code: public function delete($pCoord)
      {
          if ($pCoord === $this->currentCoordinate && $this->currentCell !== null) {
              $this->currentCell->detach();
              $this->currentCoordinate = null;
              $this->currentCell = null;
              $this->currentCellIsDirty = false;
          }
  
          unset($this->index[$pCoord]);
  
          // Delete the entry from cache
          $this->cache->delete($this->cachePrefix . $pCoord);
      }
docs: Delete a cell in cache identified by coordinate.
  
  @param string $pCoord Coordinate of the cell to delete