recursing-restart.lisp

(define-condition always-error (error) ())

(defun always-fail ()
  (restart-case
      (progn
        (format t "Trying...~%")
        (signal 'always-error))
    (retry ()
      (always-fail))))

(defun make-handler (&optional (retries 2))
  (lambda (condition)
    (when (typep condition 'always-error)
      (if (<= retries 0)
          (format t "Failed...~%")
          (progn
            (decf retries)
            (invoke-restart 'retry))))))

(handler-bind ((always-error (make-handler)))
	(always-fail))