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What Namespace For Simple Types?

From: Sean B. Palmer <sean@mysterylights.com>
Date: Thu, 17 May 2001 02:12:50 +0100
Message-ID: <01f401c0de6e$84241560$08ed93c3@z5n9x1>
To: <xmlschema-dev@w3.org>
Cc: <w3c-wai-er-ig@w3.org>
Hi There,

The W3C WAI ERT group is currently creating a language called "EARL"
[1], and we are wanting to use a simple XSD datatype as the object of
one of our properties. We've created a new simple type from a union of
date and dateTime, and called it Date [2] (in our own namespace).
However, we're not at all sure what namespace to use (for the XSD
simple types) according to the XML Schema specification, mainly
because we're using RDF.

The issue here is partly about whether or not to use the "#" or not,
and partly whether or not to use the XML Schema namespace, or the XML
Schema datatypes namespace. On other words, we have the following
choices:-

   a) http://www.w3.org/2001/XMLSchema
   b) http://www.w3.org/2001/XMLSchema#
   c) http://www.w3.org/2001/XMLSchema-datatypes
   d) http://www.w3.org/2001/XMLSchema-datatypes#

The specification seems to recommend a) only for XSD specific
processors, b) for processors that use the XML Schema types but need
to create an URI reference, and c) for processors that don't recognize
the the XML Schema namespace. However, in the case of many RDF
processors, I think that both b) and c) are applicable, so you might
want to use d).

So, what namespace do you recommend? Even better, how should the XSD
datatype example in [2] be tweaked to provide maximum compatability
with XSD, RDF, and EARL specific processors?

[1] http://www.w3.org/2001/03/earl/
[2] http://lists.w3.org/Archives/Public/w3c-wai-er-ig/2001May/0037
Which contains the following snippet:-
   <xsd:schema
      xmlns="http://www.w3.org/2001/03/earl/0.95datatypes#"
      xmlns:xsd="http://www.w3.org/2000/10/XMLSchema"
      xml:lang="en" >
   <xsd:simpleType name="Date">
     <!-- Date is an XMLS union datatype -->
     <!-- values of Date may be either dates or dateTimes -->
     <xsd:union>
        <xsd:simpleType>
          <xsd:restriction base="xsd:date"/>
        </xsd:simpleType>
        <xsd:simpleType>
          <xsd:restriction base="xsd:dateTime"/>
        </xsd:simpleType>
     </xsd:union>
   </xsd:simpleType>
   </xsd:schema>

--
Kindest Regards,
Sean B. Palmer
@prefix : <http://webns.net/roughterms/> .
:Sean :hasHomepage <http://purl.org/net/sbp/> .
Received on Wednesday, 16 May 2001 21:09:57 GMT

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