static <A extends Concept> A nuLike uniqCI_returnIfNew(Class<A> c, O... params) {
  Pair<A, Bool> p = uniqCI2(c, params);
  ret p.b ? p.a : null;
}

static <A extends Concept> A nuLike uniqCI_returnIfNew(Concepts cc, Class<A> c, O... params) {
  Pair<A, Bool> p = uniqCI2(cc, c, params);
  ret p.b ? p.a : null;
}