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On Nov 30, 2008, at 10:17 AM, Luke Palmer wrote:

On Sun, Nov 30, 2008 at 9:06 AM, Jake Mcarthur <[EMAIL PROTECTED]> wrote:
Seems a bit easy, I think.

  Data.List.permutations . nub

That is not what he meant.  Given:

 [1,1,2,2]

The results should be:

 [1,1,2,2]
 [1,2,2,1]
 [2,2,1,1]
 [1,2,1,2]
 [2,1,2,1]
 [2,1,1,2]

Heh, after a couple more seconds of thought, reversing the two composed functions fixes it:

    nub . permutations

Of course, neither my previous nonsolution nor this solution are efficient for long lists, but I think it serves as a decent reference implementation at least.

- - Jake
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