sd-set-variable-status

[CF_Lum]

I have the following code, I would like the variable PART2 & PART3 to be visible when click next susquently.

(sd-defdialog 'test_dialog
:dialog-title "test"
:variables
'(
(PART1 :value-type :part)
(PART2 :value-type :part
:initial-visible nil)
(PART3 :value-type :part
:initial-visible nil)
(NEXT_PA :toggle-type :wide-toggle
:title "Next Part"
:push-action (progn
(incf no_pa)
(sd-set-variable-status (nth no_pa pa_list) :visible t))
:after-input (if (= no_pa 2) (sd-set-variable-status 'next_pa :visible nil)))
)
:after-initialization '(progn
(setf no_pa 0)
(setf pa_list '('part1 'part2 'part3)))
:ok-action
'(progn
(sd-display-message (format nil "Total part(s) selcted ~A" (+ no_pa 1)))
)
); sd-defdialog

I know by replacing the
(sd-set-variable-status (nth no_pa pa_list) :visible t) to
(case no_pa ...
will do the trick, but it is possible to do it this way?