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Making (CLASS-OF <class>) be EQ to <class>

    Date: Sat, 29 Sep 1990 00:26 EDT
    From: Jon L White <jonl@lucid.com>

    re: The invokable functionality should have been made a function in its 
	own right, and the body of the method should have been a call to that 
	. . . 
	The "problem" with what I say here is that the modularity has to be 
	worked out in advance.  I wouldn't allow people to reach inside an 
	existing program and, without changing the source code of that program, 
	pull out some functionality that they want, but which was not packaged 
	into a function by the author of that program.  

    Well that's precisely the "rub".  The object-oriented approach is that
    Programmer A's interface, which includes a listing of the methods and
    their signatures, should be usable by programmer B without having to
    delve into the source code (as I ultimately wound up doing for Kim!)

    However, the unit of functionality needed by this very temporary patch 
    was the effective method for specializers <C1, C2, ...>; and by all that
    is holy in CLOS and OO languages in general, that cannot be packaged
    out into a function by any of the various method's authors.

Not so, it can be packaged into a generic function.

    This is not the first time such a need was perceived.  Last summer 
    (of 1989) some guy from a European research center was starting to port 
    an application from their own home-grown Object-Oriented system into 
    Lucid's CLOS, and found a low-frequency place where APPLY-METHOD was 
    just the cat's meow.  Although I very much dislike the word COMPUTE in 
    COMPUTE-EFFECTIVE-METHOD  (I would prefer something like FIND, or GET, or 
    whatever ... but who cares),  it would seem that these two might go 
    hand-in-hand towards satisfying this perceived need for the very 
    ocasional "delegation."

I certainly believe that this is a perceived need.  I show no sign of ever
being convinced that it is a real need, i.e. that there is no other reasonable
way to get the job done.