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From: gat@forsight.jpl.nasa.gov (Erann Gat)
Newsgroups: comp.lang.lisp
Subject: Re: (setf (values ...
Message-ID: <1991Jun13.232739.24568@elroy.jpl.nasa.gov>
Date: 13 Jun 91 23:27:39 GMT
References: <1991Jun13.204847.5625@jpl-devvax.jpl.nasa.gov>
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Organization: Jet Propulsion Laboratory
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In article <1991Jun13.204847.5625@jpl-devvax.jpl.nasa.gov> charest@AI-Cyclops.JPL.NASA.GOV writes:
>Anyone out there have CL code for a setf method for values as mentioned on page 129 of CLtL2? The code should handle the case wherein any of the sub-forms of values can themselves have setf methods. Thanks in advance.

Well, if you really must do such a hideous thing:

(defmacro setf-values (&rest args)
  (let ( (locations (butlast args))
         (form (car (last args))) )
    (let ( (temps (mapcar #'(lambda (s) (gensym "TEMP")) locations)) )
      `(multiple-value-bind ,temps ,form
         ,@(mapcar #'(lambda (loc new-loc) `(setf ,loc ,new-loc))
                   locations temps)))))

(defsetf values setf-values)

E.