From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM
	autolearn=unavailable autolearn_force=no version=3.4.4
X-Received: by 10.236.19.51 with SMTP id m39mr8812837yhm.31.1431639248051;
        Thu, 14 May 2015 14:34:08 -0700 (PDT)
X-Received: by 10.140.97.7 with SMTP id l7mr125225qge.0.1431639248035; Thu, 14
 May 2015 14:34:08 -0700 (PDT)
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!feeder.eternal-september.org!news.glorb.com!z60no368267qgd.1!news-out.google.com!k20ni9579qgd.0!nntp.google.com!z60no368266qgd.1!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail
Newsgroups: comp.lang.ada
Date: Thu, 14 May 2015 14:34:07 -0700 (PDT)
In-Reply-To: <mirl2d$mij$1@loke.gir.dk>
Complaints-To: groups-abuse@google.com
Injection-Info: glegroupsg2000goo.googlegroups.com;
 posting-host=80.119.168.244;
 posting-account=O3LyFwoAAACc1uh60ZcOUmAGdDmGsEcV
NNTP-Posting-Host: 80.119.168.244
References: <da4139a7-d66a-4153-a68f-7eca4c8982b0@googlegroups.com>
 <5hbl45anxasb.1jn73i00zgy2i.dlg@40tude.net> <migd9c$k9h$1@loke.gir.dk>
 <d0b830a1-19c8-462e-b1c8-a2b19e470674@googlegroups.com>
 <mirl2d$mij$1@loke.gir.dk>
User-Agent: G2/1.0
MIME-Version: 1.0
Message-ID: <835a2cf7-0e27-4759-af80-8c93dc4f5a62@googlegroups.com>
Subject: Re: Polymorphism
From: slos <new.stephane.los@gmail.com>
Injection-Date: Thu, 14 May 2015 21:34:08 +0000
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
Xref: news.eternal-september.org comp.lang.ada:25882
Date: 2015-05-14T14:34:07-07:00
List-Id: <comp.lang.ada>

Le mardi 12 mai 2015 03:29:50 UTC+2, Randy Brukardt a =E9crit=A0:
> "slos" wrote in message=20
> news:...
> Le jeudi 7 mai 2015 21:09:33 UTC+2, Randy Brukardt a =E9crit :
> ...
> > If I remember correctly, I should have verified before posting but it's=
=20
> > already
> > late, in C++ one can have protected members which can be used by friend=
s.
> > I can't see in Ada such thing like protected stuff and friends. Maybe=
=20
> > there is ?
>=20
> Ada uses child packages for that sort of functionality; to be a "friend" =
in=20
> Ada, a package has to be a child. Often, a parent and set of children is=
=20
> referred to as a "subsystem". [Private packages also can be part of a=20
> subsystem, that's where they're useful.] Unrestricted use of friends=20
> appeared to lead to madness (at a minimum, visibility madness), where=20
> dependencies go all which ways. Ada limits such dependencies to a single=
=20
> subsystem. (Generally, one wants to minimize dependences.)
>=20
> ...
> >I am quite happy with the child package solution exposed here by Simon
> >but then that has disturbed my packages hierarchy... ;-)
>=20
> Yup. There's no free lunch. ;-)
>=20
>                      Randy.

Hello Randy,

Thanks for your detailed information.
In fact, I am very happy with the solution and it ends up quite understanda=
ble, from my point of view...

Since derived objects are children of their parent class, it seems logical =
that the packages where they are defined are also children of those where t=
heir parent is.

That's only necessary if needed to access private attributes and methods bu=
t it is maybe a good idea to do so in most cases since the package hierarch=
y then mimics the objects hierarchy, isn't it ?

Best Regards,
St=E9phane
http://slo-ist.fr/ada4autom