@benedek thanks, for me something as simple as this fails:

clojure
(let [thing 1
      other 2]
  <cursor>(+ thing other))
;;M-x cljr-extract-function
;;result open helm buffer and slightly refactored:
(defn
  [thing other]
  (+ thing other))

(let [thing 1
      other 2]
  ( thing other))