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(define-setf-expander values-subseq (sequence start end &environment env)
           (check-type start integer)
           (check-type end integer)
           (multiple-value-bind (temps values newval setter getter)
               (get-setf-expansion sequence env)
             (declare (ignore setter newval))
             (let* ((stemp (gensym "SEQUENCE"))
                    (size (- end start))
                    (_ (check-type size (integer 1)))
                    (vtemps (loop repeat size collect (gensym "ELEMENT"))))
               (declare (ignore _))
               (values (append temps (list stemp))
                       (append values (list getter))
                       vtemps
                       `(values ,@(loop for vtemp in vtemps
                                        for i from start
                                        collect `(setf (elt ,stemp ,i) ,vtemp)))
                       `(values ,@(loop for i from start below end
                                        collect `(elt ,stemp ,i)))))))