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=0.2 required=5.0 tests=BAYES_00,INVALID_MSGID,
	REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: f43e6,9a0ff0bffdf63657
X-Google-Attributes: gidf43e6,public
X-Google-Thread: fac41,9a0ff0bffdf63657
X-Google-Attributes: gidfac41,public
X-Google-Thread: 1108a1,9a0ff0bffdf63657
X-Google-Attributes: gid1108a1,public
X-Google-Thread: 103376,4b06f8f15f01a568
X-Google-Attributes: gid103376,public
From: Loryn Jenkins <loryn@s054.aone.net.au>
Subject: Re: Module size (was Re: Software landmines)
Date: 1998/09/06
Message-ID: <35F1B435.403AE1AC@s054.aone.net.au>#1/1
X-Deja-AN: 388255928
Content-Transfer-Encoding: 7bit
References: <6snlos$bh6$1@hirame.wwa.com> <904912650snz@nezumi.demon.co.uk>
 <35EFFB78.21BBBED6@ksc.nasa.gov> <6spfvf$nun$1@hirame.wwa.com>
 <6spojo$8ir$1@uuneo.neosoft.com> <35f58f68.94311132@news.erols.com>
 <35F0BC05.61919244@s054.aone.net.au> <6srhl8$spv$1@hirame.wwa.com>
X-Priority: 3 (Normal)
Content-Type: text/plain; charset=us-ascii
X-Trace: news.mel.aone.net.au 905032803 12810 203.102.238.34 (5 Sep 1998
 22:00:03 GMT)
Organization: TekRite Pty Ltd
Mime-Version: 1.0
Reply-To: loryn@acm.org
NNTP-Posting-Date: 5 Sep 1998 22:00:03 GMT
Newsgroups: comp.lang.eiffel,comp.object,comp.software-eng,comp.lang.ada
Date: 1998-09-05T22:00:03+00:00
List-Id: <comp.lang.ada>

> class Shape
> {
>   public:
>     virtual void Draw() = 0;  // Draw shape on screen.
> }
> 
> class Pump
> {
>   public:
>     virtual void Draw() = 0; // draw water from the pump.
> };
> 
> Here are two classes that appear to have the same interface.


But they don't have the same interface. It is just that your formalism
doesn't have the power to describe the semantics. Were this written in
Eiffel, you would find the postconditions and invariant, and possibly
the preconditions, would differ.

Thus the interfaces are quite different.

Loryn Jenkins