Completion error

["Dominic D'Apice" <dapiced@sympatico.ca>]

Hi , what means this :

services.ads: Error: line 7 col 6 LRM:3.10.1(3), Completion required for
incomplete type 'reservation', Continuing 

I declare this :


ADS :
-------------------------------------------
type reservation;
type louer is access reservation;


ADB :
-------------------------------------------
type reservation is record
       num       : natural := 0;

       plancher  : integer := 20;
       plafond   : integer := 20;
       classe    : auto := econo;
       nomclient : string(1..256);
end record;


type tete_liste_louer is record
	 premier  : louer   := null;
	 dernier  : louer   := null;
	 longueur : natural := 0;
end record;




thanks