Why???; error: bad argument type: lselsetp nil

[Anonymous]

WHY?   ; error: bad argument type: lselsetp nil

(DEFUN me1( string default)
    (PRINC string)   
    (PRINC "< ")
    (PRINC default)
    (PRINC " >:")
    (PRINC "")
)
(DEFUN c:SA ( / exp g_ext g_int n_g_ext e_ext v_e_ext1 v_e_ext2
  v_e_ext n_int s_int s_int1 e_int v_e_int total total1)
 (setvar "cmdecho" 0)
   (setvar "menuecho" 1)
 (IF  (= v_default nil)
  (SETQ v_default 5)
  (SETQ v_default v_intro)
 )
 (SETQ  v_intro (GETINT (me1 "\nNumero de precision despues de Punto Recomendable 5:" v_default)))(TERPRI)
 (IF  (= v_intro nil)
  (SETQ v_intro v_default)
 )
 (SETQ  exp (expt 10 v_intro))
 (SETQ g_ext (SSGET "X" '(   (0 . "POLYLINE")
        (8 . "GROS*")
         )
      )
       g_int (SSGET "X" '(   (0 . "POLYLINE")
        (8 . "RM*")
         )
      )
     n_g_ext (SSLENGTH g_ext)
 )
 (IF (/= n_g_ext 1)
     (PROGN
  (princ "\n\tExisten en el dibujo varias Areas Gros")
  (PRINC)
     )
 )
 (SETQ   e_ext (SSNAME g_ext 0))
 (command "_area" "o" e_ext )
 (SETQ   v_e_ext1 (GETVAR "area")
  v_e_ext  (* v_e_ext1 exp)
  v_e_ext  (fix v_e_ext)
  n_int 0
   s_int 0
 )
 (REPEAT (SSLENGTH g_int)
  (SETQ e_int (SSNAME g_int n_int))
  (command "_area" "o" e_int )
  (SETQ  v_e_int (GETVAR "area")
   v_e_int (* v_e_int exp)
   v_e_int (fix v_e_int)
    s_int (+ s_int v_e_int )
    n_int (+ n_int 1))
 )
 (SETQ g_ext nil)
 (SETQ g_int nil)
 (SETQ total (float (- v_e_ext  s_int)))
 (SETQ total1 (float (/ total exp)))
 (TEXTPAGE)
 (PROMPT "Area total:            ")
 (PRIN1 v_e_ext1)(TERPRI)
 (PROMPT "Resultante total Extena:      ")
 (PRIN1 v_e_ext)(TERPRI)
 (PROMPT "Resultantes totales Internas: ")
 (PRIN1 s_int)(TERPRI)
 (PROMPT "Area faltante en Metros       ")
 (PRIN1 total1)(TERPRI)
 (PROMPT "Si es - Sobran Areas, Si es + Faltan Areas")
 (PRINC)
        (setvar "cmdecho" 1)
   (setvar "menuecho" 0)
)
(PRINC
 "\n\tSe cargo la rutina de Suma de areas ")
(PRINC
 "\n\tInicia con SA ")

[Anonymous]

if im not mistaken I don't think ssget will work with polyline sub entities which is why are you getting a nil error, but you should wait for more experienced posters to weigh in.

[Kent1Cooper · Accepted solution]

That means something is looking for a selection set to work with, and what it's getting is nil.  That would happen if there were no Polylines on either or both groups of the GROS* or RM* Layers.  The g_ext and/or g_int variable(s) will be nil, so some (sslength) or (ssname) function will not find a selection set.

I wonder whether what you are working with are really Lightweight Polylines.  The "POLYLINE" entity type in entity data is used for "heavy" 2D Polylines and 3D Polylines.  Try:

  (0 . "LWPOLYLINE")
in place of

  (0 . "POLYLINE")
in your (ssget) functions.

[Anonymous]

Thank you Kent1Cooper . I really help me

[Kent1Cooper]

---

@Anonymous wrote:

Thank you Kent1Cooper . I really help me

---

You're welcome -- you'll get used to the need to distinguish heavy from lightweight Polylines.  I have often wondered why they set it up so that the PLINE command does not create something whose entity-type name is (0 . "POLYLINE") by default, but only when you consciously change the PLINETYPE System Variable to 0 before you make one, or convert a lightweight one to make it "heavy."  If it were up to me, I would have called lightweight Polylines (0 . "POLYLINE") and given the entity-type names (0 . "2DPOLYLINE") and (0 . "3DPOLYLINE") to the other types.  That would coordinate better with their ObjectName VLA Properties, and the second 100-code entry in their entity data.  And I would have introduced a 2DPOLY command.  I'm sure it's an issue of compatibility with older versions of AutoCAD before there were lightweight Polylines.

[oliver.wackenreuther]

@Kent1Cooper, this is a decade old post but your suggestion helped me out.

for error: bad argument type: lselsetp nil I reviewed the ssget variables and found the issue in my code.

Hoping this helps others in the future as well.