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=-0.4 required=5.0 tests=AC_FROM_MANY_DOTS,BAYES_00
	autolearn=no autolearn_force=no version=3.4.4
X-Google-Thread: 103376,ffc9e2fe760c58fd
X-Google-Attributes: gid103376,public
X-Google-Language: ENGLISH,ASCII-7-bit
Path: 
 g2news1.google.com!news3.google.com!news4.google.com!news.glorb.com!newsfeed.cw.net!cw.net!news-FFM2.ecrc.de!newsfeed01.sul.t-online.de!t-online.de!news.tiscali.de!not-for-mail
From: Wilhelm Spickermann <zhopi.20.unbenutzbar@spamgourmet.com>
Newsgroups: comp.lang.ada
Subject: Re: Records that could be arrays
Date: Thu, 23 Feb 2006 15:29:12 +0100
Organization: Tiscali Germany Usenet
Message-ID: <dtkgrp$1fkc$1@ulysses.news.tiscali.de>
References: <WBaLf.18619$HU.13588@trnddc04>
 <dtjktp$1avk$1@ulysses.news.tiscali.de> <VEiLf.19642$HU.5327@trnddc04>
NNTP-Posting-Host: p83.129.15.106.tisdip.tiscali.de
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7Bit
X-Trace: ulysses.news.tiscali.de 1140704953 48780 83.129.15.106 (23 Feb 2006
 14:29:13 GMT)
X-Complaints-To: abuse@tiscali.de
NNTP-Posting-Date: Thu, 23 Feb 2006 14:29:13 +0000 (UTC)
User-Agent: KNode/0.8.0
Xref: g2news1.google.com comp.lang.ada:3106
Date: 2006-02-23T15:29:12+01:00
List-Id: <comp.lang.ada>

Hi,

Justin Gombos wrote:

> On 2006-02-23, Wilhelm Spickermann
> <zulo.20.unbenutzbar@spamgourmet.com> wrote:
>>
>> I think it depends on the meaning of "type". The three
>> floating point numbers in a polar coordinate system are of
>> three different _kinds_ and should be put into a record and
>> not into an array -- even if they have the same _type_.
> 
> Why?
> 

These coordinates are of a different kind as they are used
differently -- all geometric formulas handle them differently.
So it is just a coincidence if they are of the same type and so
I wouldn't draw design decisions from the type alone. 

This becomes also visible in the missing loop statements in
typical polar coordinate operations. And it would be rather
unusual for an array to have a special equality definition while
it is rather normal for a record (phi is "dont care" when theta
is zero -- or AFAIK the other way round in North America).

Wilhelm