anchor.diff:  DELETE:                                D E L E T E;
   DENY:                                  D E N Y;
   DESC:                                  D E S C;
  -DESCRIPTION:                           D E S C R I P T I O N;
   DISK:                                  D I S K;
   DISTINCT:                              D I S T I N C T;
   DISTRIBUTED:                           D I S T R I B U T E D;
  
positive.code: 
  end_conversation
      : END CONVERSATION conversation_handle=LOCAL_ID ';'?
        (WITH (ERROR '=' faliure_code=(LOCAL_ID | STRING) DESCRIPTION '=' failure_text=(LOCAL_ID | STRING))? CLEANUP? )?
      ;
  
  waitfor_conversation
  
negative.code:     ;
  
  value_method
      : (LOCAL_ID | EVENTDATA | query_method) '.value(' xquery=STRING ',' sqltype=STRING ')'
      ;
  
  query_method
  