From: James Coglan <jcoglan@...>
Date: 2008-09-17T16:25:26+09:00
Subject: Re: SuperClass and Modules

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>
> Multiple inheritance has one big problem usually denominated as "the
> diamond problem". Check this link:
> http://en.wikipedia.org/wiki/Diamond_problem.
> Ruby using single inheritance plus mixins gives almost the same
> advantages without these problems.



You cannot have multiple inheritance without the diamond problem -- that
page actually mentions how Ruby resolves method names in this case:

module A; end
module B; include A; end
module C; include A; end

class D
  include B
  include C
end

Methods will be looked up in D, C, B and A (in that order) when you call a
method on an instance of D.

--
James Coglan
http://blog.jcoglan.com
http://github.com/jcoglan

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