Re: Passing a list of symbols to function argument

[Stephen Berman]

On Fri, 29 Nov 2024 17:34:01 +0000 Heime via Users list for the GNU Emacs text 
editor <help-gnu-emacs@gnu.org> wrote:

> Why do I get
>
>    Wrong type argument: stringp, tabtrail
>
> When using the call
>
>    (poalatuk '(72 tabtrail global))
>
> to the function
>
>
> (defun poalatuk (actm-seqr)
>
>   (interactive
>     (let* ( (colw (read-number "Line Column: " 72))
>             (cseq '("extended" "disable" "tabtrail"))
>             (rsel (completing-read "Selector: " cseq nil t "tabtrail"))
>             (scope (completing-read "Scope: "
>                      '("global" "local") nil t "local")) )
>
>       ;; Pass a single list as argument
>       (list (list colw rsel scope))) )
>
>   ;; -------------------------------------------------------------
>
>   (message "poalatuk: %S" actm-seqr)
>
>   (let* ( (colw (nth 0 actm-seqr))              ;; Extract column width.
>           (rsel (intern (nth 1 actm-seqr)))     ;; Extract mode selector.
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^

The error happens here.  You passed '(72 tabtrail global) as the value
of the argument actm-seqr, so (nth 1 actm-seqr) returns the symbol
`tabtrail'.  But `intern' takes a string and returns the symbol (in the
obarray) whose name is given by the string.

Steve Berman