Object>>veryDeepCopyUsing: is a utility method.  When you have a 
complex data structure, involving several custom classes, 
veryDeepCopy on a subpart may not do what you want.  When you 
veryDeepCopy one of your objects, it does not know which instance 
variable are actually pointers back to a 'global' object, which 
should not be duplicated.  The 'parent' links in a tree are an 
example.  These can be handled by creating veryDeepInner: and 
veryDeepFixupWith:.  However, it may be easier to make a custom 
veryDeepCopy method.  In it, you create a DeepCopier, and store into 
its references dictionary with (globalObject -> globalObject).  Then 
you want to start a veryDeepCopy using that DeepCopier, and calling 
veryDeepCopyUsing: is the way to do that.

Change Set:		VeryDeepCopyU-tk
Date:			13 May 2003
Author:			Ted Kaehler

(Tested in a standard 3.6alpha)
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