Insertion sort in clojure

insertion-sort.clj

(defn insert [l k]
"Function to do insert in sorted order"
      (concat (filter #(< % k) l)  [k] (filter #(> % k) l)))

(defn isort [l]
"Insertion sort"
      (loop [r []
             l  l]
         (if (empty? l)
             r
             (recur (insert r (first l)) (rest l)))))

;;Tested in REPL
;;user> (isort (shuffle (range 10)))
;;(0 1 2 3 4 5 6 7 8 9)


;;TODO - an exercise for another day.
;;1. A lazy version 
;;2. A version with actual in place inserts in to a transient collection 

But in your filter maybe should use '<='

(defn insert [l k]
"Function to do insert in sorted order"
      (concat (filter #(<= % k) l)  [k] (filter #(> % k) l)))

What about split-with?

(defn insert [list newElement]
    (let [split (split-with #(<= % newElement) list)]
    (concat
        (first split)
        [newElement]
        (second split))))