Safe Haskell	Safe
Language	Haskell2010

Control.Monad.Trans.Lift.Listen

Description

Lifting the listen operation.

Synopsis

Documentation

class MonadTrans t => LiftListen t where Source #

The class of monad transformers capable of lifting listen.

Minimal complete definition

liftListen

Methods

liftListen :: Monad m => Listen w m (StT t a) -> Listen w (t m) a Source #

Lift the listen operation. Should satisfy the uniformity property

```
lift . liftListen = liftListen . lift
```

Instances

LiftListen MaybeT Source #
Methods liftListen :: Monad m => Listen w m (StT MaybeT a) -> Listen w (MaybeT m) a Source #
Monoid w' => LiftListen (WriterT w') Source #
Methods liftListen :: Monad m => Listen w m (StT (WriterT w') a) -> Listen w (WriterT w' m) a Source #
Monoid w' => LiftListen (WriterT w') Source #
Methods liftListen :: Monad m => Listen w m (StT (WriterT w') a) -> Listen w (WriterT w' m) a Source #
LiftListen (StateT s) Source #
Methods liftListen :: Monad m => Listen w m (StT (StateT s) a) -> Listen w (StateT s m) a Source #
LiftListen (StateT s) Source #
Methods liftListen :: Monad m => Listen w m (StT (StateT s) a) -> Listen w (StateT s m) a Source #
LiftListen (IdentityT *) Source #
Methods liftListen :: Monad m => Listen w m (StT (IdentityT ) a) -> Listen w (IdentityT m) a Source #
LiftListen (ExceptT e) Source #
Methods liftListen :: Monad m => Listen w m (StT (ExceptT e) a) -> Listen w (ExceptT e m) a Source #
Monoid w' => LiftListen (WriterT w') Source #
Methods liftListen :: Monad m => Listen w m (StT (WriterT w') a) -> Listen w (WriterT w' m) a Source #
LiftListen (ReaderT * r) Source #
Methods liftListen :: Monad m => Listen w m (StT (ReaderT * r) a) -> Listen w (ReaderT * r m) a Source #
Monoid w' => LiftListen (RWST r w' s) Source #
Methods liftListen :: Monad m => Listen w m (StT (RWST r w' s) a) -> Listen w (RWST r w' s m) a Source #
Monoid w' => LiftListen (RWST r w' s) Source #
Methods liftListen :: Monad m => Listen w m (StT (RWST r w' s) a) -> Listen w (RWST r w' s m) a Source #
Monoid w' => LiftListen (RWST r w' s) Source #
Methods liftListen :: Monad m => Listen w m (StT (RWST r w' s) a) -> Listen w (RWST r w' s m) a Source #

type Listen w m a = m a -> m (a, w) #

Signature of the listen operation, introduced in Control.Monad.Trans.Writer. Any lifting function liftListen should satisfy

```
lift . liftListen = liftListen . lift
```

defaultLiftListen Source #

Arguments

:: (Monad m, LiftListen n)
=> (forall x. n m x -> t m x)	Monad constructor
-> (forall o x. t o x -> n o x)	Monad deconstructor
-> Listen w m (StT n a)
-> Listen w (t m) a

Default definition for the liftListen method.

module Control.Monad.Trans.Class