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
	autolearn=unavailable autolearn_force=no version=3.4.4
Path: 
 backlog2.nntp.ams3.giganews.com!backlog2.nntp.ams2.giganews.com!backlog2.nntp.ams.giganews.com!border3.nntp.ams.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!weretis.net!feeder4.news.weretis.net!newsfeed.datemas.de!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Ada202X: Easy to use "UML private"-like components
Date: Wed, 10 Jul 2013 20:41:30 +0100
Organization: A noiseless patient Spider
Message-ID: <ly61wiw6c5.fsf@pushface.org>
References: <69246de0-4b33-4d47-b5be-a45e8c911fb0@googlegroups.com>
 <wccwqpnux8n.fsf@shell01.TheWorld.com>
 <eabcaba2-a5aa-499d-a179-917f5dde79f3@googlegroups.com>
 <lya9luwg0u.fsf@pushface.org>
 <d22ab491-8be7-48e6-9f0c-af89d976619f@googlegroups.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Injection-Info: mx05.eternal-september.org;
 posting-host="c8504a89c76ea11bda6664e6198ae3cd";
 logging-data="15697"; mail-complaints-to="abuse@eternal-september.org";
 posting-account="U2FsdGVkX1+dDQC3irnqXv4yqBAMBXwgWF+bOL1J6cs="
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (darwin)
Cancel-Lock: sha1:fXP+pQj19vK/1YyTgQ7X8/2de8g=
 sha1:oG6ghebtdEY6DglapUJKdBY8aoo=
Xref: number.nntp.dca.giganews.com comp.lang.ada:182442
Date: 2013-07-10T20:41:30+01:00
List-Id: <comp.lang.ada>

Martin <martin@thedowies.com> writes:

> That's fine for one half the equation (implementing the "private"
> using one if the techniques mentioned before) but it still leaves
> using the "private" components...that's still a mess (my description!)
> isn't it?

I was thinking that for full code gen the translator could say "this
operation in the child class is trying to access a private attribute of
the parent! No!" and report a translation error.

Clearly not possible for framework-only generators.

My ColdFrame[1] (a) declares the instance record in the private part of
the class package, regardless of what you put in the model, (b) supports
provision of «accessor» operations, and (c) implements inheritance using
its own mechanisms rather than via tagged types; so "public" attributes
are those given accessors by the modeller, all others are "private". I
could automatically generate accessors for attributes marked "public",
but I think that people should be made to work a bit to get access to
instance variables of other classes!

[1] https://sourceforge.net/projects/coldframe/