[sc34wg3] 4.3 Constraints

[Patrick Durusau]

Greetings,

Since we are discussing conformance, I have a question about 4.3 
Constraints, which reads:

*********4.3 Constraints**********
The model defined in this this part of ISO/IEC 13250 contains not only 
fundamental types and information item types with named properties, but 
also constraints on the allowed instances of the model. The purpose of 
these constraints is to prevent inconsistencies in instances of the data 
model.
*******/4.3 Constraints***********

This seems to be related to our discussion on conformance with the data 
model.

If we don't have conformance or as Lars as said, what does it mean to 
conform to a data model, then the data model can't very well constrain 
"allowed instances of the model." To say it another way, an instance of 
the model either uses the data model as given or its doesn't. (BTW, what 
are instances of the model?)

Hence my redundant proposal (following a much earlier one by SRN), to 
follow the practice of the W3C with regard to the InfoSet. At least in 
that case I don't have to guess whether a particular XML standard 
follows the InfoSet or not, and, more importantly for me, I know where 
it departs from the InfoSet.

BTW, I missed the "constraints on the allowed instances of the model" 
part. Pointers anyone?

Hope everyone is having a great day!

Patrick

-- 
Patrick Durusau
Director of Research and Development
Society of Biblical Literature
Patrick.Durusau@sbl-site.org
Chair, V1 - Text Processing: Office and Publishing Systems Interface
Co-Editor, ISO 13250, Topic Maps -- Reference Model

Topic Maps: Human, not artificial, intelligence at work!