(if (valid-iri? iri) iri (throw 'invalid-iri iri))))))

(define (parse-object object state)

  (match object

    (('literal ('string-literal-quote ("^^" iri)))

     (let* ((iri (parse-iri iri state))

(define (parse-nquads-doc parse-tree state)

  (let loop ((parse-tree parse-tree) (state state) (default-graph '())

                                     (named-graphs '()))

    (match parse-tree

      ('() (make-rdf-dataset default-graph named-graphs))

      ((('statement statement ...) parse-tree ...)