static VALUE new(int argc, VALUE *argv, VALUE klass)
{
  xmlDocPtr xml_doc;
  xmlNodePtr node;
  VALUE document;
  VALUE content;
  VALUE rest;
  VALUE rb_node;

  rb_scan_args(argc, argv, "2*", &document, &content, &rest);

  if (rb_obj_is_kind_of(document, cNokogiriXmlNode))
  {
    document = rb_funcall(document, document_id, 0);
  }
  else if (   !rb_obj_is_kind_of(document, cNokogiriXmlDocument)
           && !rb_obj_is_kind_of(document, cNokogiriXmlDocumentFragment))
  {
    rb_raise(rb_eArgError, "first argument must be a XML::Document or XML::Node");
  }

  Data_Get_Struct(document, xmlDoc, xml_doc);

  node = xmlNewDocComment(
      xml_doc,
      (const xmlChar *)StringValueCStr(content)
  );

  rb_node = Nokogiri_wrap_xml_node(klass, node);
  rb_obj_call_init(rb_node, argc, argv);

  nokogiri_root_node(node);

  if(rb_block_given_p()) rb_yield(rb_node);

  return rb_node;
}