; error: bad argument type: stringp nil In DCL

[Boopathy_Karthikeyan]

hi i practice with Lisp in below link,  http://www.afralisp.net/dialog-control-language/tutorials/getting-started-part-2.php

this lisp contains Name and Age i try to add the date Of Birth but there is a error popup "; error: bad argument type: stringp nil"

i cant understand where did i missed

could you help me on this?

i attached my lisp file below 

Best Regards,

Boopathy k

[ВeekeeCZ · Accepted solution]

The issue is that in your dcl file is Key instead of key for dob value.

I've tried to record the steps that should help you to locate the issue in the future. See the SCREENCAST

- run VLIDE, open the lsp

- debug / tick Break On Error 

- run your program

- go to vlide, locate the error line by debug / Last Break Source

- add the break point (hand icon) at the beginning of the line, add all suspicion variables  to watch(glasses), 

- run the program

- now step by step watch the variables - you'll see that dob is nil - something is wrong, it should be some string

Good luck, next time post it to THIS forum.

[Boopathy_Karthikeyan]

thanks BeekeeCZ

[Anonymous]

sir good day....i have a problem like this....i cant open my file....and this sentence above is appearing....please help me

[cadffm]

How can we help without your code?
And why you don't start a new thread, is it happen in a dcl?

One lispfunction want a string, but "you" give nothing(nil).
Debug your code and you will find the problem.

https://knowledge.autodesk.com/search-result/caas/CloudHelp/cloudhelp/2016/ENU/AutoCAD-AutoLISP/file...

[Anonymous]

hello sir/madam,
good day....may i know where can i find this visual lisp that you are
saying?because im not familiar with it....can i have a step by step
instruction about how to overcome my problem if its ok with you....thank
you and hope to hear from you soon....

[cadffm]

Command VLIDE / VLISP

But it can not help you if you are not familiar with lisp.

Is it your own code? If not, sorry I can not teach you from scratch without the code.

Or you add markers like (princ "\ninfo1")..
to check where the problem is.