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recursion/iterator question
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| Date: | -- (:) |
| From: | Nils Gesbert <nils.gesbert@e...> |
| Subject: | Re: [Caml-list] recursion/iterator question |
Li-Thiao-Té Sébastien <sayan@crans.org> a écrit :
» let iterate f l =
» let t = Array.of_list l in
» let n = Array.length t in
» let results = ref [] in
» for i = 0 to n-1 do
» for j = 0 to n-1 do
» for k = 0 to n-1 do
» results := f (t.(i),t.(j),t.(k)) :: results
» done done done
» ;;
Hi,
A functional version of this could be (assuming f is curryed, and without keeping results) :
let iter3 f l =
let rec it2 iter g = function
h::t -> iter (g h) l; it2 iter g t
| _ -> ()
in it2 (it2 List.iter) f l
But I think the goal was to iterate over triplets (a,b,c) with a < b < c, not over all triplets. If I am not mistaken, it suffices to replace the l on line 3 by t to get this behaviour.
--
Nils Gesbert