sq2.clj

;; take your make-guess function
(defn make-guess [guess]
  (/ (+ (/ 2.0 guess) guess) 2.0))

;; and iterate to a lazy-seq of approximations
(def guesses (iterate make-guess 1.0))

;; then we can zip the list with itself, but shifted one value
;; this gives us a seq of guess pairs.
(def guess-pairs
  (map list guesses (rest guesses)))

;; we can stop when they reach a fixed point. Then take one value
;; from that pair.
(->> guess-pairs
     (drop-while (fn [[x y]] (not= x y)))
     first
     first)