IdeSession.Strict.StateT

Version on StateT which evaluates the state strictly at every step

Transformer

newtype StrictStateT s m a

Constructors

StrictStateT

Fields

runStateT :: s -> m (a, s)

Instances

Monad m => MonadState s (StrictStateT s m)

MonadTrans (StrictStateT s)

Monad m => Monad (StrictStateT s m)

Monad m => Functor (StrictStateT s m)

Monad m => Applicative (StrictStateT s m)

modify :: MonadState s m => (s -> s) -> m ()

Monadic state transformer.

Maps an old state to a new state inside a state monad. The old state is thrown away.

     Main> :t modify ((+1) :: Int -> Int)
     modify (...) :: (MonadState Int a) => a ()

This says that modify (+1) acts over any Monad that is a member of the MonadState class, with an Int state.

evalStateT :: Monad m => StrictStateT s m a -> s -> m a

execStateT :: Monad m => StrictStateT s m a -> s -> m s

As base monad

type StrictState s = StrictStateT s Identity

runState :: StrictState s a -> s -> (a, s)

evalState :: StrictState s a -> s -> a

execState :: StrictState s a -> s -> s