Re: How to avoid compiler warning `unused lexical variable' for `dolist' or `dotimes'?

[Robert Thorpe]

I'm still struggling to see how this isn't a bug.

Here is the original code that Jean Louis posted:

> (defun db/table-id-plist (table id pg)
>   "Returns plist for table by its table_id"
>   (let* ((columns (db/table-columns table pg))
>        (sql (db/sql-by-columns table columns id))
>        (values (rcd-sql-first sql pg))
>        (values (append values nil))
>        (length (length columns))
>        (plist '()))
>     (dotimes (i length plist)
>       (setf plist (plist-put plist (intern (elt columns i)) (elt values 
> i))))))
 
And here is the original warning:

> rcd-db.el:841:1: Warning: Unused lexical variable ‘i’

Jean Louis actually is using the variable i, it's not unused.

You could argue that the warning should be "The three element version of
dotimes is discouraged".  But I can't see how you can argue that the
warning is right, since i is used.

BR,
Robert Thorpe