Symbol's function definition is void on built-in variables?

Question

For some reason I am getting errors for built-in variables that are available in the documentation.

For instance, evaluating in the scratch buffer the following all return:

Symbol's function definition is void:

This is so weird because there is documentation for all of these, they show up in auto-complete and I see other users using them.

I can not use these in my .emacs or anywhere else. Interestingly however, I can set some of them using customize. For instance:

(display-time-24hr-format t) does work in the customize block

Does anyone have any advice?

Kaushal Modi · Accepted Answer · 2016-08-02 18:57:12Z

2

You get Symbol's function definition is void because those are variables, not functions.

Below will work:

M-: emacs-major-version

Below will not work:

M-: (emacs-major-version)

answered Aug 2, 2016 at 18:57

Kaushal Modi

25.4k4 gold badges76 silver badges182 bronze badges

Ah yes, silly mistake. However, can you help me with (display-time-24-hr-format t) which I am pretty sure is a function?
– Startec
Aug 2, 2016 at 19:00
2

@Startec Nope, That's a variable too. Looks like you are partially evaluating the auto-generated customize forms.. (setq display-time-2hr-format t) will work. If something shows up in C-h v, that's a variable. If something shows up in C-h f, that's a function.
– Kaushal Modi
Aug 2, 2016 at 19:02
You should be evaluating the whole (customize-set-variables ..) form, not just elements of array in it.
– Kaushal Modi
Aug 2, 2016 at 19:04
I am still learning lisp and wanted to write it myself. I thought I could just use that because it looked like (blink-cursor-mode t) These slight differences are rough.
– Startec
Aug 2, 2016 at 19:06
@Startec blink-cursor-mode is both a function and a variable, the customize-set-variables form refers to the variable.
– npostavs
Aug 2, 2016 at 19:33

| Show 1 more comment

1 Answer 1