Alternative approach to ITS validation

Hi folks,

Felix invited me to join ITS group and I think that I should bring some
new ideas to the table thus.

One of field of my interests is validation. The current ITS
specification offers two means of validation of ITS instances. One is
based on Schematron and it is able to validate any document with embeded
ITS markup, but only very basic tests are done. The second method
assumes that you will create custom schema which will combine your
markup with ITS markup and you can use provided schema modules to make
this work easier.

I think that we should also provide third method which will be able to
check ITS markup in any document (be it XHTML, DocBook, TEI, or
whatever) without need of creating custom schemas.

There is a nice validation language NVDL
(http://standards.iso.org/ittf/PubliclyAvailableStandards/c038615_ISO_IEC_19757-4_2006(E).zip)
which is perfectly suited for this task. In NVDL you can easily specify
against which schema elements/attributes from particular namespace
should be validated. NVDL is already in use by other W3C WGs -- for
example SVG 1.2 uses NVDL.

I quickly created prototype of NVDL schema for ITS (its.nvdl). Basically
this schema says that elements from ITS namespace should be validated
against its-elements.rng schema, which just includes existing its.rng
schema and says that only elements its:rules, its:span and its:ruby are
allowed as top-level containers in foreign document. Moreover NVDL
schema defines that if there is an attribute from ITS namespace on a
foreign element than this attribute must be one of its:version,
its:translate, and so on. Other elements and attributes are ignored
during validation.

If you want to test this proposed method yourself you will need NVDL
implementation. List of implementations is available at
http://nvdl.org/. I would recommend you to use oNVDL, because I
discovered little bug in JNVDL while testing my schema. This bug will be
fixed soon (btw JNVDL is developed by one of my students), but for now
you will get more errors then you should on some testing instances. If
you would like to use some sort of point and click interface you can use
oXygen XML Editor. Starting from version 8 it is shipped with built-in
NVDL support.

I would like to hear comments about my proposed validation solution. If
you like the idea of using NVDL I think that we should add NVDL schema
as a non-normative appendix to the specification.

Of course I plan to do more testing, this is just first, quick proposal.
Because I'm new to this WG and I do not know all infrastructure yet, I
would like to know if there is some sort of repository from which I
should easily fetch all sample ITS documents which are presented in the
specification. Of course I can save them manually one-by-one from
specification, but grabbing all of them once would be nice.

I'm looking forward for your comments,

					Jirka


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  Jirka Kosek     e-mail: jirka@kosek.cz     http://www.kosek.cz
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