From: Robert Klemme <bob.news@...>
Date: 2004-12-31T04:21:43+09:00
Subject: Re: Inheritance of class variables


"Eustaquio Rangel de Oliveira Jr." <eustaquiorangel@yahoo.com> schrieb im 
Newsbeitrag news:41D43A27.6070108@yahoo.com...
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> Hi!
>
> | I would probably model your example completely different, because Honda
> | and Ford are really instances of CarBuilder not really sub classes.  So
> | this is the result and suddenly we don't need class vars any more:
>
> Thanks for your example! I'm learning about Ruby and taking notes to make 
> a
> begginer's tutorial, so while the Guy example really help me to go deep
> inside the Ruby depths and think about all that stuff there (wow Guy I was
> really amazed with the concept of creating a instance variable there!),
> your example is easier for newbies (like me, also) to understand.

But please note that my point was not so much about Ruby but about OO 
modeling.  Honda, Ford and others are really instances of CarBuilder. 
That's why you just need one class.

Of course, if you had different kinds of CarBuilders with different 
capabilities (say LorryCarBuilder, SedanCarbuilder, SUVCarBuilder and 
SportsWagonCarBuilder) you would need several classes; but even then Ford 
would be an instance of LorryCarBuilder (or whatever) which normally would 
inherit CarBuilder.

> Thanks!

You're welcome!  I'm glad I could be of any help.

Regards

    robert