595       Hedr : constant QR_Ptr := To_QR_Ptr (Header);  constant
596       Next : constant QR_Ptr := Hedr.Forward;
603       Itm.Backward := Hedr;
604       Hedr.Forward := Itm;
626       Hedr : constant QR_Ptr := To_QR_Ptr (Header);  constant
627       Next : constant QR_Ptr := Hedr.Forward;
638          Hedr.Forward := To_QR_Ptr (Item).Forward;
640          if Hedr.Forward = null then
644             Hedr.Forward.Backward := Hedr;
661       Hedr : constant QR_Ptr := To_QR_Ptr (Header);  constant
662       Prev : constant QR_Ptr := Hedr.Backward;
669       Itm.Forward   := Hedr;
670       Hedr.Backward := Itm;
692       Hedr : constant QR_Ptr := To_QR_Ptr (Header);  constant
693       Prev : constant QR_Ptr := Hedr.Backward;
704          Hedr.Backward := To_QR_Ptr (Item).Backward;
706          if Hedr.Backward = null then
710             Hedr.Backward.Forward := Hedr;