(defmacro scase (keyform &rest clauses)
  "Variant of CASE with equality checked using STRING= instead of EQL."
  (let ((kfsym (gensym)))
    (flet ((map-clause (rest-of-clauses)
             (cond
               ((null (car rest-of-clauses))
                (error "Invalid scase clause: ~A" (car rest-of-clauses)))
               ((and (null (cdr rest-of-clauses)) ; last clause
                     (not (consp (caar rest-of-clauses)))
                     (member (caar rest-of-clauses) '(otherwise t) :test #'string=))
                (cons t (cdar rest-of-clauses)))
               (t (let* ((clause (car rest-of-clauses))
                         (keys (car clause))
                         (body (cdr clause)))
                    (if (consp keys)
                        (cons `(member ,kfsym ',keys :test #'string=) body)
                        (cons `(string= ,kfsym ,keys) body)))))))
      `(let ((,kfsym ,keyform))
         ,(cons 'cond (maplist #'map-clause clauses))))))