Re: How to pass around access types to interfaces?

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

On Sat, 25 Oct 2008 18:15:09 -0400, Robert A Duff wrote:

> "Martin Krischik" <krischik@users.sourceforge.net> writes:
> 
>> Am 24.10.2008, 13:45 Uhr, schrieb Sven <sven.weidauer@gmail.com>:
>>
>>>   type My_Interface_Access is access all My_Interface'Class;
>>
>> Do you realy need an access type? Read:
>>
>> http://en.wikibooks.org/wiki/Ada_Programming/Object_Orientation#The_class-wide_type
>>
>> If so, does it need to be an access all? Read:
> 
> In my experience, access-to-class-wide types almost always need to have
> "all", because you often want to convert from access-to-T2 up to
> access-to-T1'Class (where T2 is a descendant of T1).

It would be nice if that were finally fixed! [*]

But, in general it is better to use only access to class-wide. So the cases
where access to T2 is converted to access to T1 are suspicious to me. When
that happens I readily use Unchecked_Conversion, since it is already
broken.

--------
*  Similar issue: there is no good way to obtain a pool-specific access
type from Finalize.

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