private static<REAL, NODE extends LeafNode<REAL>> List<REAL> realList(List<NODE> nodes) {
        List<REAL> reals = new ArrayList<>();
        for(NODE node : nodes) {
            reals.add(node.value());
        }
        return Collections.unmodifiableList(reals);
    }
Creates a new Node by cloning the default node.
config-lib/src/main/java/com/yahoo/config/LeafNodeVector.java