Return a serialization of this node as lexical XML
In the case of an element node, the result will be a well-formed XML document serialized as defined in the W3C XSLT/XQuery serialization specification, using options method="xml", indent="yes", omit-xml-declaration="yes".
In the case of a document node, the result will be a well-formed XML document provided that the document node contains exactly one element child, and no text node children. In other cases it will be a well-formed external general parsed entity.
In the case of an attribute node, the output is a string in the form
name="value". The name will use the original namespace prefix.
Other nodes, such as text nodes, comments, and processing instructions, are represented as they would appear in lexical XML.