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From: johnson@p.cs.uiuc.edu
Newsgroups: comp.object
Subject: Re: Inheritance is NOT Delagation (
Message-ID: <135300009@p.cs.uiuc.edu>
Date: 13 Oct 89 22:28:00 GMT
References: <351@nebula.ACA.MCC.COM>
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Nf-ID: #R:nebula.ACA.MCC.COM:351:p.cs.uiuc.edu:135300009:000:542
Nf-From: p.cs.uiuc.edu!johnson    Oct 13 17:28:00 1989


>I'm not familiar with SmallTalk, 
>but I'd bet the class library is deeper than 3 in parts.  Any takers?

Object
  Controller
    MouseMenuController
      ScrollController
        ParagraphEditor
          TextController
            CodeController

However, I don't think that ScrollController should be in the hierarchy,
since I think that scrolling should be reused by components, not by
inheritance.  Moreover, it is not clear that one should count Object.
Even with this caveat, the class library is a lot deeper than 3.

Ralph Johnson