Re: [xml-dev] RelaxNG schema validation - wildcard attributes andID type

[Jirka Kosek <jirka@kosek.cz>]

Svante Schubert wrote:

> The question is, does the tool have to act this way due to a specification?
> 
> The most relevant spec seems to be:
>    http://www.oasis-open.org/committees/relax-ng/compatibility.html#id
> But although I might misinterpret
>    http://www.oasis-open.org/committees/relax-ng/compatibility.html#IDAMYYR
> I would say no.

"A RELAX NG schema is compatible with this feature if and only if, after
schema simplification, for each data or value element that specifies a
datatype associated with a non-null ID-type, all of the following hold:

... if its attribute parent has any competing attribute elements, then
each such competing attribute element has a data or value child
specifying a datatype associated with the same ID-type."

If you have wildcard pattern then attribute coming from it is competing
with attribute of ID type.

> But what if the test:id attribute should be used in this arbitrary content?
> Does not "anyAttributes" refer to external attributes as well? It seems
> strange that only the internal IDs are being checked and why doing this
> check at all?
> It is odd to add an exclude to every attribute/anyName of a Schema,
> whenever a ID type attribute is being added.

I agree that this is issue which beaten me also several times, but in
many real world grammars it is sufficient to exclude just namespaces
defined in schema from wildcard pattern for elements. For example schema
for DocBook + MathML + SVG has to exclude those namespaces from wildcard
pattern:

namespace mml = "http://www.w3.org/1998/Math/MathML";
namespace db = "http://docbook.org/ns/docbook";
namespace svg = "http://www.w3.org/2000/svg";

include "/path/to/docbook.rnc" {
  db._any.mml = external "mahtml/mathml2.rnc"
  db._any.svg = external "svg/svg11.rnc"
  db._any =
    element * - (db:* | mml:* | svg:*) {
      (attribute * { text }
       | text
       | db._any)*
    }
}

This approach work well the only problem is that name classes are not
patterns so you have to redefine wildcard pattern each time, it is not
sufficient to extend pattern for (db:* | mml:* | svg:*) itself. But such
feature might be added into RELAX NG in the future, see:

http://wiki.oasis-open.org/relax-ng/FutureRequirements


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