anchor.diff:      | roa_common
     )
   ;
  -
   
   rof_export
   :
  
positive.code:    PREFERENCE preference = DEC
  ;
  
  roa_route
  :
    ROUTE
    (
      prefix = IP_PREFIX
      | prefix6 = IPV6_PREFIX
    )
    roa_common
  ;
  
  roa_tag
  :
     TAG tag = DEC
  
negative.code: :
     STATION_PORT DEC
  ;
  
  roa_route
  :
    ROUTE
  