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From: watt@eleazar.dartmouth.edu (Gill Watt)
Newsgroups: comp.sys.mac.programmer
Subject: Re: TCL limitations question (long but worth it)...
Summary: see subj
Keywords: TCL, OOPS, CColorWindow
Message-ID: <1991Jun6.173015.17804@dartvax.dartmouth.edu>
Date: 6 Jun 91 17:30:15 GMT
Sender: news@dartvax.dartmouth.edu (The News Manager)
Distribution: comp
Organization: Dartmouth College, Hanover, NH
Lines: 33

Thanks to everyone who sent me advice about the Think Class 
Libraries.  

Yes, the problems can be worked around by casting the
CColorWindow object to a CWindow before assigning it to 
the CDirector's *itsWindow.  As follows:

	itsWindow = (CWindow *) new ( CColorWindow );


I have also found this technique to be helpful in other places
where I would like to enhance the functionality of the 
pre-existing classes without disturbing them.  

After initializing, I just cast my objects into their superclass 
for passing around the class library and whenever I require the 
additional methods, I recast them back into my own subclass.

Summary:

It's cool, it's powerful, and I can't help but think that it is
a dangerous kludge.  Why can't we have OOP for the mac without
a spiders web of interdependencies between classes?  


Thanks again.

-Gill
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Gill Watt (watt@eleazar.dartmouth.edu)
Thayer School of Engineering, Dartmouth College, Hanover, NH  03755
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