xml-dev - Re: XML Schema Question: default namespace misses attributes

[Stefan Haustein <haustein@kimo.cs.uni-dortmund.de>]

Roger L.Costello wrote:
>
> Wouldn't it be better if, as is done in the XSLT spec, we don't use a
> default namespace and, instead, explicitly qualify all elements and
> attributes?  Using such an approach, the above example can be recast as:
> 
> <xsd:schema xmlns:xsd="http://www.w3.org/1999/XMLSchema" ...>
>     <xsd:element xsd:name="BookCatalogue">
>          ...
>     </xsd:element>
>     ...
> </xsd:schema>

The problem is that it makes a difference whether an attribute has 
a namespace or no namespace at all. The intention is probably to 
distinguish between namespace-global attributes that can occur in 
every element like xml:lang and attributes local to an element. 
Maybe the rationale behind that is that element-local attributes 
can have different meanings depending on the element, and 
may have no senseful meaning on their own. Putting
them in a global namespace would make look them more 
"global" than they are.

So, <xsd:element xsd:name="BookCatalogue"> would be expanded to

<{http://www.w3.org/1999/XMLSchema}element
{http://www.w3.org/1999/XMLSchema}name="BookCatalogue">

while <xsd:element name="BookCatalogue"> would be expanded to

<{http://www.w3.org/1999/XMLSchema}element {}name="BookCatalogue">

However, when you define the specs for a concrete XML application,
you are free to ignore the difference by regarding both cases
equal. I do not like the idea to of having namespaces for attributes 
very much because it seems to cause more confusion than benefit. 
Personally, I would prefer if the attributes' namespace would always 
default to the element's namespace.  

Best regards

Stefan