Re: Boeing XRI Use Cases

Thanks,

I think I understand what you are getting at with the definition of  
"anyURI"  in XSD 1.1 being a superset of  valid namespace declarations  
in Namespace Recommendations.

Sorry for the confusion.

John Bradley

On 6-Aug-08, at 3:07 PM, noah_mendelsohn@us.ibm.com wrote:

> Let me respond to your points in reverse order, as the 2nd seems to  
> be the
> more fundamental:
>
>> Perhaps some mention should be made in http://www.w3.org/TR/xml-names11
>> that it is no longer authoritative.
>>
>> I guess that makes the answer to Julian's original question.
>>
>> No http://www.w3.org/TR/xml-names11/ is not "the namespaces
>> specification for XML 1.1", http://www.w3.org/TR/xmlschema11-2/
>> should be used.
>
> No, that's not the case.  The XML Namespaces Recommendations  
> continue to
> be the normative source on what is and is not a legal namespace in  
> an XML
> document.  XML Schema does define an anyURI type that is intended to  
> be
> useful to signal that a given datum is intended to be a URIs and/or  
> IRI.
> IWe realized early that schema datatypes could provide practical
> validation rules that would in fact reject all illegal IRIs while
> accepting all correct ones.  As a trivial example, the URI  
> specifications
> delegate to the specifications for particular schemes for syntax  
> details,
> and we knew there was no way we wanted to put in separate rules for  
> http,
> mailto, tel, etc.  XSD 1.0 broadly indicates that the strings were  
> to be
> validated as URIs, but realizing that this was a fuzzy and ultimately
> impractical burden to put on processors, the rules are loosened in XSD
> 1.1, which now accepts any string of legal XML characters.
>
> I have tried to be careful that when responding to email questions  
> in this
> thread about legal namespaces I've referred to the Namespaces
> Recommendation, and where questions have been raised about XSD  
> anyURI I've
> given the rules for that.  I believe I did mention once that  
> xsd:anyURI
> can be used to validate namespaces, but I meant that only to  
> indicate that
> IRIs are not excluded.  The normative rules for namespaces continue  
> to be
> in the Namespaces Recommendations.
>
>> So I conclude that contrary to http://www.w3.org/TR/xml-names11/#reluri
>> , the recommendation
>> http://www.w3.org/2000/09/xppa  is not making it into XSD 1.1?
>
> Again, we're crossing up Namespaces Recommendations and XSD 1.1.  The
> pertinent normative reference is
> http://www.w3.org/TR/xml-names11/#iri-use, which says:
>
> "The use of relative IRI references, including same-document  
> references,
> in namespace declarations is deprecated. "
>
> XSD 1.1 in no way supercedes that.  It merely defines a type that  
> can be
> used to declare one's intention that a data value be considered as an
> IRI/URI.  The validation semantics are, for better or worse,  
> essentially a
> no-op, but those affect only what will be accepted during schema
> validation.  They in no way alter what's a legal URI, IRI or namespace
> name, or remove the deprecation of relative namespace names.
>
> Noah
>
> --------------------------------------
> Noah Mendelsohn
> IBM Corporation
> One Rogers Street
> Cambridge, MA 02142
> 1-617-693-4036
> --------------------------------------
>
>
>
>