smart pointer dangerous (no -> operator)

[Oliver Kowalke <oliver.kowalke@gmx.de>]

Hello,
Ada doesn't support the dereference operator -> as C++.

So Ada provides only two ways to access the managed object?

- returning it via value : function Get(Pointer : Smart_Pointer) return
Object;

- returning it via access type : function Get(Pointer : Smart_Pointer)
return Access_Object;

- returning a proxy which implements the functions applicable to the managed
object

In the first case I can not manipulate the state of the managed object
(setting some internal data).
The second case is dangerous because the ownership 'constraint' can be
violated -> other code can call Unchecked_Delete on the returned access
type or assign it to another one.

How can case three be implemented in Ada if the smart ponter package is
generic?


regards,
Oliver