original_string: private function driverClass()
      {
          if (null == $this->driverClass) {
              $this->driverClass = $this->determineDriver($this->file);
          }
          return $this->driverClass;
      }
code: private function driverClass()
      {
          if (null == $this->driverClass) {
              $this->driverClass = $this->determineDriver($this->file);
          }
          return $this->driverClass;
      }
code_tokens: private function driverClass ( ) { if ( null == $ this -> driverClass ) { $ this -> driverClass = $ this -> determineDriver ( $ this -> file ) ; } return $ this -> driverClass ; }
docstring: Returns the driver class to be initialized
  
  @return mixed|null|string
docstring_tokens: Returns the driver class to be initialized