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xmlsch issues discussion

From: Dave Beckett <dave.beckett@bristol.ac.uk>
Date: Wed, 12 Mar 2003 11:49:41 +0000
To: w3c-rdfcore-wg@w3.org
Message-ID: <5424.1047469781@hoth.ilrt.bris.ac.uk>


The chairs will have to rule on whether my claims below that some of
these comments are out of scope/charter are on target.


ISSUE http://www.w3.org/2001/sw/RDFCore/20030123-issues/#xmlsch-08

>    We believe there are probably good reasons for using an rdf:datatype
>    attribute, instead of re-using the existing xsi:type attribute which
>    has (when the type is defined in a schema defined by XML Schema 1.0)
>    the same semantics.In particular, rdf:datatype does not assume or
>    assert the existence of the type named as a type in a schema defined
>    by XML Schema, so it would be problematic to use xsi:type.

Just commentary, no discussion or changes required.  We also agree
there are good reasons that xsi:type as designed is not appropriate
for RDF/XML which uses with URIs for datatypes, not qnames.  Maybe
the XML schema WG wants to hear more reasons why xsi:type wasn't
used?

>    We do fear, however, that users are likely to find this
>    near-duplication of the meaning and function of xsi:type confusing. It
>    is not clear to us what, if anything, can or should be done to
>    minimize this danger.

The Primer is the place that users can already look for to see how to
write RDF datatypes in the RDF/XML syntax:
  http://www.w3.org/TR/2003/WD-rdf-primer-20030123/#typedliterals
  http://www.w3.org/TR/2003/WD-rdf-primer-20030123/#example7
  http://www.w3.org/TR/2003/WD-rdf-primer-20030123/#example22

There is already discussion near figure 9
  http://www.w3.org/TR/2003/WD-rdf-primer-20030123/#figure9

Summary: closed. explanation, no action



ISSUE http://www.w3.org/2001/sw/RDFCore/20030123-issues/#xmlsch-09

> "We were unable, on a first reading, to determine whether the default
>    namespace declaration, and thus unprefixed names, were or were not
>    allowed in order to encode 'RDF URI References'."

That XML detail is discussed in "The Syntax Data Model Section"
where it already states in the fifth paragraph:

  "The syntax does not support non-well-formed XML documents, nor
  documents that otherwise do not have an XML Information Set; for
  example, that do not conform to XML Namespaces [XML-NS]."
  -- http://www.w3.org/TR/2003/WD-rdf-syntax-grammar-20030123/#section-Data-Model

So if there is no namespace name, it isn't RDF/XML.

Summary: closed. explanation, no action


ISSUE http://www.w3.org/2001/sw/RDFCore/20030123-issues/#xmlsch-10
"cannonical syntax"

Discussion of out of what I believe is out of RDF Core's charter,
creating a new XML syntax or modifying RDF/XML (created 1998)
to work with XML technology designed later.

  "The RDF Core WG is neither chartered to develop a new RDF syntax,"
  -- http://www.w3.org/2001/sw/RDFCoreWGCharter

Summary: closed.  we don't have to do this, out of charter ??



ISSUE http://www.w3.org/2001/sw/RDFCore/20030123-issues/#xmlsch-11
"layering on xml"

There is some explanation to do since they seem to have missed
reading the Syntax Data model section in defining RDF/XML on top of
the pile of XML technologies.

>    Not only does this confuse levels and thus readers, it also runs the
>    risk of inadvertently defining an XML subset. It also appears, on a
>    strict reading, to rule out XML documents not derived from the parsing
>    of character streams as possible RDF/XML (so that it would be
>    illegitimate to regard a data structure created using a DOM interface,
>    for example, as RDF/XML).

It neither creates a subset nor rules out using other XML APIs as
long as an XML Infoset is available.

  "This model illustrates one way to create a representation of an
  RDF Graph from an RDF/XML document. It does not mandate any
  implementation method - any other method that results in a
  representation of the same RDF Graph may be used.

  In particular:
  ...
   * This specification does not require the use of [XPATH] or [SAX2]
   * This specification places no constraints on the order in which
  software transforming RDF/XML into a representation of a graph,
  constructs the representation of the graph. 
  "
  -- http://www.w3.org/TR/2003/WD-rdf-syntax-grammar-20030123/#section-Data-Model

Action: closed. explanation, no changes
    

ISSUE http://www.w3.org/2001/sw/RDFCore/20030123-issues/#xmlsch-12
"capricious syntax"

Discussion and proposal for a better XML syntax (RDF/XML 1998) to
better match the RDF concepts and abstract syntax (2002).  Out of
charter:

  "The RDF Core WG is neither chartered to develop a new RDF syntax,"
  -- http://www.w3.org/2001/sw/RDFCoreWGCharter

Comments on the problems W3C XML schema (designed 1999/2000), XSLT
and XQuery has dealing with RDF/XML and its many variations.

Long comments on difference between XML and RDF data models meaning
different tool sets.  Tree (sort of) and graph.  We knew that.

Proposal to work together to create new XML serializations.

Action: closed
  out of charter/scope??,
  coordination group work??
  joint work / postponed work / feedback to new activities??

Dave
Received on Wednesday, 12 March 2003 06:50:37 EST

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