- From: Murata Makoto <EB2M-MRT@asahi-net.or.jp>
- Date: 13 Aug 2008 19:12:03 +0900
- To: public-xml-id@w3.org
- Cc: Michael.Brauer@sun.com, eb2m-mrt@j.asahi-net.or.jp
Dear colleagues,
I have a question about interactions of xml:id and
validation.
Consider a RELAX NG schema that defines xml:id as xsd:NCName rather
than xsd:ID and an DTD-free instance valid against this schema. The
schema does NOT use the RELAX NG DTD compatibility specification.
Since RELAX NG validation does not change the information set,
the [attribute type] property of the attribute xml:id is unknown.
I believe that there is nothing wrong in applying "ID attribute
normalization" and "ID type assignment" to xml:id in this instance
document. In my understanding, xml:id tries to separate ID processing
from validation as much as possible.
However, Section 4 of the xml:id recommendation says:
The declared type of the attribute, if it has one, is "ID".
All declarations for xml:id attributes must specify "ID" as
the type of the attribute.
Does this sentence prohibit my scenario? The pattern for xml:id
specifies xsd:NCName rather than xsd:ID.
Furthermore, what will happen if the xml:id attribute is validated
against wildcards? For example:
anyAtt = attribute * { xsd:string }.
Such wildcards are useful when we would like to allow foreign elements
to contain any attribute. Since the RELAX NG DTD compatibility
specification allows the use of xsd:ID only when we precisely know
the element name as well as the attribute name, we cannot
have:
anyElement = element * {attribute xml:id {xsd:ID}?, anyElement*}
If the "anyAtt" define statement shown above is what you mean
"declaration", we cannot allow xml:id within foreign elements
without giving up RELAX NG validation.
Cheers,
Makoto
Received on Wednesday, 13 August 2008 10:12:43 UTC