static <A> A nuLike too_thinkAndReturnFirstObjectOfType(Class<A> type, TransformersOnObjects too) {
  ret withDeepReturn(returnSite -> {
    // return first transformed input
    too.addTransformer(func(O o) {
      if (isInstance(type, o))
        deepReturn(returnSite, o);
      null;
    });
    too.think();
  });
}