anchor.diff:     | apply_groups_if_stanza
   ;
   
  -apply_groups_if_stanza // TODO: FIX!
  -
  -:
  -   apply_groups_stanza
  -;
  -
  -disable_if_stanza
  -:
  -   DISABLE SEMICOLON
  -;
  -
  -enable_if_stanza
  -:
  -   ENABLE SEMICOLON
  -;
  -
  -unit_if_stanza
  -:
  -   UNIT
  -   (
  -      num = DEC
  -      | UNIT_WILDCARD
  -   )
  -   (
  -      SEMICOLON
  -      |
  -      (
  -         OPEN_BRACE
  -         (
  -            u_if_stanza
  -            | inactive_u_if_stanza
  -         )+ CLOSE_BRACE
  -      )
  -   )
  +if_stanza_list
  +:
  +   (
  +      if_stanza
  +      | inactive_if_stanza
  +   )+
  +;
  +
  +inactive_fam_u_if_stanza
  +:
  +   INACTIVE COLON fam_u_if_stanza
  +;
  +
  +inactive_if_stanza
  +:
  +   INACTIVE COLON if_stanza
  +;
  +
  +inactive_interface_stanza
  +:
  +   INACTIVE COLON interface_stanza
  +;
  +
  +inactive_u_if_stanza
  +:
  +   INACTIVE COLON u_if_stanza
  +;
  +
  +input_vlan_map_u_if_stanza // TODO [Ask Ari]: probably not supposed to ignore this
  +
  +:
  +   INPUT_VLAN_MAP ignored_substanza
  +;
  +
  +interface_mode_fam_u_if_stanza // TODO [P0]: should not be ignored
  +
  +:
  +   INTERFACE_MODE ACCESS SEMICOLON
  +;
  +
  +interface_stanza
  +:
  +   name = VARIABLE? OPEN_BRACE if_stanza_list CLOSE_BRACE
  +;
  +
  +interfaces_stanza
  +:
  +   INTERFACES OPEN_BRACE
  +   (
  +      interface_stanza
  +      | inactive_interface_stanza
  +   )+ CLOSE_BRACE
  +;
  +
  +link_mode_if_stanza
  +:
  +   LINK_MODE VARIABLE SEMICOLON
  +;
  +
  +mac_if_stanza
  +:
  +// TODO [p1]: should be MAC_ADDRESS, solve with lexer modes in antlr 4
  +   x = MAC y = MAC_ADDRESS SEMICOLON
  +;
  +
  +mtu_fam_u_if_stanza
  +:
  +   mtu_common_stanza
  +;
  +
  +mtu_if_stanza
  +:
  +   mstr = mtu_common_stanza
  +;
  +
  +native_vlan_id_fam_u_if_stanza
  +:
  +   NATIVE_VLAN_ID DEC SEMICOLON
  +;
  +
  +no_neighbor_learn_fam_u_if_stanza
  +:
  +   NO_NEIGHBOR_LEARN SEMICOLON
  +;
  +
  +no_redirects_fam_u_if_stanza
  +:
  +   NO_REDIRECTS SEMICOLON
  +;
  +
  +null_fam_u_if_stanza
  +:
  +   interface_mode_fam_u_if_stanza
  +   | mtu_fam_u_if_stanza
  +   | port_mode_fam_u_if_stanza
  +   | no_redirects_fam_u_if_stanza
  +   | no_neighbor_learn_fam_u_if_stanza
  +   | policer_fam_u_if_stanza
  +   | primary_fam_u_if_stanza
  +   | rpf_check_fam_u_if_stanza
  +   | targeted_broadcast_fam_u_if_stanza
  +   | vlan_id_fam_u_if_stanza
   ;
   
   null_if_stanza
  
positive.code:    | vlan_tagging_if_stanza
  ;
  
  aggregated_ether_options_if_stanza
  :
     AGGREGATED_ETHER_OPTIONS ignored_substanza
  ;
  
  description_if_stanza
  :
     description_common_stanza
  ;
  
  encapsulation_if_stanza
  :
     encapsulation_common_stanza
  ;
  
  framing_if_stanza
  :
     FRAMING ignored_substanza
  ;
  
  flexible_vlan_tagging_if_stanza
  :
     FLEXIBLE_VLAN_TAGGING SEMICOLON
  ;
  
  gigether_options_if_stanza
  :
     GIGETHER_OPTIONS ignored_substanza
  ;
  
  link_mode_if_stanza
  :
     LINK_MODE VARIABLE SEMICOLON
  ;
  
  mac_if_stanza
  :
  // TODO [p1]: should be MAC_ADDRESS, solve with lexer modes in antlr 4
     x = MAC y = MAC_ADDRESS SEMICOLON
  ;
  
  mtu_if_stanza
  :
     mstr = mtu_common_stanza
  ;
  
  traps_if_stanza
  
negative.code:    TRAPS SEMICOLON
  ;
  
  tunnel_u_if_stanza // TODO [Ask Ari]: probably not supposed to ignore this
  
  :
     TUNNEL ignored_substanza
  ;
  
  u_if_stanza
  