Copyright	(c) Adam C. Foltzer 2013
License	BSD3
Maintainer	acfoltzer@gmail.com
Stability	experimental
Portability	non-portable (requires rank-2 types for runST)
Safe Haskell	None
Language	Haskell98

Control.Monad.ST.Persistent

Contents

The Persistent ST Monad
The Persistent ST Monad transformer

Description

This library provides support for a persistent version of the ST monad. Internally, references are backed by a IntMap, rather than being mutable variables on the heap. This decreases performance, but can be useful in certain settings, particularly those involving backtracking.

Synopsis

type ST s = STT s Identity
runST :: (forall s. ST s a) -> a
data STT s m a
runSTT :: Monad m => (forall s. STT s m a) -> m a

The Persistent `ST` Monad

type ST s = STT s Identity #

A persistent version of the ST monad.

runST :: (forall s. ST s a) -> a #

Run a computation that uses persistent references, and return a pure value. The rank-2 type offers similar guarantees to runST.

The Persistent `ST` Monad transformer

data STT s m a #

Instances

MonadTrans (STT s) #
Instance details Defined in Control.Monad.ST.Persistent.Internal Methods lift :: Monad m => m a -> STT s m a #
Monad m => MonadRef (STRef s) (STT s m) #
Instance details Defined in Data.STRef.Persistent Methods newRef :: a -> STT s m (STRef s a) # readRef :: STRef s a -> STT s m a # writeRef :: STRef s a -> a -> STT s m () # modifyRef :: STRef s a -> (a -> a) -> STT s m () # modifyRef' :: STRef s a -> (a -> a) -> STT s m () #
Monad m => Monad (STT s m) #
Instance details Defined in Control.Monad.ST.Persistent.Internal Methods (>>=) :: STT s m a -> (a -> STT s m b) -> STT s m b # (>>) :: STT s m a -> STT s m b -> STT s m b # return :: a -> STT s m a # fail :: String -> STT s m a #
Functor m => Functor (STT s m) #
Instance details Defined in Control.Monad.ST.Persistent.Internal Methods fmap :: (a -> b) -> STT s m a -> STT s m b # (<$) :: a -> STT s m b -> STT s m a #
Monad m => Applicative (STT s m) #
Instance details Defined in Control.Monad.ST.Persistent.Internal Methods pure :: a -> STT s m a # (<>) :: STT s m (a -> b) -> STT s m a -> STT s m b # liftA2 :: (a -> b -> c) -> STT s m a -> STT s m b -> STT s m c # (>) :: STT s m a -> STT s m b -> STT s m b # (<*) :: STT s m a -> STT s m b -> STT s m a #
MonadIO m => MonadIO (STT s m) #
Instance details Defined in Control.Monad.ST.Persistent.Internal Methods liftIO :: IO a -> STT s m a #
MonadPlus m => Alternative (STT s m) #
Instance details Defined in Control.Monad.ST.Persistent.Internal Methods empty :: STT s m a # (<\|>) :: STT s m a -> STT s m a -> STT s m a # some :: STT s m a -> STT s m [a] # many :: STT s m a -> STT s m [a] #
MonadPlus m => MonadPlus (STT s m) #
Instance details Defined in Control.Monad.ST.Persistent.Internal Methods mzero :: STT s m a # mplus :: STT s m a -> STT s m a -> STT s m a #

runSTT :: Monad m => (forall s. STT s m a) -> m a #

Run a computation that uses persistent references, and return a pure value. The rank-2 type offers similar guarantees to runST.

The Persistent ST Monad

The Persistent ST Monad transformer

The Persistent `ST` Monad

The Persistent `ST` Monad transformer