function clear($file_name = NULL)
	{
		if ($file_name === NULL)
		$this->_config_data = array();
		else if (isset($this->_config_data[$file_name]))
		$this->_config_data[$file_name] = array();
	}
function clear($file_name = NULL)
	{
		if ($file_name === NULL)
		$this->_config_data = array();
		else if (isset($this->_config_data[$file_name]))
		$this->_config_data[$file_name] = array();
	}
function clear ( $ file_name = NULL ) { if ( $ file_name === NULL ) $ this -> _config_data = array ( ) ; else if ( isset ( $ this -> _config_data [ $ file_name ] ) ) $ this -> _config_data [ $ file_name ] = array ( ) ; }
Clear loaded config data for a certain file or all files.

@param string $file_name file to clear config data for
Clear loaded config data for a certain file or all files .