Bubble-sort in Clojure
Following on with my exploration into implementing common sorting algorithms in Clojure, today we have the Bubble-sort. This sort works by iteratively passing through the supplied sequence, swapping the current element with the next if it is comparably greater. The operation is complete when a pass through the sequence does not result in a swap occurring.
(defn- bubble [ys x] (if-let [y (peek ys)] (if (> y x) (conj (pop ys) x y) (conj ys x)) [x])) (defn bubble-sort [xs] (let [ys (reduce bubble  xs)] (if (= xs ys) xs (recur ys)))) (bubble-sort [3 2 1]) ; [1 2 3]
Looking at the implementation above you will notice we use a
reduce operation with a private
bubble function which provides us with the pass through the sequence.
Upon each pass the result is checked against the input to see if a swap has occurred, in the case of them both being equal we have completed the sorting process.