doall, partition 2

(ns mytest3)

(def file-path "/Users/me/Desktop/temp/bob.txt")
;(def file-path "/Users/me/Downloads/3MB-file.m4a")

(def group-by-twos
  (fn [a-list]
    (let [first-two (fn [a-list] (list (take 2 a-list)))
          the-rest-after-two (fn [a-list] (rest (rest a-list)))
          only-two-left? (fn [a-list] (if (= (count a-list) 2) true false))]
      (loop [result '() rest-of-list a-list]
        (if (empty? rest-of-list)
          result
          (recur (doall (concat result (first-two rest-of-list)))
                 (doall (the-rest-after-two rest-of-list))))))))

(def get-the-file
  (fn [file-name-and-path]
    (let [the-file-pointer
            (new java.io.RandomAccessFile (new java.io.File file-name-and-path) "r")
          intermediate-array (byte-array (.length the-file-pointer))] ;reserve space for final length
      (.readFully the-file-pointer intermediate-array)
      (partition 2 (seq intermediate-array)))))
      ;(group-by-twos (seq intermediate-array)))))
   
(spit "bob2.txt" (some-pretty-print-here (get-the-file file-path)))