Returns a singleton node-list comprising the node in nnl whose
name is string, if there is such a node, and otherwise returns the
empty node-list.
string is normalized according to the string normalization
rule associated with nnl before being compared to the names
of the members of nnl.
(named-node-list-normalize string nnl symbol)
Returns string normalized according to the normalization rule of
the named node list nnl applicable to nodes of class symbol.
(named-node-list-names nnl)
Returns a list of the names of the members of nnl in the same
order as nnl. The result shall be a list of strings with the same
number of members as nnl.