[Bug 4632] Use of IRIs

http://www.w3.org/Bugs/Public/show_bug.cgi?id=4632





------- Comment #2 from pratul.dublish@microsoft.com  2007-09-07 02:51 -------
Here's a suggestion to resolve this bug.

Given the decision at Toronto F2F to require XML Schema 1.0 for SML 1.1 (i.e., 
XML Schema 1.0 must be supported, but implementations are not prevented from
using XML Schema 1.1), it may be better to continue using URI as the
interoperable reference scheme in SML IF since it aligns with the definition of
xs:anyURI in XML Schema 1.0

3.2.17 anyURI

[Definition:]   anyURI represents a Uniform Resource Identifier Reference
(URI). An anyURI value can be absolute or relative, and may have an optional
fragment identifier (i.e., it may be a URI Reference). This type should be used
to specify the intention that the value fulfills the role of a URI as defined
by [RFC 2396]<http://www.w3.org/TR/xmlschema-2/#RFC2396>, as amended by [RFC
2732]<http://www.w3.org/TR/xmlschema-2/#RFC2732>.

The mapping from anyURI values to URIs is as defined by the URI reference
escaping procedure defined in Section 5.4 Locator
Attribute<http://www.w3.org/TR/2001/REC-xlink-20010627/#link-locators> of [XML
Linking Language]<http://www.w3.org/TR/xmlschema-2/#XLink> (see also Section 8
Character Encoding in URI
References<http://www.w3.org/TR/2001/WD-charmod-20010126/#sec-URIs> of
[Character Model]<http://www.w3.org/TR/xmlschema-2/#CharMod>). This means that
a wide range of internationalized resource identifiers can be specified when an
anyURI is called for, and still be understood as URIs per [RFC
2396]<http://www.w3.org/TR/xmlschema-2/#RFC2396>, as amended by [RFC
2732]<http://www.w3.org/TR/xmlschema-2/#RFC2732>, where appropriate to identify
resources.


The above approach allows SML and SML IF implementations to leverage the
xs:anyURI support built into XML Schema 1.0 processors. Note that URI reference
escaping mechanism allows internationalized resource identifiers to be
specified as anyURI although the specification may not be as elegant as that
for IRIs.

If the WG still wants to pursue IRIs, then we'll need to define a new datatype
- say smlif:anyIRI - to capture the definition of xs:anyURI in XML Schema 1.1.

3.3.18 anyURI

[Definition:]   anyURI represents an Internationalized Resource Identifier
Reference (IRI).  An anyURI value can be absolute or relative, and may have an
optional fragment identifier (i.e., it may be an IRI Reference).  This type
should be used when the value fulfills the role of an IRI, as defined in [RFC
3987]<http://www.w3.org/TR/xmlschema11-2/#RFC3987> or its successor(s) in the
IETF Standards Track.
Note: IRIs may be used to locate resources or simply to identify them. In the
case where they are used to locate resources using a URI, applications should
use the mapping from anyURI values to URIs given by the URI reference escaping
procedure defined in Section 3.1 Mapping of IRIs to
URIs<http://www.ietf.org/rfc/rfc3987.txt> of [RFC
3987]<http://www.w3.org/TR/xmlschema11-2/#RFC3987> or its successor(s) in the
IETF Standards Track.  This means that a wide range of internationalized
resource identifiers can be specified when an anyURI is called for, and still
be understood as URIs per [RFC
3986]<http://www.w3.org/TR/xmlschema11-2/#RFC3986> and its successor(s).


Most SML validators will need to add support for the above since the above
definition is not supported by XML Schema 1.0 processors.

Received on Friday, 7 September 2007 02:51:29 UTC