Re: Possible Ada deficiency?

[danmcleran@hotmail.com]

>But if you have a package X.Y that does not want to
>access private-X stuff, then why do you want it to be a child in the
>first place?

That's not the point. If I am writing a package, I want to be able to
hide certain stuff from all future child packages. I may be the one
writing the child package, I may not be. The way I'm thinking in this
discussion is I am not the one writing the child package. So, that
being said, I want to have a way to hide certain implementation details
from all future child packages, written by whomever.

The private area would remain as-is, with child packages having full
visibility there. The 'concealed' area is an area that I do not want
child packages messing with. I would only put things, (mostly type(s)),
in the 'concealed' area that I want fully encapsulated from the outside
world, including child packages. This would force a child package to
use the public or private interface of the parent package for types
declared 'concealed'.

>In my suggested solution, X could declare "I have no children", and
then
>Y would have to be *not* a child of X.

I would like a variation of this idea. If one could specify that a
package could not have child packages, then the compiler could prevent
someone from even compiling X.Y. It would be nice to prevent future
developers from writing child packages if you don't want them to.

>But obviously it doesn't *need*
>to be a child of X, since it does not access private-X stuff.

That's not what I'm saying. I would not propose re-defining private. I
would propose the addition of 'concealed'.