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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Ada is getting more popular!
Date: Sun, 31 Oct 2010 11:06:56 -0700
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Date: 2010-10-31T11:06:56-07:00
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On 10/31/2010 03:38 AM, J-P. Rosen wrote:
>
> FWIW, here are my criteria for using inheritance:
> 1) you have several types, that are too different to be modelled as
> variations of a single type (use discriminated types otherwise);
> 2) however, these types have some common logical properties, with
> different implementations
> 3) you have to maintain an heterogenous container of these various types
> 4) you want to call the common operations on all objects in the container

FWIW, here is my criterion for using inheritance:

1. You need finalization.

-- 
Jeff Carter
"Why, the Mayflower was full of Fireflies, and a few
horseflies, too. The Fireflies were on the upper deck,
and the horseflies were on the Fireflies."
Duck Soup
95