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Fwd: Returned mail: User unknown
- To: mop.parc@xerox.com
- Subject: Fwd: Returned mail: User unknown
- From: Danny Bobrow <bobrow@parc.xerox.com>
- Date: Thu, 1 Nov 1990 10:10:18 PST
- References: <9011011750.AA01995@nero.parc.xerox.com>
Excerpts from mail: 30-Oct-90 mop questions davis@ilog.ilog.fr (3091)
> For instance, in section 3.5 there is a
> discussion of the difference between making SLOT-VALUE generic and
> using SLOT-VALUE-USING-CLASS. However, there is no explanation of why
> the CLOS MOP chose the latter approach, or of other alternatives for
> the slot access protocol.
Gregor and Jim have answered many of the direct questions. I thought I
would take a crack at this one. In Jim's answer, he talks about the
PERSISTENT-OBJECT example, how the metaclass can be distributed over
many disparate parts of the class space not connected bhas a different
distribution than an inheritance hierarchy. On the other hand, in many
examples, an inheritance hierarchy provides exactly the right handle for
a change in how SLOT-VALUE should work. The argument for using
SLOT-VALUE-USING-CLASS is therefore that both options are available
since its arguments are <class-of-object object slot>.
Cheers
danny