docs: public static long reduce(
          LongTuple t0, long identity, LongBinaryOperator op)
      {
          long result = identity;
          int n = t0.getSize();
          for (int i=0; i<n; i++)
          {
              long operand0 = t0.get(i);
              result = op.applyAsLong(result, operand0);
          }
          return result;
      }