
Hi! A couple of months ago, I wrote an exam in an introductory Haskell course and failed, all because of an assignment that I was convinced would work, but for some reason, it didn't. The assignment was to write a function that would take a line, then determine whether it's a palindrome or not. My code follows: palindrome :: IO () palindrome = do putStr "Type in a word" s <- getLine case s of (s == reverse s) -> putStrLn (s ++ " is a palindrome") otherwise -> putStrLn (s ++ " is not a palindrome") The interesting thing is, that if I change the "case ... of" statement to an "if ... then ... else" statement, this magically starts to work. Since I no longer am enrolled (I have to take the course next year), I can't ask a teacher, but my curiosity still bugs me. Why doesn't this work? And why does it work with a "if ... then ...else" statement?