PREFIX rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

<http://a.example/n1> <http://a.example/p1> _:l0 .
_:l0 rdf:first <http://a.example/v1> .
_:l0 rdf:rest _:l1 .
_:l0 rdf:comment "not allowed" .
_:l1 rdf:first <http://a.example/v2> .
_:l1 rdf:rest _:l2 .
_:l2 rdf:first <http://a.example/v3> .
_:l2 rdf:rest rdf:nil .