Re: controlled type in generic package?

[Brian Rogoff <bpr@shell5.ba.best.com>]

On Fri, 9 Feb 2001, John English wrote:
> Florian Weimer wrote:
> > It's just an ordinary mixin construction.  Of course, there some
> > syntactical overhead involved, but it's straightforward.
> 
> Not hard to do, but annoying. A type declaration for the controlled
> type, a separate type declaration for the derived type with a controlled
> component added in, and if the controlled component's primitives need to
> look at any components of the original record, some magic spells involving
> access discriminants and view conversions.
> 
> This might not bother you, but it feels like acrobatics and atrocities to me.
> IMHO this is straightforward in the same sense as OOP in C is straightforward:
> "It's just an ordinary pointer-to-array-of-functions construction. Of course,
> there's some syntactical overhead involved, but it's straightforward." :-)

Maybe even worse, since the OOP in C idiom is entirely explicit, whereas 
Controlledness has some implicitness about it. 

Oh well, I agree it's annoying, but I'm not even sure it's a misfeature. Any 
better ideas on a design for finalization, assuming you can't change Ada 
dramatically? 

-- Brian