[comp.lang.clos] Why do SLOT-{UNBOUND,NOT-FOUND} take class argument?

barmar@think (Barry Margolin) (12/05/90)

Why do the SLOT-UNBOUND and SLOT-NOT-FOUND generic functions take the class
of the object as an argument?  They already take the object as an argument,
so class-specific behavior can be done by specializing on the object's
type.  These functions aren't part of the meta-object protocol, so why
should they need to be able to specialize on the metaclass?  Wouldn't it
have been more appropriate to have done this in the same way as SLOT-VALUE:
by defining SLOT-{UNBOUND,NOT-FOUND}-USING-CLASS meta-object g.f.'s that
take a class argument?
--
Barry Margolin, Thinking Machines Corp.

barmar@think.com
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