Re: A simple ADA puzzle (I haven't the answer)

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

On Wed, 23 Jun 2004 16:37:01 -0500, Randy Brukardt wrote:

> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
> news:2i5dd0lu0i3a8bokfh7916r4j67g42ri4o@4ax.com...
> ...
>>>As I have said, it's extremely simple. Automatic variables are invisible.
>>
>> Huh, how is it better than Ada's limitation on tagged types?
> 
> The only limitation on tagged types in Ada 2005 is that you can't extend a
> formal type in a generic body. See AI-344, approved in Palma de Mallorca.
> (There are accessibility checks if you try pass an object of a nested type
> outwards.)

But I will be still able to allocate it, return a class-wide pointer and
then to dispatch to an out-of-scope subroutine. It seems that some
additional overhead will be needed to catch that.

BTW, there could be alternatives to accessibility checks, when overhead is
accepted. For example, one could forcibly upcast objects if their type goes
out of scope.

> So what are you talking about??

(:-))

--
Regards,
Dmitry A. Kazakov
www.dmitry-kazakov.de