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From: Matthew Heaney <matthew_heaney@acm.org>
Subject: Re: Private Children
Date: 1999/06/23
Message-ID: <m3g13jeglj.fsf@mheaney.ni.net>#1/1
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Newsgroups: comp.lang.ada
Date: 1999-06-23T00:00:00+00:00
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On 23 Jun 1999 11:54, dale@cs.rmit.edu.au (Dale Stanbrough) wrote:

> Your 2nd proposal has the problem that implementation of types
> declared in P.Private_Stuff can be seen by any child packages, so you
> loose any ability to do hiding of abstractions -within- a hierachy.

But that's already the case:

  package P is

    type T is tagged private;
    ...

  private

    type T is ...;

  end P;


  package P.C1 is ...

  package P.C2 is ...


Every child (C1, C2) has access to the private part of its parent (P).
There's no such thing as "hiding within a hierarchy."

Child packages were designed not to hide visibility from within the
hierarchy.  They were designed to /deliberately/ expose the private part
to children, and to allow you to easily identify which packages have
that private knowledge.