reverse a sequence without reverse or rseq

[MarisO]

Do you know of any trick to reverse a sequence without reverse or
rseq ?

I wrote it like this:

((fn rev
([s] (rev '() s))
([r s] (if (seq s) (rev (cons (first s) r) (rest s)) r )) )
'[1 2 3 5] )


https://gist.github.com/1132357


I wonder if it can be written more shortly.

[Mark Rathwell]

user> (source reverse)

(defn reverse

  "Returns a seq of the items in coll in reverse order. Not lazy."

  {:added "1.0"}

  [coll]

    (reduce conj () coll))

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[Alan Malloy]

(into () [1 2 3 5])

[Aaron Cohen]

On Mon, Aug 8, 2011 at 2:29 PM, MarisO <maris.o...@gmail.com> wrote:

Another way to do it would be to follow the example of shuffle and defer to Java collections:

(defn reverse

  "Return coll, reversed"

  [coll]

  (let [al (java.util.ArrayList. coll)]

    (java.util.Collections/reverse al)

    (clojure.lang.RT/vector (.toArray al))))