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=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD,
	FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!usenet.blueworldhosting.com!feeder01.blueworldhosting.com!peer01.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!post01.iad.highwinds-media.com!fx01.iad.POSTED!not-for-mail
From: Shark8 <OneWingedShark@gmail.com>
User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64;
 rv:30.0) Gecko/20100101 Thunderbird/30.0a1
MIME-Version: 1.0
Newsgroups: comp.lang.ada
Subject: Re: A bad counterintuitive behaviour of Ada about OO
References: <lrrdm1$u6n$1@speranza.aioe.org>
 <932kntuq5rrr.8sumwibqrufn.dlg@40tude.net> <lrrha0$6mh$3@speranza.aioe.org>
 <1ohy7vnbntskq$.h139ov04mlxu$.dlg@40tude.net>
 <b54d73cd-a0ad-4755-9923-f02cfa43f81d@googlegroups.com>
 <lrvf3f$sd0$1@dont-email.me> <fuhzyiqbbxi1.177yako16rvfm.dlg@40tude.net>
 <lrvn8u$cgd$1@dont-email.me> <xmabybhkwzku.189kwtirj3izb$.dlg@40tude.net>
 <lrvv95$ba$1@dont-email.me> <1lREv.450693$4n.74225@fx31.iad>
 <ls1vf5$c3a$2@dont-email.me> <mD%Ev.229884$AN6.142135@fx01.iad>
 <1oj0b4rwma99b$.1iqu11p0ea556$.dlg@40tude.net>
In-Reply-To: <1oj0b4rwma99b$.1iqu11p0ea556$.dlg@40tude.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID: <De2Fv.229885$AN6.6055@fx01.iad>
X-Complaints-To: abuse@teranews.com
NNTP-Posting-Date: Fri, 08 Aug 2014 11:10:27 UTC
Organization: TeraNews.com
Date: Fri, 08 Aug 2014 05:10:25 -0600
X-Received-Bytes: 1999
X-Received-Body-CRC: 3800517016
Xref: news.eternal-september.org comp.lang.ada:21545
Date: 2014-08-08T05:10:25-06:00
List-Id: <comp.lang.ada>

On 08-Aug-14 02:26, Dmitry A. Kazakov wrote:
> The idea that subtyping can be directly reflect substitutability is the
> root problem and the idea that the set of values could somehow define the
> type so generalization or specialization might mean something. Ada's
> subtypes suffer this as well. Both are wrong.

I don't understand this; subtypes are perfectly fine: essentially they 
are subsets over the set of values that a type may take. -- Is this to 
say they are a magic bullet? Nope.

But that certainly covers a lot of things that would otherwise make for 
sloppy and error-prone programs -- it keeps things neat, being able to 
[essentially] say parameter [or return-value] X of subprogram K is a 
subset of the values of Type T.