Re: Question about Finalization Control and reference counting

[Jeffrey Carter <jeffrey.carter@boeing.com>]

Adjust only applies to a controlled type, so you need to put your access
value inside a controlled type:

type Node;

type Node_Ptr is access all Node;

type Node is new [Limited_]Controlled with record
   Prev  : Node_Ptr;
   Data  : Whatever;
   Count : Natural := 0;
   Next  : Node_Ptr;
end record;

procedure Adjust (Object : in out Node);

procedure Finalize (Object : in out Node);

For a doubly linked list like this, you probably don't need a reference
count or Adjust. See the PragmAda Reusable Components
(PragmARC.List_Unbounded_Unprotected) for just such a list.