14.11.2012 Views

Curry: An Integrated Functional Logic Language

Curry: An Integrated Functional Logic Language

Curry: An Integrated Functional Logic Language

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

-- Sequential conjunction of constraints<br />

(&>) :: Success -> Success -> Success<br />

c1 &> c2 | c1 = c2<br />

-- Maybe type<br />

data Maybe a = Nothing | Just a<br />

maybe :: b -> (a -> b) -> Maybe a -> b<br />

maybe n _ Nothing = n<br />

maybe _ f (Just x) = f x<br />

-- Either type<br />

data Either a b = Left a | Right b<br />

either :: (a -> c) -> (b -> c) -> Either a b -> c<br />

either f _ (Left x) = f x<br />

either _ g (Right x) = g x<br />

-- Monadic IO<br />

data IO a -- conceptually: World -> (a,World)<br />

(>>=) :: IO a -> (a -> IO b) -> IO b<br />

return :: a -> IO a<br />

(>>) :: IO a -> IO b -> IO b<br />

a >> b = a >>= (\_ -> b)<br />

done :: IO ()<br />

done = return ()<br />

putChar :: Char -> IO ()<br />

getChar :: IO Char<br />

readFile :: String -> IO String<br />

writeFile :: String -> String -> IO ()<br />

appendFile :: String -> String -> IO ()<br />

putStr :: String -> IO ()<br />

55

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!