Hey Jason, would you mind giving a short idea of what the point of Bird's implementation is / from what properties it is derived? Also, running the QuickCheck tests you added, it doesn't give the same output (order) as nub. On 15/07/13 13:26, Jason Dagit wrote:
Richard Bird has a book, "Pearls of Functional Algorithm Design" that is meant to teach a form of deriving algorithms from the properties we ask of them. In this book, he gives a possible derivation of ordNub, simply called nub in the book, following the methodology he is teaching. He notes in the text that this derivation feels more complicated than it ought.
Here is his version: http://lpaste.net/87625
I just sent you a pull request to add that one and S.toList . S.fromList that was suggested in this thread. I don't think those two implementations are faster than the others but it's nice to have them for completeness.
Jason