namespace-uri - XPath
xslt/xpath reference: xslt elements, exslt functions, xpath functions, xpath axes the namespace-uri function returns a string representing the namespace uri of the first node in a given node-set.
... syntax namespace-uri( [node-set] ) arguments node-set (optional) the namespace uri of the first node in this node-set will be returned.

Introduction to using XPath in JavaScript - XPath
to match default elements in a non-null namespace, you either have to refer to a particular element using a form such as ['namespace-uri()='http://www.w3.org/1999/xhtml' and name()='p' and @id='_myid'] (this approach works well for dynamic xpath's where the namespaces might not be known) or use prefixed name tests, and create a namespace resolver mapping the prefix to the namespace.
... using xpath functions to reference elements with a default namespace another approach to match default elements in a non-null namespace (and one which works well for dynamic xpath expressions where the namespaces might not be known), involves referring to a particular element using a form such as [namespace-uri()='http://www.w3.org/1999/xhtml' and name()='p' and @id='_myid'].
... while one can adapt the approach in the above section to test for namespaced elements regardless of the prefix chosen (using local-name() in combination with namespace-uri() instead of name()), a more challenging situation occurs, however, if one wishes to grab an element with a particular namespaced attribute in a predicate (given the absence of implementation-independent variables in xpath 1.0).
...And 2 more matches

Document.createNSResolver() - Web APIs
to match default elements in a non-null namespace, you either have to refer to a particular element using a form such as *namespace-uri()=http://www.w3.org/1999/xhtml and name()=p[@id='_myid'] (this approach works well for dynamic xpath expressions where the namespaces might not be known) or use prefixed name tests, and create a namespace resolver mapping the prefix to the namespace.

Document.getElementsByTagNameNS() - Web APIs
(to accommodate explorer, one could call an xpath wrapper instead of the xpath in the function below (as explorer supports xpath with a different api), such as this wrapper class.) function getelementsbytagnamenswrapper (ns, elname, doc, context) { if (!doc) { doc = document; } if (!context) { context = doc; } var result = doc.evaluate('//*[local-name()="'+elname+'" and namespace-uri() = "'+ns+'"]', context, null, xpathresult.ordered_node_snapshot_type, null); var a = []; for(var i = 0; i < result.snapshotlength; i++) { a[i] = result.snapshotitem(i); } return a; } specifications specification status comment domthe definition of 'document.getelementsbytagnamens' in that specification.

Functions - XPath
boolean() ceiling() choose() concat() contains() count() current() xslt-specific document() xslt-specific element-available() false() floor() format-number() xslt-specific function-available() generate-id() xslt-specific id() (partially supported) key() xslt-specific lang() last() local-name() name() namespace-uri() normalize-space() not() number() position() round() starts-with() string() string-length() substring() substring-after() substring-before() sum() system-property() xslt-specific translate() true() unparsed-entity-url() xslt-specific (not supported) ...

Index - XPath
38 namespace-uri xslt, xslt_reference the namespace-uri function returns a string representing the namespace uri of the first node in a given node-set.

XPath snippets - XPath
ction function getxpathforelement(el, xml) { var xpath = ''; var pos, tempitem2; while(el !== xml.documentelement) { pos = 0; tempitem2 = el; while(tempitem2) { if (tempitem2.nodetype === 1 && tempitem2.nodename === el.nodename) { // if it is element_node of the same name pos += 1; } tempitem2 = tempitem2.previoussibling; } xpath = "*[name()='"+el.nodename+"' and namespace-uri()='"+(el.namespaceuri===null?'':el.namespaceuri)+"']["+pos+']'+'/'+xpath; el = el.parentnode; } xpath = '/*'+"[name()='"+xml.documentelement.nodename+"' and namespace-uri()='"+(el.namespaceuri===null?'':el.namespaceuri)+"']"+'/'+xpath; xpath = xpath.replace(/\/$/, ''); return xpath; } resources xpath forum discussion on this topic see also introduction to using xpath in javascrip...

The Netscape XSLT/XPath Reference - XSLT: Extensible Stylesheet Language Transformations
ns() (supported) count() (supported) current() (supported) document() (supported) element-available() (supported) false() (supported) floor() (supported) format-number() (supported) function-available() (supported) generate-id() (supported) id() (partially supported) key() (supported) lang() (supported) last() (supported) local-name() (supported) name() (supported) namespace-uri() (supported) normalize-space() (supported) not() (supported) number() (supported) position() (supported) round() (supported) starts-with() (supported) string() (supported) string-length() (supported) substring() (supported) substring-after() (supported) substring-before() (supported) sum() (supported) system-property() (supported) translate() (supported) true() (su...

Transforming XML with XSLT - XSLT: Extensible Stylesheet Language Transformations
pported) contains() (supported) count() (supported) current() (supported) document() (supported) element-available() (supported) false() (supported) floor() (supported) format-number() (supported) function-available() (supported) generate-id() (supported) id() (partially supported) key() (supported) lang() (supported) last() (supported) local-name() (supported) name() (supported) namespace-uri() (supported) normalize-space() (supported) not() (supported) number() (supported) position() (supported) round() (supported) starts-with() (supported) string() (supported) string-length() (supported) substring() (supported) substring-after() (supported) substring-before() (supported) sum() (supported) system-property() (supported) translate() (supported) true() (supported) unpars...