Re: Allegro and Sbcl disagree on no-primary-method behavior

Ken Tilton wrote:


Jim Newton wrote:
Does anyone know what the behavior should be if a generic function has
an around method which does NOT call call-next-method, but there is
no primary method?

It seems that sbcl calls SB-PCL::NO-PRIMARY-METHOD which normally signals an error, but allegro calls the around method

(defgeneric foo (x))
(defmethod foo :around (x) 1)
(foo 1)

This returns 1 in allegro, and errors in sbcl. Any opinions
about which is correct behavior?

This is Lisp. If I do not call X, I better not get an error about X being undefined.

my2. kt


But you did call X. You called the generic function foo.
foo is defined. The problem is that the definition is
incomplete/invalid. So this does not break the invariant
that if you do not call X then it's OK for X to be undefined.
.

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