anchor.diff:              default:
                   throw "Invalid input for num conversion";
           }
  +
  +        if (_value is double)
  +            type = 0;
  +        else
  +            type = 1;
       }
   
       value() => _value;
  
positive.code:     final _stop, _step;
  
      $RangeIterator(pos, stop, step) : _stop = stop, _pos = pos - step, _step = step;
  
      get current => _pos;
  
      bool moveNext() {
  
negative.code:     var _value, type;
  
      $PyNum(value) {
          switch ($getType(value)) {
              case 6:
                  _value = value;
                  break;
  