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----- Original Message ----- From: "Francis Norton" <francis@r...> To: "Martin Gudgin" <marting@d...> Sent: Sunday, May 20, 2001 5:03 PM Subject: Re: Namespace: what's the correct usage? > [bought back on-list by permission!] > > Martin Gudgin wrote: > > > FN Wrote: > > > > > > This idiom is supported by XML Schema elementFormDefault="unqualified" > > > but to me it seems to redefine namespaces rather radically. There will > > > be complications when processing documents containing data from multiple > > > "namespaces" with clashing unqualified element names. > > > > Why? Surely at the point you come across the qualified element you figure > > out whether you recognise it or not. If not, then don't process that element > > and its descendants, skip to the next sibling. > > > Aha - but I have to explain that I am a fairly hardcore XSLT / XPath > user. Declarative, not sequential, but you're already having that > conversation with Jeni and David ... Yes, as noted earlier in this thread the declarative style does have bearing on the issue. > > > > > > > I suspect that it might be a good rule of thumb not to combine > > > elementFormDefault="unqualified" with xsd:any. > > > > I'm not sure why you think that. xsd:any takes a namespace attribue that > > allows the schema author to control what namespace(s) the replacement > > element(s) may come from. e.g. <xsd:any namespace='urn:x1' /> would only > > allow an element whose namespace name was 'urn:x1'. You *could* allow > > unqualified elements by saying <xsd:any namespace='##local' /> or <xsd:any > > /> ( which allows absolutely anything ). I agree that you would need to be > > careful in this latter situation. > > > Because <xsd:any namespace='urn:x1' /> might also be > elementFormDefault="unqualified" with local no-namespace elements, so > *all* the xsd:any options could introduce element name clashes in > no-namespace. But a such a wildcard would *only* be satisified by a qualified element in the correct namespace... Unqualified elements from a schema with the same value for the targetNamespace attribute would *not* satisfy such a wildcard... > > As a motivating example - I wrote an extractor to assemble a Schematron > schema from constraints embedded in XML Schema annotation/application > elements. Using "proper" namespace qualification gives scalability - > others can do what I've done without increasing conflict or complexity. > If I'd used the unqualified form I'd have to trust that no-one else did. > Or that if they did, that I was in a political position to make them > back off ... not really my idea of good practice. I'm not sure I understand the point you are making here... Gudge
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