code: @Override
      public void resolve(final ValueStack values) throws Exception
      {
          if (values.size() < 2)
              throw new Exception("missing operands for " + toString());
  
          try
          {
              String adjustments = "";
  
              if (getParameterCount() == 3)
                  adjustments = values.popString();
  
              final DateTimeFormatter dtf = DateTimeFormatter.ofPattern(values.popString());
  
              final String dateInputObject = values.popString();
              final LocalDateTime convertedInputDate = LocalDateTime.parse(dateInputObject, dtf);
  
              values.push(CalendarFactory.modify(convertedInputDate, adjustments));
  
          } catch (final ParseException e)
          {
              e.fillInStackTrace();
              throw new Exception(toString() + "; " + e.getMessage(), e);
          }
      }
docs: {@inheritDoc}