From the Clojure Data Analysis Cookbook... an useful display of the lazy-seq macro.

gistfile1.clj

(defn lazy-read-csv
  [csv-file]
  (let [in-file (io/reader csv-file)
       csv-seq (csv/read-csv in-file)
       lazy (fn lazy [wrapped]
              (lazy-seq
                (if-let [s (seq wrapped)]
                  (cons (first s) (lazy (rest s)))
                  (.close in-file))))]
   (lazy csv-seq)))

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