From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on
	ip-172-31-74-118.ec2.internal
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=3.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.5-pre1
Path: eternal-september.org!reader02.eternal-september.org!aioe.org!pBWEO6hi52oGFheO/GY5ag.user.gioia.aioe.org.POSTED!not-for-mail
From: Stephen Leake <stephen_leake@stephe-leake.org>
Newsgroups: comp.lang.ada
Subject: Re: Simple example on interfaces
Date: Mon, 25 Jan 2021 11:05:24 -0800
Organization: Aioe.org NNTP Server
Message-ID: <865z3k7s7f.fsf@stephe-leake.org>
References: <f44498d1-8675-44b2-af1e-3937dcbc7a1fn@googlegroups.com>
NNTP-Posting-Host: pBWEO6hi52oGFheO/GY5ag.user.gioia.aioe.org
Mime-Version: 1.0
Content-Type: text/plain
X-Complaints-To: abuse@aioe.org
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (windows-nt)
X-Notice: Filtered by postfilter v. 0.9.2
Cancel-Lock: sha1:budy4OIM99R30m+Unp/NEZNx24A=
Xref: reader02.eternal-september.org comp.lang.ada:61198
List-Id: <comp.lang.ada>

Mario Blunk <marioblunk.alere@gmail.com> writes:

> I'm trying to solve a problem of multiple inheritance. It seems to me
> that an interface could be the solution although the interface is
> still a mystery for me.
>
> This is the example code:
>
https://github.com/Blunk-electronic/ada_training/blob/master/src/interfaces_1/interfaces_1.adb

An interface type cannot declare any data: see
http://www.ada-auth.org/standards/2xrm/html/RM-3-9-4.html

So type_c can be:

    type type_C is interface;

and you can define subprograms for type_C, but not data.

-- 
-- Stephe