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Re: XML Schema Question: default namespace misses attributes

From: james anderson <james.anderson@mecomnet.de>
Date: Wed, 09 Feb 2000 11:35:23 +0100
Message-ID: <38A142E9.890C0B8@mecomnet.de>
To: xml-dev@xml.org
CC: www-xml-schema-comments@w3c.org


Andrew Layman wrote:
> 
> ...
> 
> With particular reference to to discussion below, the specification does not
> use phrasing like "in a namespace". (Actually, it does, once, but only as a
> comment to an example.) What the specification does do is provide syntax to
> associate qualified names with URIs, thereby allowing certain names to be
> universalized.
> 
> ... the starting point for doing this is to read what
> is literally written there.
> 

 That's what I keep trying to do. The problem is, when I do that, I
discover concepts which are difficult to reconcile with the ancilliary
proposals and discussions.
 For example (from REC-xml-names-19990114):


"[Definition:] An XML namespace is a collection of names, identified by
a URI reference [RFC2396], which are used in XML documents as element
types and attribute names. XML namespaces differ from the "namespaces"
conventionally used in computing disciplines in that the XML version has
internal structure and is not, mathematically speaking, a set. These
issues are discussed in 'A. The Internal Structure of XML Namespaces'."

 or

"5.2 Namespace Defaulting

A default namespace is considered to apply to the element where it is
declared (if that element has no namespace prefix), and to all elements
with no prefix within the content of that element. If the URI reference
in a default namespace declaration is empty, then unprefixed elements in
the scope of the declaration are not considered to be in any namespace.
Note that default namespaces do not apply directly to attributes."


 The concepts of "namespace as collection" and "membership in a
collection" would appear to be present in the specification. If there
were to ever be a revised draft, perhaps it would work out their
implications and thereby avoid such unpleasantries as those in the
schema proposal for the purpose of identifying "names in no namespace".
Received on Wednesday, 9 February 2000 05:30:54 GMT

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