Re: Idiom for a class and an object in Ada

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Thu, 21 Oct 2004 01:46:39 GMT, Matthew Heaney wrote:

> Jeffrey Carter <spam@spam.com> writes:

>> And this is why C++ is never a good guide to how to do things in
>> Ada. The pointer may well be needed in C++; it's not needed in Ada.
> 
> I don't understand this comment.  How else do you dynamically create
> instances of T?

Why should they be created dynamically (heap)? Heap vs. stack is a matter
of object's scope. It should have little or no impact on the design of the
type. If it has then probably because of language deficiency, as in C++,
or, yes, in Ada where there was no way to initialize limited objects. That
will be corrected soon, I hope.

For Marin's case the objects are not dynamic. So if read-only objects would
suffice, one can just use functions returning limited objects:

package Limited_Object is
   type X (<>) is limited private;
   function O1 return X; -- No pointer needed
   ...

package body Limited_Object is
   O1_Value : X;
   function O1 return X is
   begin
      return O1_Value; -- This is OK, O1_Value is never out of scope
   end O1;
   ...

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de