anchor.diff:  //-----------------------------------------------------------------
   // TCP Protocol rules.
   // (PROTOCOL = TCP)(HOST = hostname)(PORT = portnumber)
  -
   //-----------------------------------------------------------------
   tcp_protocol     : tcp_params ;
                    
  
positive.code: 
  // ---------------------------------------------------------------
  // Ok, I know this defines an IP version 4 address, but I haven't
  // got my head around the ipv6 format yet!
  // ---------------------------------------------------------------
  IP               : (DIGIT)+ DOT (DIGIT)+ DOT (DIGIT)+ DOT (DIGIT)+ ;
                   
  YES_NO           : Y E S | N O ;
                   
  
negative.code: 
  
  //-----------------------------------------------------------------
  // SPX Protocol rules.
  // (PROTOCOL = SPX)(SERVICE = spx_service_name)
  //-----------------------------------------------------------------
  spx_protocol     : spx_params ;
  
  spx_params       : spx_parameter+ ;
  
  spx_parameter    : spx_spx
                   | spx_service ;
  
  spx_spx          : L_PAREN PROTOCOL EQUAL SPX R_PAREN ;
  
  spx_service      : L_PAREN SERVICE EQUAL ID R_PAREN ;
  
  