Re: APQ

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

On Wed, 22 Dec 2004 17:53:14 +0100, Martin Krischik wrote:

> Dmitry A. Kazakov wrote:
> 
>> On Wed, 22 Dec 2004 11:07:44 +0100, Martin Krischik wrote:
>> 
>>> Warren W. Gay VE3WWG wrote:
>>> 
>>>> I can't imagine it making a practical difference here, but
>>>> perhaps I lack imagination on this point.
>>> 
>>>
> http://en.wikibooks.org/wiki/Programming:Ada:Types:access#access_vs._access_all
>> 
>> Pool-specific access types do not do well:
>> 
>> 1. Upcast/downcast conversions do not work. You'll need
>> Unchecked_Conversion of pointers. It is nasty and dangerous.
>> 
>> 2. '[Unchecked_]Access does not work (otherwise, (1) would be a minor
>> problem).
>> 
>> 3. Rosen's trick does not work. Very bad. Move it to Initialize? That
>> won't work either, because of 2.
>> 
>> 4. Construction/destruction is headache. Wished to insert a newly created
>> object into a list? Not from Initialize! To delete it from there upon
>> destruction? Nay!
>> 
>> 5. Access discriminants cannot be pool-specific. Converting to general
>> access to specific one is again an Unchecked_Conversion of worst kind.
>> 
>> 6. There is no way to restrict objects allocations to a definite set of
>> pools. "type X (<>) is ..." does not count.
>> 
>> In general, I think that the issue should be thoroughly reworked.
> 
> Well, ist wiki. Klick on [edit] and make your point. It OK by me - actually
> it is he hole point of wiki: incremental impovement.

Of what? Is wiki =ARG or else [edit button] = AI? (:-))

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