# File lib/iq_rdf/uri.rb, line 21
    def initialize(namespace, uri_postfix, rdf_type = nil, lang = nil)
      raise "rdf_type has to be an IqRdf::Uri" unless rdf_type.nil? || rdf_type.is_a?(IqRdf::Uri)
      @namespace = namespace
      @uri_postfix = uri_postfix
      @rdf_type = rdf_type
      super(lang)
    end