classThis class is an implementation of['a node #extension as 'a]namespace_element_impl :'a ->['a]node
node which
realizes element nodes. In contrast to element_impl, this class
also implements the namespace methods.
This class has an extended definition of the create_element method.
It accepts element names of the form "normprefix:localname" where
normprefix must be a prefix managed by the namespace_manager. Note
that create_element does not itself normalize prefixes; it is expected
that the prefixes are already normalized.
In addition to calling create_element, one can set the namespace scope
after creation (set_namespace_scope) to save the mapping of unprocessed
namespace prefixes to normalized prefixes. This is voluntary.
Such nodes have the node type T_element "normprefix:localname".
This class implements the namespace methods.
