 | Haskell Core Libraries (base package) | Contents | Index |
| Control.Monad.State |
|
State monads.
Inspired by the paper Functional Programming with Overloading and Higher-Order Polymorphism, Mark P Jones (http://www.cse.ogi.edu/~mpj) Advanced School of Functional Programming, 1995.
| class Monad m => MonadState s m | m -> s where | ||
| ||
| modify :: MonadState s m => (s -> s) -> m () | ||
| gets :: MonadState s m => (s -> a) -> m a | ||
newtype State s a = State {
| ||
| runState :: State s a -> s -> (a, s) | ||
| evalState :: State s a -> s -> a | ||
| execState :: State s a -> s -> s | ||
| mapState :: ((a, s) -> (b, s)) -> State s a -> State s b | ||
| withState :: (s -> s) -> State s a -> State s a | ||
newtype StateT s m a = StateT {
| ||
| runStateT :: StateT s m a -> s -> m (a, s) | ||
| evalStateT :: Monad m => StateT s m a -> s -> m a | ||
| execStateT :: Monad m => StateT s m a -> s -> m s | ||
| mapStateT :: (m (a, s) -> n (b, s)) -> StateT s m a -> StateT s n b | ||
| withStateT :: (s -> s) -> StateT s m a -> StateT s m a | ||
| module Control.Monad | ||
| module Control.Monad.Fix | ||
| module Control.Monad.Trans |