Как измерить общую длину выделенных линий?

(defun C:Dlina (/ Nab Sum i Curve Param)
(vl-load-com)
(if (setq Nab (ssget))
(progn
(setq Sum 0 i 0)
(repeat (sslength Nab)
(setq Curve (vlax-ename->vla-object (ssname Nab i))
i (1+ i)
Param (vl-catch-all-apply 'vlax-curve-getEndParam
(list Curve))
)
(if (not (vl-catch-all-error-p Param))
(setq Sum (+ Sum (vlax-curve-getDistAtParam Curve
Param)))
)
)
)
)
(princ (strcat "\nСумма длин выбранных элементов равна: " (rtos Sum 2 2)))
(prin1)
)

(defun lin-len ()
  (vl-load-com)
  (apply '+
     (mapcar 'vla-get-length
         (mapcar 'vlax-ename->vla-object
             (vl-remove-if
               'listp
               (mapcar 'cadr
                   (ssnamex
                     (ssget '((0 . "line")))
                   )
               )
             )
         )
     )
  )
)