Re: Possible Ada deficiency?

[Robert A Duff <bobduff@shell01.TheWorld.com>]

danmcleran@hotmail.com writes:

> That's exactly right. I would propose adding a new keyword,
> 'concealed', to allow a package writer to hide certain areas from all
> child packages.

OK, but you haven't explained why you prefer that to the idea I
proposed: allow the person who writes a package to specify the names of
all children.  That seems pretty simple.  And if you have that complete
list, you can track down all the relevant code and control it.  You
can't add new "evil" children later (without modifying the parent).

There's not really much point in a child package that *can't* see the
parent's private part.  Such a child could just as well be declared at
the same level as the parent.  So if you want some 'concealed' stuff,
the simplest thing would be to declare that this package has no
children.

Your 'concealed' idea could work, but it seems to add a lot of
complexity (to a language that already has too-complex visibility
rules).

(Of course, as Jeff Carter pointed out, none of these changes are likely
to make it into a future version of Ada.  Certainly not Ada 2005 -- the
new feature set is pretty much cast in stone at this point.)

Does it bother you that subunits can access stuff in the parent *body*?

- Bob