无标题

;;; Function gp:getPointInput will get path location and size
(defun gp:getPointInput    ()
  (alert
    "Function gp:getPointInput will get user drawing input"
  )
  ;; For now, return T, as if the function worked correctly.
  T
)
;;; Function gp:getDialogInput will get path parameters
(defun gp:getDialogInput ()
  (alert
    "Function gp:getDialogInput will get user choices through a dialog"
  )
  ;;For now, return T, as if the function worked correctly.
  T
)
;;; Function gp:drawOutline will draw the path boundary
(defun gp:drawOutline ()
  (alert
    (strcat "This function will draw the outline of the polyline" 
        "\nand return a polyline entity name/pointer."
    )
  )
  ;; For now, simply return a quoted symbol. Eventually, this
  ;; function will return an entity name or pointer.
  'SomeEname
)
;;; Function C:GPath is the main program function and defines the 
;;; AutoCAD GPATH command.
(defun C:GPath ()
  ;; Ask the user for input: first for path location and
  ;; direction, then for path parameters. Continue only if you have
  ;; valid input.
  (if (gp:getPointInput)      ; 
    (if (gp:getDialogInput)
      (progn
        ;; At this point, you have valid input from the user.
        ;; Draw the outline, storing the resulting polyline 
        ;; "pointer" in the variable called PolylineName.
        (setq PolylineName (gp:drawOutline))
        (princ "\nThe gp:drawOutline function returned <")
        (princ PolylineName)
        (princ ">")
        (Alert "Congratulations - your program is complete!")
      )
    (princ "\nFunction cancelled.")    
   )
   (princ "\nIncomplete information to draw a boundary.")
  )
  (princ)  ; exit quietly
)
;;; Display a message to let the user know the command name.
(princ "\nType gpath to draw a garden path.")
(princ)

如果没有特别指定的值，例如“T”，方程会返回方程内最后一个语句的结果，在上面中，许多会返回一个“nil”

定义方程时，加入的参数“/”代表使用局部变量。