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Re: change-class and class redefinition

Moon says:

    However, this is missing the major point.  I believe that "copying the
    slots" is the wrong model of what is happening.  A slot is a conceptual
    entity, not a word of computer storage at a particular address.  No slot
    contents are being copied or changed.  Some slots are being deleted,
    some other slots are being newly created and therefore initialized, and
    the rest of the slots remain unchanged.  If a particular implementation
    happens to work by moving the representation of a slot from location
    1000 to location 1492, that's an implementation detail and not something
    the programmer should see.  At the level of abstraction that programmers
    should deal with, a slot is a slot and nothing is being copied.

I like this argument, and am now happy with the change-class, class-changed part of this.