@Override
 public RAbstractVector tryFoldConstantTime(RAbstractVector operand, int operandLength) {
   if (arithmetic instanceof Plus) {
     return operand;
   } else if (arithmetic instanceof Negate && operand instanceof RSequence) {
     if (operand instanceof RIntSequence) {
       int start = ((RIntSequence) operand).getStart();
       int stride = ((RIntSequence) operand).getStride();
       return RDataFactory.createIntSequence(
           applyInteger(start), applyInteger(stride), operandLength);
     } else if (operand instanceof RDoubleSequence) {
       double start = ((RDoubleSequence) operand).getStart();
       double stride = ((RDoubleSequence) operand).getStride();
       return RDataFactory.createDoubleSequence(
           applyDouble(start), applyDouble(stride), operandLength);
     }
   }
   return null;
 }