When removing the variable from the superclass, "collection" got 
transferred as a binding to Undeclared which makes it behave like a 
class variable. Therefore, superclass and subclass have different 
"meanings" when you refer to the name collection (superclass thinks it's 
a "class var", subclass thinks it's an iVar).

Cheers,
   - Andreas

Josh Gargus wrote:
> I have created a changeset in which a class is created with an iVar,  
> methods added that reference that iVar, and finally the class  
> definition is changed to remove the iVar.  Newly created instances of  
> the class behave as though the iVar is still present.
> 
> Furthermore, when I add a new subclass that has an iVar of the same  
> name, the class compiles OK (if the superclass had explicitly defined  
> the iVar, I would not have been able to define it in the subclass).   
> However, different slots are being accessed by superclass methods and  
> subclass methods.  In the following code (file in the attached  
> changeset first):
> 
> inst := ClassThatUsedToHaveAVariable new.
> inst add: 'string'.
> inst contents.
> 
> subInst := ClassThatUsedToHaveAVariableSubclass new.
> subInst add: 'string2'.
> subInst subAdd: 'string3'.
> subInst contents.
> subInst subContents.
> 
> 
> 'subInst contents' and 'subInst subContents' do not give the same  
> result.  However, if the 'collection' variable is deleted from the  
> subclass definition, they do answer the same result.
> 
> What exactly are the semantics here?  It seems like this could  possibly 
> cause some problems.
> 
> Thanks,
> Josh
> 
> 
>  
>  
> 
> 
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> 
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