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When I start Emacs, I get the error message: Symbol's value as variable is void: n I am pretty sure, it is just a typo in my init.el, but how can I find it?

Shouldn't there be a debugger, which tells me exactly where this variable n shows up?

My question is, whether it exists, and if it exists, where it is?

I would also appreciate best practices for debugging the init.el (or elisp in general) and also resources to learn this.

I loaded emacs with --debug-init and the backtrace gives me:

Debugger entered--Lisp error: (void-variable n)
load-with-code-conversion("/home/xx/.emacs.d/init.el" "/home/xx/.emacs.d/init.el" t t)
load("/home/xx/.emacs.d/init" noerror nomessage)
startup--load-user-init-file(#f(compiled-function () #<bytecode -0xfb4a62eb1ee4990>)   #f(compiled-function () #<bytecode -0x1f3c686ddc0ca9b5>) t)
command-line()
normal-top-level()

Which is unhelpful. What does it try to communicate to me?

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  • I added a random n at top level of one of the files that I load when I start emacs and then I invoked emacs with emacs --debug-init. I got the following message: Debugger entered--Lisp error: (void-variable n) eval-buffer(#<buffer *load*-97476> nil "/some/path/org-config.el" nil t) ; Reading at buffer position 32678. Opening the file and going to position 32678 (with M-g c 32678) took me directly to the errant n. I don't understand why the buffer position is missing from your backtrace. Did you leave it out by any chance?
    – NickD
    Apr 10, 2023 at 22:06
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    @NickD: That position comes from backtrace--print-func-and-args (since 27.1) and from the comments is specific to eval-buffer usage -- which is happening in your case, but seemingly not for Sinthoras. Maybe load is doing something slightly different in different versions/cases?
    – phils
    Apr 10, 2023 at 23:02
  • Yes, maybe - the OP can perhaps add to the question the Emacs version they are running.
    – NickD
    Apr 11, 2023 at 1:11
  • I am on Emacs 27.1. And I did not leave out that line on my backtrace (since it was one of the points of the question, how I can make it show up, such that the computer tells me where the errant is, and I don't have to search it by myself.)
    – Sinthoras
    Apr 11, 2023 at 8:04

1 Answer 1

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I would also appreciate best practices for debugging the init.el (or elisp in general) and also resources to learn this.

In a case like this, I'd say start by bisecting your init file. Use command comment-region to comment out 1/2, then 3/4, 7/8,... of your init file, to find the culprit. With C-u it uncomments, instead of comments, the region.

If you want, if you've narrowed the problem down to some function (something within that function is causing the problem), then use M-x debug-on-entry for that function.

That opens the debugger for each invocation of that function. Step through the debugger with d (or c to skip diving down inside a function). You'll see exactly what's going on and what goes wrong.


That said, there are lots of questions on this site about Symbol's value as a variable is void. Try searching for that on the site, to see if your question is a duplicate. If it is, please delete it.

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  • Before posting, I already searched on this site about my question, and was surprised that I did not find it. The questions I found were all quite specific about specific Symbol's value as a variable is void errors, while I am asking about general principles.
    – Sinthoras
    Apr 11, 2023 at 8:01
  • Good. Thanks for searching.
    – Drew
    Apr 11, 2023 at 14:57

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