🚀 go-pugleaf

>>>>> On Tue, 3 Nov 1992 00:26:30 GMT, charest@ai-cyclops.jpl.nasa.gov (Len Charest) said:

			     .    .    .

   Len> I use the generic function CLASS-DIRECT-INSTANCES to access
   Len> the instance list.  The following :AROUND method on
   Len> CLASS-PROTOTYPE solves the problem described above.

   Len> (defmethod class-prototype :around ((class caching-class))
   Len>   (let ((prototype (call-next-method)))
   Len>     (setf (class-direct-instances class)
   Len>           (delete prototype (class-direct-instances class) :test #'eq))
   Len>     prototype))

Dear MOP gods;

Since class instance prototypes have nothing but unbound slots, perhaps
the MOP should specify that class instance prototypes be created with
allocate-instance instead of using make-instance (as Lucid has done).
Since class instance prototypes don't need the initializing power of
make-instance, make-instance could be left as a pristine, uncluttered
hook for specializing on the creation of non-prototype instances.  Any
thoughts?


                                   Eric Peterson (speaking for myself)
                                   Systems Research and Applications
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