anchor.diff:  
       WebInterface ${if cfg.webInterface then "Yes" else "No"}
   
  +    LogLevel ${cfg.logLevel}
  +
       ${cfg.extraConf}
     '';
   
  
positive.code:         '';
        };
  
        extraFilesConf = mkOption {
          type = types.lines;
          default = "";
  
negative.code:         example =
            ''
              BrowsePoll cups.example.com
              MaxCopies 42
            '';
          description = ''
            Extra contents of the configuration file of the CUPS daemon
  