code: public function cellExists($pCoordinate)
      {
          // Worksheet reference?
          if (strpos($pCoordinate, '!') !== false) {
              $worksheetReference = self::extractSheetTitle($pCoordinate, true);
  
              return $this->parent->getSheetByName($worksheetReference[0])->cellExists(strtoupper($worksheetReference[1]));
          }
  
          // Named range?
          if ((!preg_match('/^' . Calculation::CALCULATION_REGEXP_CELLREF . '$/i', $pCoordinate, $matches)) &&
              (preg_match('/^' . Calculation::CALCULATION_REGEXP_NAMEDRANGE . '$/i', $pCoordinate, $matches))) {
              $namedRange = NamedRange::resolveRange($pCoordinate, $this);
              if ($namedRange !== null) {
                  $pCoordinate = $namedRange->getRange();
                  if ($this->getHashCode() != $namedRange->getWorksheet()->getHashCode()) {
                      if (!$namedRange->getLocalOnly()) {
                          return $namedRange->getWorksheet()->cellExists($pCoordinate);
                      }
  
                      throw new Exception('Named range ' . $namedRange->getName() . ' is not accessible from within sheet ' . $this->getTitle());
                  }
              } else {
                  return false;
              }
          }
  
          // Uppercase coordinate
          $pCoordinate = strtoupper($pCoordinate);
  
          if (Coordinate::coordinateIsRange($pCoordinate)) {
              throw new Exception('Cell coordinate can not be a range of cells.');
          } elseif (strpos($pCoordinate, '$') !== false) {
              throw new Exception('Cell coordinate must not be absolute.');
          }
  
          // Cell exists?
          return $this->cellCollection->has($pCoordinate);
      }
docs: Does the cell at a specific coordinate exist?
  
  @param string $pCoordinate Coordinate of the cell eg: 'A1'
  
  @throws Exception
  
  @return bool