anchor.diff:      | K_LOGIN '=' b=BOOLEAN { opts.can_login = convert_boolean_literal($b.text); }
       ;
   
  +// Introduce a more natural syntax (SERVICE LEVEL), but still allow
  +// the original one (SERVICE_LEVEL)
  +serviceLevel
  +    : K_SERVICE_LEVEL | ( K_SERVICE K_LEVEL )
  +    ;
  +serviceLevels
  +    : K_SERVICE_LEVELS | ( K_SERVICE K_LEVELS )
  +    ;
   /**
    * CREATE SERVICE_LEVEL [IF NOT EXISTS] <service_level_name> [WITH <param> = <value>]
    */
  
positive.code: K_SERVICE_LEVELS: S E R V I C E '_' L E V E L S;
  K_ATTACHED: A T T A C H E D;
  K_FOR: F O R;
  
  K_SCYLLA_TIMEUUID_LIST_INDEX: S C Y L L A '_' T I M E U U I D '_' L I S T '_' I N D E X;
  K_SCYLLA_COUNTER_SHARD_LIST: S C Y L L A '_' C O U N T E R '_' S H A R D '_' L I S T; 
  
negative.code: detachServiceLevelStatement returns [std::unique_ptr<detach_service_level_statement> stmt]
      @init {
      }
      : K_DETACH serviceLevel K_FROM role_name=serviceLevelOrRoleName
        { $stmt = std::make_unique<detach_service_level_statement>(role_name); }
      ;
  
  