리습 오류 도와주세요…

다른분께서 올려주신 리습인데
; 오류: 잘못된 인수 유형: (or stringp symbolp): nil 라고 오류가 뜨네요…
해결법 아시는 분 계실까요?

; 수직 단축키 11

; 수평 단축키 12

; 무한선 지우기 22
; 레이어는 xline 로 지정되었습니다.

(defun c:11 ()
(setvar “cmdecho” 0)
(setq oldlayer (getvar “clayer”))
(if (= (tblsearch “layer” “xlline”) nil)
(command “-layer” “m” “xline” “”))
(command “-layer” “s” “xline” “”)

(command “xline” “v”)
(while (= 1 (getvar “cmdactive”))
(command pause))

(setvar “clayer” oldlayer)
(princ)
)

(defun c:12 ()
(setvar “cmdecho” 0)
(setq oldlayer (getvar “clayer”))
(if (= (tblsearch “layer” “xlline”) nil)
(command “-layer” “m” “xline” “”))
(command “-layer” “s” “xline” “”)

(command “xline” “h”)
(while (= 1 (getvar “cmdactive”))
(command pause))

(setvar “clayer” oldlayer)
(princ)
)

(defun c:22 ()
(setvar “cmdecho” 0)
(if (setq s1 (ssget “_x” ‘((0 . “xline”))))
(command “_.erase” s1 “”)
)
(princ)
)

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