home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
ftp.cs.arizona.edu
/
ftp.cs.arizona.edu.tar
/
ftp.cs.arizona.edu
/
icon
/
newsgrp
/
group95c.txt
/
000067_icon-group-sender _Wed Oct 25 13:15:42 1995.msg
< prev
next >
Wrap
Internet Message Format
|
1996-01-03
|
2KB
Received: by cheltenham.cs.arizona.edu; Wed, 25 Oct 1995 08:49:21 MST
To: icon-group@cs.arizona.edu
Date: 25 Oct 1995 13:15:42 GMT
From: rtor@ansa.co.uk (Owen Rees)
Message-Id: <46ld9u$o5v@plato.ansa.co.uk>
Organization: ANSA
Sender: icon-group-request@cs.arizona.edu
References: <CHENANDRE-0910951527080001@std32044.urich.edu>, <462sdg$qqs@archangel.terraport.net>, <DGy8uI.EEy@actrix.gen.nz>
Subject: Re: what to use instead of TCL or PERL
Errors-To: icon-group-errors@cs.arizona.edu
Des Kenny (dkenny@atlantis.actrix.gen.nz) wrote:
: Are these Objects or "Components"? It is all a bit confusing.
: I have seen one definition that makes a strong distinction:
: Objects have inheritance and consequently polymorphism.
Object does not imply inheritance - see Wegner's taxonomy and his
distinction between object-based and object-oriented.
Inheritance is neither necessary nor sufficient for polymorphism. See
Cardelli and Wegner on polymorphism, and consider a subclass that
redefines everything it has inherited.
Inheritance can be used to create useful type relationships including
polymorphism but this is not an inevitable consequence of using
inheritance.
Remember that "better" and "progress" are meaningless in the absence
of a system of measurement and that "more" and "less" are just a
matter of sign convention until related to a real problem. Attempts to
compare programming languages without reference to a system of values,
or a problem to be solved, are a waste of time.
Conjecture:
for all programming languages L there exists some context and system
of values in which L is 'best'.
--
Owen Rees
<rtor@ansa.co.uk>, <URL:http://www.ansa.co.uk/Staff/rtor.html>
Information about ANSA is at <URL:http://www.ansa.co.uk/>.