[topicmapmail] XTM Datatypes [Was: Adding weigths to associations]

[Murray Altheim]

Martin Bryan wrote:

> Lars
> 
>>(What I am trying to say between the lines here is that transformation
>>from a custom TM syntax to XTM is just like any other kind of XML2XML
>>transformation, and so I don't really see it as something that should
>>be part of ISO 13250. If you disagree then I would like to hear your
>>arguments.)
> 
> Not if the custom TM is based on 13250 architectural forms that are not
> supported in XTM, e.g. facets. XTM also requires the creation of extra
> "topics" to be created to cover the roles used in 13250.


The creation of extra topics isn't exactly a showstopper, and I believe

there are ways of representing facets, though certainly they *could*
have been included in XTM. They weren't. There was ample discussion
on the issue for quite a long time, and it seems sour grapes to bring
that up once again.

 
>>What Tony and Kal were talking about was embedding non-topic map XML
>>in XTM <resourceData>. I assume that is not what you are asking for?
> 
> I do actually need this. If I need to italicise or embolden one or more
> elements in a name, or I need to provide a prompt to help people interpret
> occurrence indicators. For example, my occurrence indicator prompts include
> names of publications that should be italicised. Personally I don't believe
> this option should be restricted to resourceData. There is certainly no such
> restriction in 13250.


No, how could there be such a restriction? ISO 13250 provided a
meta-DTD, not an XML interchange syntax. By the same approach,
13250 allowed absolutely ANY markup that could be tagged as topic
map information. Obviously there is no way to support this as an
approach. If you want italics, somebody else may want the entire
set of XHTML inline elements, including <object> and <script>.
Somebody else may want to include SVG elements. There is obviously
no end to the possibilities.


Another way to do this would be to point to an <svg> element or

some markup representing the resource, which is what XTM's
<resourceRef> is all about. If you have an application that can
grok SVG or <i>, then it can certainly transclude the content
you're pointing to. I do this with the current version of my
ontology editor, extracting Dublin Core-tagged (in attributes)
content to populate a form rendition of a topic. It's not very
difficult.

If we open up XTM to allow any form of markup whatsoever, we
completely destroy the processing model for interchange, and
begin to travel down the road of non-interoperable topic map
documents, which was not the intention of XTM. It's always
somebody's option to create their own proprietary customization
of topic map syntax, or some customization of XTM. There's
still the ISO 13250 meta-DTD if you want to create your own,
or you could use XSLT to perform transformations to and from
valid XTM, say, transcluding namespaced content within an XTM
document, then using an extraction stylesheet to decompose it
for interchange.

Murray

......................................................................
Murray Altheim                  <http://kmi.open.ac.uk/people/murray/>
Knowledge Media Institute
The Open University, Milton Keynes, Bucks, MK7 6AA, UK

            If you're the first person in a new territory,
            you're likely to get shot at.
                                                     -- ma