anchor.diff:  type
    TBlkNavVolba = (none = 0, VC = 1, PC = 2, NC = 3, PP = 4);
    TBlkNavOutputType = (scom = 0, binary = 1);
  + TBlkNavSymbol = (unknown = -1, hlavni = 0, seradovaci = 1);
   
    ENoEvents = class(Exception);
   
  
positive.code: var Blk:TBlk;
      oblr:TOR;
  begin
   if (Self.NavRel.SymbolType = 1) then Exit;
   if ((SenderOR as TOR).stack.volba = PV) then
     if ((Self.Navest > 0) or (JCDb.FindJC(Self.GlobalSettings.id, false) > -1)) then Exit;
  
  
negative.code: 
   // vlastnosti navestidla ziskane ze souboru .spnl (od reliefu, resp. z Mergeru)
   TBlkNavRel = record
    SymbolType:TBlkNavSymbol;                      // typ navestidla
    UsekID:Integer;                                // ID useku pred navestidlem
    smer:THVStanoviste;                            // smer navetidla (lichy X sudy)
   end;
  