Not much better. You could define shiftl such that is does a single traversal and returns both the last element and all but the last. That will save you one traversal. On Feb 4, 2007, at 18:44 , Eric Olander wrote:
Hi, I'm still somewhat new to Haskell, so I'm wondering if there are better ways I could implement the following functions, especially shiftl:
moves the first element to the end of the list shiftr :: [a] -> [a] shiftr [] = [] shiftr (x:y) = y ++ [x]
moves the last element to the head of the list shiftl :: [a] -> [a] shiftl [] = [] shiftl x = [last x] ++ init x
-Eric _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe