docs: public void addOptionalExcludedName(String name) {
          Object obj = lookupQualifiedName(scope, name);
          if(obj != null && obj != UniqueTag.NOT_FOUND) {
              if (!(obj instanceof Scriptable)) {
                  throw new IllegalArgumentException(
                          "Object for excluded name " + name +
                          " is not a Scriptable, it is " +
                          obj.getClass().getName());
              }
              table.put(obj, name);
          }
      }