package Queue_Pack_Object_Base is

type Queue_Type is tagged record
      Top, Free : Marker  := Marker'First;
      Is_Empty  : Boolean := True;
      Elements  : List;
   end record;

type Element is new Positive range 1 .. 1000;

type Marker is mod Queue_Size;

type List is array (Marker) of Element;

Queue_Size : constant Positive := 10;

Queue_overflow, Queue_underflow : exception;

Queue_underflow : exception;

procedure Enqueue 
(
Item
:     Element;
Queue
: in out Queue_Type);

procedure Dequeue 
(
Item
: out Element;
Queue
: in out Queue_Type);

function Is_Empty 
(
Queue
: Queue_Type) return Boolean;

function Is_Full  
(
Queue
: Queue_Type) return Boolean;