safadao.el

(defun safadao ()
  (interactive) ;; interactive interpreter
  (let (birthdate) ;; create variable birthdate, it will be avaliable for nested stuff
    (progn (setq birthdate (read-no-blanks-input "digite sua data de nascimento: "))) ;; set birthdate to whatever user inputs

    (if (and (< 7 (length birthdate))
             (> 9 (length birthdate)))
        (let ((sum 0) list day month year safadeza)
      (progn
        (setq list (split-string birthdate "/"))
        (setq day (string-to-int (nth 0 list)))
        (setq month (string-to-int (nth 1 list)))
        (setq year (string-to-int (nth 2 list)))

        (while (> month 0)
          (setq sum (+ sum month))
          (setq month (1- month)))

        (setq safadeza (+ sum (* (/ year 100.0) (- 50 day))))
        (message (format "voce é %s safado e %s anjo." safadeza (-100 safadeza)))
        )
      )
      (message "por favor, digite o formato certo, animal")
      )
    )
  )
(safadao)