🚀 go-pugleaf

The choices:

 #1 -- each subclass has its own copy of its parent's class variables
 
 #2 -- all subclasses share a single copy of their parent's class variables

In article <1990Oct15.185718.8342@svc.portal.com> moose@svc.portal.com writes:
>I think this arguement is beginning to get silly.  If you do #2, you can 
>always do #1 by adding a new variable and overridding all methods that affect
>the variable in question.  If you do #1, there is no way to do #2.  
>Therefore, #2 should be done.
>Michael Rutman

     Hmmm.  I too thought the argument was silly, but I reached the opposite
conclusion.  I thought: #2 can be perfectly simulated with global (or static)
variables, while #1 gives some new functionality.  I already gave an example in
a previous post: #2 allows an event handler to be associated with each subclass
of View, just by declaring a class variable "eventHandler" in the View class
(and presumably defining some factory methods in View which reference
"eventHandler").  

     As I read Mr. Rutman's reasoning, given choice #2, all I'd have to do to
associate an event handler with every subclass of View is declare a variable
(class or static) in EVERY subclass, and provide appropriate methods in EVERY
subclass.  Yeech.  Note that I'd likely be repeating the same code in every
subclass - this seems contrary to the object-oriented paradigm, in which
inheritance is supposed to be used to avoid such of repetition of code.  This
problem doesn't come up with class variables of kind #1.    

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