mrb_respond_to(mrb_state *mrb, mrb_value obj, mrb_sym mid)
{
  return mrb_obj_respond_to(mrb, mrb_class(mrb, obj), mid);
}
mrb_respond_to(mrb_state *mrb, mrb_value obj, mrb_sym mid)
{
  return mrb_obj_respond_to(mrb, mrb_class(mrb, obj), mid);
}