docs: @Override
      public final boolean has(Context cx, Object id) {
          if (cx == null) cx = Context.getCurrentContext();
          XMLName xmlName = lib.toXMLNameOrIndex(cx, id);
          if (xmlName == null) {
              long index = ScriptRuntime.lastUint32Result(cx);
              // XXX Fix this cast
              return has((int)index, this);
          }
          return hasXMLProperty(xmlName);
      }