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Re: OPERATION NOT HANDLED
> ...For example, consider a procedure (or operation) that would behave
>like WHERE-DEFINED, except it would return NIL (rather than breaking) if the
>object didn't handle the WHERE-DEFINED operation (e.g., tables and
I think the default body of DEFINE-OPERATION will handle this for you, i.e.,
(define-operation (where-defined foo) nil)
will cause NIL to be returned if WHERE-DEFINED isn't defined.
Scott R. Turner
UCLA Computer Science "Are we controlled by secret forces?"