Re: controlled types and point of instanciation

[Mehdi Saada <00120260a@gmail.com>]

By the way, I may ask something else related to pointers and this book. Does the preliminary test of this function seems ok ?

function Pointer (Value : Access_Type) return Pointer_Type is
    Object : Pointer_Type;
begin
    if Object.Pointer /= null then
       Delete_Item (Object.Pointer.Value);
    else
       Object.Pointer := new Reference_Counted_Object;
    end if;
    Object.Pointer.all := (Value => Value, Count => 1);
    return Object;
end Pointer;

That Pointer_type has no default values whatsoever, so it doesn't seems necessary to me.
its structure is
type Pointer_Type is new Ada.Finalization.Controlled with
record
     Pointer : Reference_Counted_Pointer;
end record;
and Pointer is a banal access type.
type Reference_Counted_Pointer is access Reference_Counted_Object;
type Reference_Counted_Object is
record
   Value : Access_Type; -- > from generic parameter, points at a non limited unconstrained type.
        type Access_Type is access Item_Type;
   Count : Natural;
end record;