Sorry for annoying you all, i'm just very eager to move on with this and solve it. so far i have; equalChar :: Char -> Char -> Bool equalChar x n | x == n = True | otherwise = False equalString :: String -> String -> Bool equalString [] [] = True equalString [] (c':s') = False equalString(c:s) [] = False equalString(c:s)(c':s') = equalChar c c'^ equalString s s' this function is to see if one string is equal to another. but when i compile this i get the error; - Instance of Integral Bool required for definition of equalString does anyone know why i am getting this error and what i will need to do to transform the function above so that it checks is a list a subsequence of another list Peter Stranney --------------------------------- Do you Yahoo!? Yahoo! Mail - You care about security. So do we.