I have been an object oriented programmer for nearly three hours now.
I am using Objectclass in Poplog version 14.2.
I have defined a class whose slots are continuously variable parameters.
I want to define sub-classes of this class that have non-overlapping parameter
ranges within the superclass range: think of dwarfs, people, and giants who are
defined to be apes with non-overlapping ranges of heights.
How do I specify, or enforce, constraints on the slot fillers of an instance?
If the filler for a slot exceeds the allowable parameter range can I automatically
search the inheritance hierarchy for an acceptable sub-class and return an
error instance if none is found?
Am I asking too much of object oriented programming?
(Yes, I know that another three hours of reading Steve's files and working through
Aaron's amusing teach files would probably settle the matter, but I've had enough for
one day and I could realy do with the answers before I take too many more
design decisions.)
James Anderson
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