[sc34wg3] DM conformance

Lars Marius Garshol sc34wg3@isotopicmaps.org
21 Nov 2003 13:01:00 +0100

* Patrick Durusau
| Not sure what conformance is other than "using" the data model. If
| 13250-3 defined the same terms as 13250-2 differently and proceeded
| to use those terms, I would say it was not conforming to the data
| model.

I agree. But the same people are editing -2 and -3, and I can assure
you that they will do everything in their power to make sure there are
no inconsistencies.

If we were to include a "conformance statement" in -3 all that would
do would be to add the statement that "-3 conforms to -2", but it
would not *make* -3 conform to -2. We would do everything we could to
achieve that regardless of whether there was such a statement in -3 or
not, and so the standard itself would be exactly the same.

See what I mean? If we make a mistake we'll screw this up, but adding
a "conformance statement" will not prevent us from making mistakes.
| [re clause 1 of ISO 13250-2]
| Do we really want to say: "define the interpretation of the topic
| map interchange syntaxes..."?
| Seems to me that 13250-2 defines the interpretation of topic map
| interchange syntaxes and standards for canonicalization, querying,
| constraints, etc., that rely upon the data model.

What other syntaxes and standards could there be?
| Fully agree with you that the data model is providing a foundation
| and that anything that relies upon that foundation must of necessity
| be in conformance with it, but how do I (as a reader) know what
| foundation a particular standard claims?

Here's the Scope clause of the current ISO 13250-3 draft (not yet
published; working on that):

  This part of ISO/IEC 13250 defines an XML-based interchange syntax
  for topic maps, which can be used to interchange instances of the
  data model defined in [ISO 13250-2]. It also defines a mapping from
  the interchange syntax to the data model. The syntax is defined with
  a RELAX-NG schema, and more precision is provided through the
  mapping to the data model, which effectively also defines the
  interpretation of the syntax.

This answers the question, doesn't it?
| You could say it is obvious since it is all part of 13250 overall,
| but then one could make the same claim about the XML InfoSet. It is
| the only one at the W3C so what else would one be using for an XML
| standard.

Quite a lot, apparently, for which the W3C has been criticized, and in
my view correctly. They should have done the infoset first, and
everything else afterwards and based on it. For political reasons that
did not happen. We, however, are now in a position to avoid that
| The other problem is that I think we are construing the existence of
| topic map interchange syntaxes, querying, constraints, etc., with
| only those that appear from WG3. What if some third person wants to
| write a topic map interchange syntax? 

They can and have. If they define how their syntaxes map to the data
model you'll be able to see the relationship. If they don't you won't
be able to see it, but it may still be possible to set up a good

That is, they can follow the lead of 13250-3, or they can skip it and
just do something informally. Whichever way they go, I don't see how
adding a conformance statement in 13250-3 will change anything. 

| If we adopt the practice of having other parts of 13250 say they are
| conforming [...] to the data model, then we have set a practice in
| place for others to follow.

I believe we already do: ISO 13250-3 defines how the syntax it defines
maps to the DM. What more could you want?
| If topic maps become as successful as we all want, I don't think the
| interchange, querying and constraint languages of 13250 will be the
| only ones in existence.

We've already passed that point.

Lars Marius Garshol, Ontopian         <URL: http://www.ontopia.net >
GSM: +47 98 21 55 50                  <URL: http://www.garshol.priv.no >