Get objects in one point

Discussion of other Lisp dialects (Arc, Clojure, AutoLisp, XLISP, etc.)
Post Reply
Posts: 1
Joined: Wed Dec 14, 2011 12:52 am

Get objects in one point

Post by arrowman » Wed Dec 14, 2011 1:55 am

I try to choose objects in one point. I use:

Code: Select all

(setq PtsList ( list (setq P1(getpoint "P1")) (setq p2(getpoint P1 "P2")) ))
setq ss (ssget "CP" PtsList))
(prin1 (sslength ss ))
I choose two times the same point. And I have error:
; ----- Error around expression -----
; error : bad argument type <NIL> ; expected SELECTIONSET at [SSLENGTH]
Please, help me:-)


Posts: 538
Joined: Sat Aug 09, 2008 10:44 am
Location: Newton, MA

Re: Get objects in one point

Post by nuntius » Wed Dec 14, 2011 9:25 am

From a web search, this appears to be Autolisp.

Here's your code, refactored to be more readable to my eye.

Code: Select all

(setq P1 (getpoint "P1"))
(setq p2 (getpoint P1 "P2"))))
(setq PtsList (list P1 p2))
(setq ss (ssget "CP" PtsList))
(prin1 (sslength ss))
Based on your error message, it appears that the ssget is failing and returning NIL instead of a SELECTIONSET object; but I don't know enough about that function to understand why.

Post Reply