gistfile1.txt

nqueen = [egison| (lambda [$n]
                     (match-all (between 1 n) (Multiset Integer)
                      [<cons $a_1
                       (loop $l $i (between 2 n)
                        <cons (loop $l1 $i1 (between 1 (- i 1))
                               (& ^,(- a_i1 (- i i1))
                                  ^,(+ a_i1 (- i i1))
                                   l1)
                               $a_i)
                        l>
                        <nil>)>
                       {@(loop $l $i (between 1 n)  {a_i @l} {})}])) :: Int -> [[Int]]|]

> nqueen 5
[[1,3,5,2,4],[1,4,2,5,3],[2,4,1,3,5],[2,5,3,1,4],[3,1,4,2,5],[3,5,2,4,1],[4,1,3,5,2],[4,2,5,3,1],[5,2,4,1,3],[5,3,1,4,2]]