Hello, For practising pattern matching and recursion I did recreate some commands of Data,list. My re-implementation of ++ : plusplus :: [a] -> [a] -> [a] plusplus [] [] = [] ; plusplus [] (xs) = xs plusplus (xs) [] = xs plusplus (xs) yx = plusplus' (reverse xs) yx plusplus' :: [a] -> [a] -> [a] plusplus' [] (xs) = xs plusplus' (x:xs) yx = plusplus' xs (x:yx) main = print $ plusplus ["a","b"] ["c","d"] my re-implementation of init : import Data.Maybe -- | The main entry point. init' :: [a] -> Maybe [a] init' [] = Nothing init' [x] = Just [] init' (x:xs) = Just (x:fromMaybe xs (init' xs)) main = print . init' $ [1,3] my re-implementation of last : -- | The main entry point. last' :: [a] -> Maybe a last' [] = Nothing last' [x] = Just x last' (_:xs) = last' xs main = print . last' $ [] Now I wonder if these solutions are the haskell way ? if not so, how can I improve them , Roelof --- Dit e-mailbericht is gecontroleerd op virussen met Avast antivirussoftware. http://www.avast.com