Returns the local part of the name of $arg as an xs:string that will either be the zero-length string or will have the lexical form of an xs:NCName.
If the argument is omitted, it defaults to the context node. If the context item is undefined an error is raised: [err:XPDY0002]. If the context item is not a node an error is raised: [err:XPTY0004].
If the argument is supplied and is the empty sequence, the function returns the zero-length string.
If the target node has no name (that is, if it is a document node, a comment, a text node, or a namespace node having no name), the function returns the zero-length string.
Otherwise, the value returned will be the local part of the expanded-QName of the target node (as determined by the dm:node-name accessor in Section 5.11 node-name Accessor[DM]. This will be an xs:string whose lexical form is an xs:NCName.
var x = xdmp.unquote('<a:name xmlns:a="a"/>')
.toArray()[0].root.xpath("/element()");
fn.localName(x);
=> hello