Copyright	(c) Roman Leshchinskiy 2009
License	BSD-style
Maintainer	Roman Leshchinskiy <rl@cse.unsw.edu.au>
Portability	non-portable
Safe Haskell	None
Language	Haskell2010

Control.Monad.Primitive

Description

Primitive state-transformer monads

Synopsis

class Monad m => PrimMonad m where
- type PrimState m
- primitive :: (State# (PrimState m) -> (#State# (PrimState m), a#)) -> m a
data RealWorld :: Type
primitive_ :: PrimMonad m => (State# (PrimState m) -> State# (PrimState m)) -> m ()
class PrimMonad m => PrimBase m where
- internal :: m a -> State# (PrimState m) -> (#State# (PrimState m), a#)
liftPrim :: (PrimBase m1, PrimMonad m2, PrimState m1 ~ PrimState m2) => m1 a -> m2 a
primToPrim :: (PrimBase m1, PrimMonad m2, PrimState m1 ~ PrimState m2) => m1 a -> m2 a
primToIO :: (PrimBase m, PrimState m ~ RealWorld) => m a -> IO a
primToST :: PrimBase m => m a -> ST (PrimState m) a
ioToPrim :: (PrimMonad m, PrimState m ~ RealWorld) => IO a -> m a
stToPrim :: PrimMonad m => ST (PrimState m) a -> m a
unsafePrimToPrim :: (PrimBase m1, PrimMonad m2) => m1 a -> m2 a
unsafePrimToIO :: PrimBase m => m a -> IO a
unsafePrimToST :: PrimBase m => m a -> ST s a
unsafeIOToPrim :: PrimMonad m => IO a -> m a
unsafeSTToPrim :: PrimMonad m => ST s a -> m a
unsafeInlinePrim :: PrimBase m => m a -> a
unsafeInlineIO :: IO a -> a
unsafeInlineST :: ST s a -> a
touch :: PrimMonad m => a -> m ()
evalPrim :: forall a m. PrimMonad m => a -> m a
unsafeInterleave :: PrimBase m => m a -> m a
unsafeDupableInterleave :: PrimBase m => m a -> m a
noDuplicate :: PrimMonad m => m ()

Documentation

class Monad m => PrimMonad m where #

Class of monads which can perform primitive state-transformer actions

Associated Types

type PrimState m #

State token type

Methods

primitive :: (State# (PrimState m) -> (#State# (PrimState m), a#)) -> m a #

Execute a primitive operation

Instances

PrimMonad IO #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState IO :: Type # Methods primitive :: (State# (PrimState IO) -> (#State# (PrimState IO), a#)) -> IO a #
PrimMonad (ST s) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (ST s) :: Type # Methods primitive :: (State# (PrimState (ST s)) -> (#State# (PrimState (ST s)), a#)) -> ST s a #
PrimMonad m => PrimMonad (MaybeT m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (MaybeT m) :: Type # Methods primitive :: (State# (PrimState (MaybeT m)) -> (#State# (PrimState (MaybeT m)), a#)) -> MaybeT m a #
PrimMonad m => PrimMonad (ListT m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (ListT m) :: Type # Methods primitive :: (State# (PrimState (ListT m)) -> (#State# (PrimState (ListT m)), a#)) -> ListT m a #
(Monoid w, PrimMonad m) => PrimMonad (WriterT w m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (WriterT w m) :: Type # Methods primitive :: (State# (PrimState (WriterT w m)) -> (#State# (PrimState (WriterT w m)), a#)) -> WriterT w m a #
(Monoid w, PrimMonad m) => PrimMonad (AccumT w m) #	Since: 0.6.3.0
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (AccumT w m) :: Type # Methods primitive :: (State# (PrimState (AccumT w m)) -> (#State# (PrimState (AccumT w m)), a#)) -> AccumT w m a #
(Monoid w, PrimMonad m) => PrimMonad (WriterT w m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (WriterT w m) :: Type # Methods primitive :: (State# (PrimState (WriterT w m)) -> (#State# (PrimState (WriterT w m)), a#)) -> WriterT w m a #
(Monoid w, PrimMonad m) => PrimMonad (WriterT w m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (WriterT w m) :: Type # Methods primitive :: (State# (PrimState (WriterT w m)) -> (#State# (PrimState (WriterT w m)), a#)) -> WriterT w m a #
PrimMonad m => PrimMonad (StateT s m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (StateT s m) :: Type # Methods primitive :: (State# (PrimState (StateT s m)) -> (#State# (PrimState (StateT s m)), a#)) -> StateT s m a #
PrimMonad m => PrimMonad (StateT s m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (StateT s m) :: Type # Methods primitive :: (State# (PrimState (StateT s m)) -> (#State# (PrimState (StateT s m)), a#)) -> StateT s m a #
PrimMonad m => PrimMonad (SelectT r m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (SelectT r m) :: Type # Methods primitive :: (State# (PrimState (SelectT r m)) -> (#State# (PrimState (SelectT r m)), a#)) -> SelectT r m a #
PrimMonad m => PrimMonad (ReaderT r m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (ReaderT r m) :: Type # Methods primitive :: (State# (PrimState (ReaderT r m)) -> (#State# (PrimState (ReaderT r m)), a#)) -> ReaderT r m a #
PrimMonad m => PrimMonad (IdentityT m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (IdentityT m) :: Type # Methods primitive :: (State# (PrimState (IdentityT m)) -> (#State# (PrimState (IdentityT m)), a#)) -> IdentityT m a #
PrimMonad m => PrimMonad (ExceptT e m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (ExceptT e m) :: Type # Methods primitive :: (State# (PrimState (ExceptT e m)) -> (#State# (PrimState (ExceptT e m)), a#)) -> ExceptT e m a #
(Error e, PrimMonad m) => PrimMonad (ErrorT e m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (ErrorT e m) :: Type # Methods primitive :: (State# (PrimState (ErrorT e m)) -> (#State# (PrimState (ErrorT e m)), a#)) -> ErrorT e m a #
PrimMonad m => PrimMonad (ContT r m) #	Since: 0.6.3.0
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (ContT r m) :: Type # Methods primitive :: (State# (PrimState (ContT r m)) -> (#State# (PrimState (ContT r m)), a#)) -> ContT r m a #
(Monoid w, PrimMonad m) => PrimMonad (RWST r w s m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (RWST r w s m) :: Type # Methods primitive :: (State# (PrimState (RWST r w s m)) -> (#State# (PrimState (RWST r w s m)), a#)) -> RWST r w s m a #
(Monoid w, PrimMonad m) => PrimMonad (RWST r w s m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (RWST r w s m) :: Type # Methods primitive :: (State# (PrimState (RWST r w s m)) -> (#State# (PrimState (RWST r w s m)), a#)) -> RWST r w s m a #
(Monoid w, PrimMonad m) => PrimMonad (RWST r w s m) #
Instance details Defined in Control.Monad.Primitive Associated Types type PrimState (RWST r w s m) :: Type # Methods primitive :: (State# (PrimState (RWST r w s m)) -> (#State# (PrimState (RWST r w s m)), a#)) -> RWST r w s m a #

data RealWorld :: Type #

RealWorld is deeply magical. It is primitive, but it is not unlifted (hence ptrArg). We never manipulate values of type RealWorld; it's only used in the type system, to parameterise State#.

primitive_ :: PrimMonad m => (State# (PrimState m) -> State# (PrimState m)) -> m () #

Execute a primitive operation with no result

class PrimMonad m => PrimBase m where #

Class of primitive monads for state-transformer actions.

Unlike PrimMonad, this typeclass requires that the Monad be fully expressed as a state transformer, therefore disallowing other monad transformers on top of the base IO or ST.

Since: 0.6.0.0

Methods

internal :: m a -> State# (PrimState m) -> (#State# (PrimState m), a#) #

Expose the internal structure of the monad

Instances

PrimBase IO #
Instance details Defined in Control.Monad.Primitive Methods internal :: IO a -> State# (PrimState IO) -> (#State# (PrimState IO), a#) #
PrimBase (ST s) #
Instance details Defined in Control.Monad.Primitive Methods internal :: ST s a -> State# (PrimState (ST s)) -> (#State# (PrimState (ST s)), a#) #
PrimBase m => PrimBase (IdentityT m) #	Since: 0.6.2.0
Instance details Defined in Control.Monad.Primitive Methods internal :: IdentityT m a -> State# (PrimState (IdentityT m)) -> (#State# (PrimState (IdentityT m)), a#) #

liftPrim :: (PrimBase m1, PrimMonad m2, PrimState m1 ~ PrimState m2) => m1 a -> m2 a #

Lifts a PrimBase into another PrimMonad with the same underlying state token type.

primToPrim :: (PrimBase m1, PrimMonad m2, PrimState m1 ~ PrimState m2) => m1 a -> m2 a #

Convert a PrimBase to another monad with the same state token.

primToIO :: (PrimBase m, PrimState m ~ RealWorld) => m a -> IO a #

Convert a PrimBase with a RealWorld state token to IO

primToST :: PrimBase m => m a -> ST (PrimState m) a #

Convert a PrimBase to ST

ioToPrim :: (PrimMonad m, PrimState m ~ RealWorld) => IO a -> m a #

Convert an IO action to a PrimMonad.

Since: 0.6.2.0

stToPrim :: PrimMonad m => ST (PrimState m) a -> m a #

Convert an ST action to a PrimMonad.

Since: 0.6.2.0

unsafePrimToPrim :: (PrimBase m1, PrimMonad m2) => m1 a -> m2 a #

Convert a PrimBase to another monad with a possibly different state token. This operation is highly unsafe!

unsafePrimToIO :: PrimBase m => m a -> IO a #

Convert any PrimBase to IO. This operation is highly unsafe!

unsafePrimToST :: PrimBase m => m a -> ST s a #

Convert any PrimBase to ST with an arbitrary state token. This operation is highly unsafe!

unsafeIOToPrim :: PrimMonad m => IO a -> m a #

Convert an IO action to any PrimMonad. This operation is highly unsafe!

Since: 0.6.2.0

unsafeSTToPrim :: PrimMonad m => ST s a -> m a #

Convert an ST action with an arbitrary state token to any PrimMonad. This operation is highly unsafe!

Since: 0.6.2.0

unsafeInlinePrim :: PrimBase m => m a -> a #

unsafeInlineIO :: IO a -> a #

unsafeInlineST :: ST s a -> a #

touch :: PrimMonad m => a -> m () #

evalPrim :: forall a m. PrimMonad m => a -> m a #

Create an action to force a value; generalizes evaluate

Since: 0.6.2.0

unsafeInterleave :: PrimBase m => m a -> m a #

unsafeDupableInterleave :: PrimBase m => m a -> m a #

noDuplicate :: PrimMonad m => m () #