Re: Possible Ada deficiency?

["Randy Brukardt" <randy@rrsoftware.com>]

<danmcleran@hotmail.com> wrote in message
news:1104622090.271236.286730@c13g2000cwb.googlegroups.com...
...
> In my example, notice that the derived type in the child package can
> change the private area, whereas the derived type in the non-child
> package cannot.

Right, that's the whole idea. You don't want to be declaring child packages
willy-nilly. You only do it when you want access to the private part.

About the only language change I could imagine making sense would be a
pragma No_Children. (The visibility and usage costs of a third kind of
declaration are too much.) But I suspect that most of the time, someone
would find they had to remove the pragma for one reason or another.

(Another idea explored very briefly was "separate" private types:
    type P is separate private;
 where the full declaration was given in the body. That wasn't seriously
considered, because Ada compilers take full advantage of the fact that the
size of types are fully known by the end of the package specification. To
change that would be a major disruption in the implementations, and the gain
wasn't considered worth it.)

                            Randy.