>. or something like that.

> 2) What if you really want to say something that is valid always and
> everywhere? What if I want to express "The subject with identity 'MdG' has as
> its name 'Marc de Graauw', always and everywhere!" Your solution would
> automatically scope it down to the containing Topic Map.

Well ... "valid always and everywhere" is something I would never dare asserting.
Or publish a PSI for your notion of "always and everyhere" and use it as a scope.

> 3) It scales in strange way when we expand scope. Let me explain.
>
> When I have a topic map with:
> - a single genuine topic, name='Marc de Graauw'
> - a topic reifying the Topic Map, say 'The Scoping Problem Topic Map'
> - five themes, say 'nl', 'en', 'fr', 'de', 'es'

> First I have as the scope of the name 'Marc de Graauw' the set {nl}. Next I
> find that this name is valid in English as well, so I scope the name with {nl,
> en}.

Huh. Your proper name is not attached to you in a specific language. Why do you scope it
with your native language?

> Et cetera, the scope becomes  {nl, en, fr} and  {nl, en, fr, de}. Then I find
> the name is valid in Spanish as well, and since it is valid in all languages
> under scrutiny, I decide to say the name assignment is valid in the
> unconstrained scope.

OK. We meet here.

> Then I have as scope all of a sudden: scope = {The Scoping
> Problem Topic Map}. Alle the previous steps seem to bear a natural relation to
> each other, the last step does not. When (if) we want to build applications
> that are able to say: the scope {nl, en, fr} is a subset of the scope {nl, en,
> fr, de} and do something useful with that information? It would require special
> processing rules to do this with the reified Topic Map as scope because of this
> scaling problem.

I'm afraid I miss your point. Maybe we should test that on less academic examples :))

> It is certainly a useful approach, but I think it is more an approach for a
> Topic Map author, not one we could use in a standard. We could, however, say
> nothing in a standard about what the unconstrained scope is (solution 3 in my
> list), and let Topic Map authors use the solution you describe whenever they
> wish.

Hmmm. I don't know if it's a good idea. This scope issue is too tricky to let poor authors
deal with it :)

> There is another advantage: while the Topic Naming Constraint is
> under fire, it is very often useful (the more I think about it the better I
> like it). I think the problem is not so much the TNC but using the TNC *in the
> unconstrained scope*. Your approach would remove that problem.

I had not thought about it, but that seems to be true. Good point.

> Shoot!

"Same player shoots again"

Good night

Bernard