[sc34wg3] CTM Comments

[Lars Heuer]

Hi Robert,

[...]
> Ah! The way I had thought it would work is that ctm:self automatically
> expands to the baseURI of the map.

Ah! "ctm:self" was proposed to be a 'special' QName that generates a
topic with some (unique) identifier and the generated topic is
automatically set to the topicmap.reifier property.

> And using ~ would signal that this URI is used as subject
> identifier. Which is perfect for maps, not?

Not really. Problems:

    a) CTM does not use ~ for subject identifiers
    b) The reification mechanism has changed during the move from XTM
       1.0 to TMDM. "Reifier" is now a property of each Topic Maps
       construct which is not a topic and the XTM 1.0-reification
       procedure is not used anymore (a topic with subject identifier
       A reifies a Topic Maps construct with item identifier A).

> That way it would not be a "new syntax" such as

>   ~ mymap

The notation "~ mymap" isn't really new. CTM used "~ identifier" to
reify Topic Maps constructs. The thing that is 'new': We have to
enhance the CTM grammar that the notation "~ identifier" may be used
without a preceding Topic Maps construct and that we define it as
reification of the topic map instance.


[...]
>> Hmm.... The general agreement in Oslo was, that the reification
>> mechanism should not add too much syntax. BTW: CTM does not support
>> 'forward' reification, but even with "~" it should be possible to
>> support reification in both directions.

> How?

Because "~" does not have a direction. We could (but do not plan to)
allow this:

      assoc-reifier ~ assoc-type(type0: player0, type1: player1)

[...]
>> > - 3.9
>> 
>> >   I again propose that ""s are dropped where not necessary. I will
>> >   re-raise this as issue.
>> 
>> Personally I agree 100% with you, but CTM has other requirements and
>> the committee agrees that we need a consistent syntax for strings. The
>> notation won't change. "Der Drops is gelutscht"

> But it is still sour in the mouth :-)

> If there are no scope or reification for this, as in the 99% of the cases,
> then it is completely superfluous.

Not in all cases. I.e. a user can place the whole topic declaration in
one line:

    john - "John Lennon" - surname: "Lennon" homepage: http://....

Even I don't like that style it may be useful for compact topic maps /
exchanging topic declarations via IRC etc.

Best regards,
Lars
-- 
http://www.semagia.com