abstract variables proposalQQ
Ramon Leon
ramon.leon at allresnet.com
Wed Nov 29 18:00:33 UTC 2006
> One of my fustrations in using Smalltalk is that I may have a
> subclass B with a number
> of subclasses, say C,D,E,F and such that some of the
> subclasses, say C and D,
> need to access an instance variable, say b, but the
> remainding classes, say E and F, do not need to access
> variable b. In this situation I have two basic options:
>
Would you mind stating a real world example of this scenario? I ask because
I have the feeling the problem is more related to design of the class
hierarchy than to anything wrong with Smalltalk. If E and F don't need all
the instance variables of B, then they simply shouldn't subclass B.
Subclasses should only extend the behavior of a parent class, not restrict
or change it, so I'm curious on seeing a real example of this issue.
Ramon Leon
http://onsmalltalk.com
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