warn on variable which is marked unused, but is used anyway

[jimka2001]

clj-kondo already supports flagging unused variable declarations.
I can name a variable starting with _ to signal that I don't want the warning for a particular variable. However, if I then accidentally use such a variable, clj-kondo does not warn me that I've used a variable marked as unused.

I would like such variable declarations (or use sites) to be flagged.

(defn foo (f g) ;; g is unused, so warn
  {:sigma (fn (x _y) (f x))   ;; correct _y is unused, but don't warn
   :alpha (fn (x _y)  (f x _y))})   ;; _y is used, so warn

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[borkdude]

@jimka2001 This is now available in the newest clj-kondo under :used-underscored-binding.