def value
      if resource?
        uri
      elsif blank?
        Redland.librdf_node_get_blank_identifier(rdf_node).force_encoding("UTF-8")
      else
        v = Redland.librdf_node_get_literal_value(rdf_node).force_encoding("UTF-8")
        v << "@#{lang}" if lang
        XmlSchema.instantiate(v, datatype)
      end
    end
def value
      if resource?
        uri
      elsif blank?
        Redland.librdf_node_get_blank_identifier(rdf_node).force_encoding("UTF-8")
      else
        v = Redland.librdf_node_get_literal_value(rdf_node).force_encoding("UTF-8")
        v << "@#{lang}" if lang
        XmlSchema.instantiate(v, datatype)
      end
    end
Value of the literal node as a Ruby object instance.

 Returns an instance of URI for resource nodes,
 "blank identifier" for blank nodes.

 @return [URI, Any]