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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Full view of a private partial view cannot be a subtype
Date: Mon, 4 Dec 2017 19:04:26 +0100
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Date: 2017-12-04T19:04:26+01:00
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On 12/03/2017 11:23 PM, Jere wrote:
> 
> Well, I think either form is a bit too polar.  I've always been taught that
> you use the tool that makes the most sense given the context.  If a type
> has an "is a" relationship, you favor extension.  But if it has a "has a"
> relationship, you favor composition.  If the situation is unique enough,
> then you do something outside the norm.

The most important thing is to create the simplest and clearest code possible. 
Tools must be judged by how well they help achieve this. Between type extension 
and composition, composition is almost always easier to read and understand.

-- 
Jeff Carter
"I would never want to belong to any club that
would have someone like me for a member."
Annie Hall
41