public static Cons yieldCreationOrReuseTrees(Stella_Class renamed_Class) {
    { boolean usefreelistP = Stella_Class.useFreeListP(renamed_Class);
      boolean usesweeplistP = Stella_Class.useSweepListP(renamed_Class);

      if (usefreelistP &&
          usesweeplistP) {
        return (Stella_Class.yieldCreationOrReuseTreesFromFreeOrSweepList(renamed_Class));
      }
      else if (usefreelistP) {
        return (Stella_Class.yieldCreationOrReuseTreesFromFreeList(renamed_Class));
      }
      else if (usesweeplistP) {
        return (Stella_Class.yieldCreationOrReuseTreesFromSweepList(renamed_Class));
      }
      else {
        throw ((StellaException)(StellaException.newStellaException("Assuming CLASS uses at least one of Free-list or sweep-list").fillInStackTrace()));
      }
    }
  }