Re: [ubl-dev] The announcement of RELAX NG Schema library for UBL 1.0Beta

[Hiroshi Naito <naitoh@is.oit.ac.jp>]

Hi Duane,

Thanks for your interest in our study.

Multiplicity descriptions of W3C XML Schema can be easily translated to
the equivalent RELAX NG schema codes by repeating RELAX NG <optional> and
<ref> tags. Another approach is using "short-hand" notations and translating 
program such as KAWAGUCHI's RELAX NG short-hand processor. 

http://www.geocities.com/kohsukekawaguchi/relaxng/shorthand/ShortRNG.html

W3C XML Schema has two kinds of type derivation, extension and 
restriction. Extension is supported by RELAX NG, but restriction is not. 
Restriction can be implemented by generating replaced RELAX NG codes 
from the based schema description.

It must be noticed that UBL applications need PSVI (post-schema-validation infoset),
especially type hierarchy information for schema customizations, 
versioning and code list handling. RELAX NG is a pattern-oriented schema 
language, then do not have a concept of type and type derivation.

http://www.idealliance.org/papers/dx_xml03/papers/04-04-04/04-04-04.pdf

Also we notice that RELAX NG does not have some features for describing 
large schema library, such as the management of pattern names with
namespace and import other schema file.

We will post detailed reports to this ML.

Thanks

Naito

At 06:16 2004/03/18 -0800, Duane Nickull wrote:
> Kon'nichi-wa Naito-san:
> 
> I would add one more requirement to your list if possible.  I would 
> think that Relax-NG must also be capable of expressing the same level of 
> constraints as W3C Schema (for instance - expressing multiplicity and 
> datatype constraints).
> 
> This is a very large task you are undertaking.  Thank you for your efforts.
> 
> Duane Nickull


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Hiroshi Naito, Osaka Institute of Technology <http://www.oit.ac.jp/>