(chunk-first s)
(let [chunked-cons (seq (range 1 42))
first-chunk (chunk-first chunked-cons)]
(class chunked-cons)
;; => clojure.lang.ChunkedCons
(class first-chunk)
;; clojure.lang.ArrayChunk
;; Demonstrating chunk size of 32.
(.nth first-chunk 0)
;; => 1
(.nth first-chunk 31)
;; => 32
)