Copying namespaces in XQuery - xquery

Question

I'm trying to construct a new element based on an old one, including copying in its children. To prevent each child from repeating the namespace definitions for each namespace in scope, I'm interested in copying the namespace declarations as well.
Namespace declarations aren't picked up as regular attributes through $element/#*.
If I restrict my code to only work with XQuery 3.0, I can do the following:
<new-element>
{
for $ns-prefix in in-scope-prefixes($element)
let $ns-uri := namespace-uri-for-prefix($ns-prefix, $element)
return namespace { $ns-prefix } { $ns-uri }
}
...
</new-element>
Is there a better way?
To clarify the problem a bit -- my original document looks like so:
<root xmlns:stuff="...">
<child name="foo"/>
<child name="bar"/>
</root>
When I copy children into a new document, I get the following:
<new-element>
<child xmlns:stuff="..." name="foo"/>
<child xmlns:stuff="..." name="bar"/>
</new-element>
...whereas it would make more sense to simply attach the xmlns:stuff declaration to <new-element>.

Answer 1

If you permit use of XQuery Update, you could use a transform expression (copy/modify/return) to copy the node, then modify the name.

Answer 2

In XQuery 3.0, the following should work if your implementation supports the namespace axis (which I believe is an optional feature):
<new-element>
{$element/namespace::*}
...
</new-element>

Answer 3

If you use programmatic constructors, I believe they take care of the namespace declarations in the way you need.
xquery version "1.0";
declare function local:transform($node)
{
typeswitch($node)
case element()
return element { fn:node-name($node) } {
$node/#*,
for $n in $node/*
return local:transform($n)
}
default return $node
};
let $node :=
<dmc:root xmlns:dmc="http://davidcassel.net/dmc">
<dmc:parent attr="value">
<stuff:child xmlns:stuff="http://davidcassel.net/stuff">some text</stuff:child>
</dmc:parent>
</dmc:root>
return local:transform($node)
Running that produces
<dmc:root xmlns:dmc="http://davidcassel.net/dmc">
<dmc:parent attr="value">
<stuff:child xmlns:stuff="http://davidcassel.net/stuff"/>
</dmc:parent>
</dmc:root>
Add cases to the typeswitch to make the structural changes you want. Does that accomplish what you're looking for?
Tested on MarkLogic 5 using standard XQuery 1.0.

Answer 4

I had a similar problem, and simply added a "fake" attribute to the parent node in the namespace, which causes it to pick up the declaration at that level.
<new-element stuff:something="anything">
...
</new-element>