gistfile1.hs

whatWentWrong :: [LogMessage] -> [String]
whatWentWrong msgs = map (\m -> case m of 
                                  (LogMessage _ _ s) -> s
                                  _ -> "")
                       $ dropWhile (\m -> case m of
                                       (LogMessage (Error severity) _ _) -> severity >= 50
                                       _ -> False) .
                         filter (\m -> case m of
                                       (LogMessage (Error _) _ _) -> True
                                       _ -> False) 
                         $ inOrder $ build msgs