Haskell Control Flow

• if then else
  • price = if product == "milk" then 1 else 2
• guards
• case of

describe :: Integer -> String
describe n = case n of 0 -> "zero"
                       1 -> "one"
                       2 -> "an even prime"
                       n -> "the number " ++ show n
					   
-- parse country code into country name, returns Nothing if code not recognized
parseCountry :: String -> Maybe String
parseCountry "FI" = Just "Finland"
parseCountry "SE" = Just "Sweden"
parseCountry _ = Nothing
 
flyTo :: String -> String
flyTo countryCode = case parseCountry countryCode of Just country -> "You're flying to " ++ country
                                                     Nothing -> "You're not flying anywhere"