Re: What would you like in Ada202X?

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

On Wed, 25 Apr 2012 21:08:06 -0500, Randy Brukardt wrote:

> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message 
> news:mdgi0fhwon01$.18b871w98pjl6.dlg@40tude.net...
> ...
>> There is no means to flatten P making declarations of Q be directly 
>> visible
>> for clients of P. E.g. something like
>>
>>   package P is
>>      package Q is new Foo (...);
>>      use all Q; -- Make things from Q declared directly in P
>>   end P;
> 
> We tried to do this for Ada 2012; we made heroic efforts to do so. The 
> problem is, this feature is a massive potential maintenance problem which 
> destroys most of the Ada concepts of visibility and maintainablity. (It's 
> all of the mistakes of package "use" multiplied a hundred-fold.)
> 
> The biggest problem comes when there is a conflict between things declared 
> in P and things declared in Q. Resolving that proved impossible without 
> introducing major headaches.

Certainly there must be a generic mechanism for handling this. Because the
same issue arises with MI.

Probably something really revolutionary is needed here, something like
introduction of T'Class was, which resolved all OO mess just per finger
snap.

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