gistfile1.el

(defadvice delete-backward-char
  (around stop-when-beginning-of-line (n &optional killflag) activate)
  "前の行まで削除しない"
  (unless (equal (point) (point-at-bol))
     ad-do-it))

(defadvice delete-char
  (around stop-when-end-of-line (n &optional killflag) activate)
  "次の行まで削除しない"
  (unless (equal (point) (point-at-eol))
    ad-do-it))