module Main where import Data.Function(fix) import Prelude hiding (last) unwrap :: ([a] -> a) -> a -> [a] -> a unwrap f a as = f (a:as) wrap :: (a -> [a] -> a) -> [a] -> a wrap f [] = error "wrap _ []" wrap f (a:as) = f a as last :: [a] -> a last [] = error "last []" last [a] = a last (_:a:as) = last (a:as) main :: IO () main = print (last "hello")