[sc34wg3] XTM 2.0 topicRef - proposal for an erratum

Lars Heuer heuer at semagia.com
Tue Oct 20 09:29:39 EDT 2009

Hi Lars,

Thanks for your answer.

>> That means the following references are illegal:
>> * <topicRef href="http://psi.example.org/puck-die-stubenfliege"/>

> Perhaps it should be, given that this is a reference to a subject  
> identifier?

:) Well, yes. But I tried to find a work-around for the problem that
it's not possible to reference a topic by its subject identifier. I
tried to use one of the subject identifiers as item identifier in the
assumption that the Topic Maps engine would merge the topics once it
has found the topic with the subject identifier. Anyway, that
work-around does not work (and XTM mandates the id attribute for
topics anyway).

>> * <topicRef href="puck-die-stubenfliege"/>

> This is a reference to a file with that name in the same directory,  
> and so very likely to be a mistake. In fact, one of the most common  
> errors in hand-written XTM files is leaving out the anchor first,  
> causing a stub topic to appear here.

Yeah, you're right. That was a bad example.

>> The limitation to IRI references with fragment identifiers carries an
>> unnecessary burden, especially if someone wants to generate topic maps
>> automatically.

> Maybe. I made an issue for this so we can track the discussion:
>   http://projects.topicmapslab.de/issues/1459

> Anyway, now that you've heard the rationale, what do you think?

I still think that avoiding this limitation would be good thing. I
could live with the limitation to IRI references with fragment
identifiers (the missing option to reference a topic by a subject
locator / identifier is more important for me), but the limitation
does not 'feel right' (even if I know the reasons now).

Best regards,

More information about the sc34wg3 mailing list