Re: General concern about inter-grammar references

> you cannot write patterns like this:
>
> <group>
>  <choice>
>   <ref name="G2:foo"/>  <!-- reference to "foo" in G2 -->
>   <ref name="G3:bar"/>
>  </choice>
>  <choice>
>   <ref name="G2:foo"/>
>   <ref name="G3:bar"/>
>  </choice>
> </group>

You would need multiple <withGrammar> elements, but an implementation
doesn't have to reread for each <withGrammar>: <withGrammar> cannot override
named definitions, so an implementation can read a grammar once and keep a
table mapping URIs to grammars.

James