Copyright | (C) 2015 KONISHI Yohsuke, (c) Andy Gill 2001, (c) Oregon Graduate Institute of Science and Technology, 2001 |
---|---|
License | BSD-style (see the file LICENSE) |
Maintainer | ocean0yohsuke@gmail.com |
Stability | experimental |
Portability | --- |
Safe Haskell | Safe |
Language | Haskell2010 |
This module extended RWS Monad in mtl(monad-transformer-library).
- module Control.Monad.RWS
- class Monad m => MonadReader r m | m -> r where
- class (Monoid w, Monad m) => MonadWriter w m | m -> w where
- class Monad m => MonadState s m | m -> s where
- newtype RWST2 r w s m1 m2 a = RWST2 {
- runRWST2 :: r -> s -> m1 (m2 (a, s, w))
- rwsT2 :: (Monad m1, Monad2 m2) => (r -> s -> (a, s, w)) -> RWST2 r w s m1 m2 a
- evalRWST2 :: (Monad m1, Monad2 m2) => RWST2 r w s m1 m2 a -> r -> s -> m1 (m2 (a, w))
- execRWST2 :: (Monad m1, Monad2 m2) => RWST2 r w s m1 m2 a -> r -> s -> m1 (m2 (s, w))
- mapRWST2 :: (m1 (m2 (a, s, w)) -> n1 (n2 (b, s, w'))) -> RWST2 r w s m1 m2 a -> RWST2 r w' s n1 n2 b
- withRWST2 :: (r' -> s -> (r, s)) -> RWST2 r w s m1 m2 a -> RWST2 r' w s m1 m2 a
- liftCatch2 :: Catch2 e m1 m2 (a, s, w) -> Catch e (RWST2 r w s m1 m2) a
- newtype RWST3 r w s m1 m2 m3 a = RWST3 {
- runRWST3 :: r -> s -> m1 (m2 (m3 (a, s, w)))
- rwsT3 :: (Monad m1, Monad2 m2, Monad3 m3) => (r -> s -> (a, s, w)) -> RWST3 r w s m1 m2 m3 a
- evalRWST3 :: (Monad m1, Monad2 m2, Monad3 m3) => RWST3 r w s m1 m2 m3 a -> r -> s -> m1 (m2 (m3 (a, w)))
- execRWST3 :: (Monad m1, Monad2 m2, Monad3 m3) => RWST3 r w s m1 m2 m3 a -> r -> s -> m1 (m2 (m3 (s, w)))
- mapRWST3 :: (m1 (m2 (m3 (a, s, w))) -> n1 (n2 (n3 (b, s, w')))) -> RWST3 r w s m1 m2 m3 a -> RWST3 r w' s n1 n2 n3 b
- withRWST3 :: (r' -> s -> (r, s)) -> RWST3 r w s m1 m2 m3 a -> RWST3 r' w s m1 m2 m3 a
- liftCatch3 :: Catch3 e m1 m2 m3 (a, s, w) -> Catch e (RWST3 r w s m1 m2 m3) a
Documentation
module Control.Monad.RWS
class Monad m => MonadReader r m | m -> r where
See examples in Control.Monad.Reader.
Note, the partially applied function type (->) r
is a simple reader monad.
See the instance
declaration below.
ask :: m r
Retrieves the monad environment.
:: (r -> r) | The function to modify the environment. |
-> m a |
|
-> m a |
Executes a computation in a modified environment.
:: (r -> a) | The selector function to apply to the environment. |
-> m a |
Retrieves a function of the current environment.
MonadReader r m => MonadReader r (MaybeT m) | |
MonadReader r m => MonadReader r (ListT m) | |
MonadReader r m => MonadReader r (IdentityT m) | |
MonadReader r ((->) r) | |
(Monoid w, MonadReader r m) => MonadReader r (WriterT w m) | |
(Monoid w, MonadReader r m) => MonadReader r (WriterT w m) | |
MonadReader r m => MonadReader r (StateT s m) | |
MonadReader r m => MonadReader r (StateT s m) | |
Monad m => MonadReader r (ReaderT r m) | |
MonadReader r m => MonadReader r (ExceptT e m) | |
(Error e, MonadReader r m) => MonadReader r (ErrorT e m) | |
MonadReader r' m => MonadReader r' (ContT r m) | |
(Monad m1, Monad2 m2) => MonadReader r (ReaderT2 r m1 m2) | |
(Monad m, Monoid w) => MonadReader r (RWST r w s m) | |
(Monad m, Monoid w) => MonadReader r (RWST r w s m) | |
(Monad m1, Monad2 m2, Monad3 m3) => MonadReader r (ReaderT3 r m1 m2 m3) | |
(Monoid w, Monad m1, Monad2 m2) => MonadReader r (RWST2 r w s m1 m2) | |
(Monoid w, Monad m1, Monad2 m2, Monad3 m3) => MonadReader r (RWST3 r w s m1 m2 m3) |
class (Monoid w, Monad m) => MonadWriter w m | m -> w where
writer :: (a, w) -> m a
embeds a simple writer action.writer
(a,w)
tell :: w -> m ()
is an action that produces the output tell
ww
.
listen :: m a -> m (a, w)
is an action that executes the action listen
mm
and adds
its output to the value of the computation.
pass :: m (a, w -> w) -> m a
is an action that executes the action pass
mm
, which
returns a value and a function, and returns the value, applying
the function to the output.
MonadWriter w m => MonadWriter w (MaybeT m) | |
MonadWriter w m => MonadWriter w (IdentityT m) | |
(Monoid w, Monad m) => MonadWriter w (WriterT w m) | |
(Monoid w, Monad m) => MonadWriter w (WriterT w m) | |
MonadWriter w m => MonadWriter w (StateT s m) | |
MonadWriter w m => MonadWriter w (StateT s m) | |
MonadWriter w m => MonadWriter w (ReaderT r m) | |
MonadWriter w m => MonadWriter w (ExceptT e m) | |
(Error e, MonadWriter w m) => MonadWriter w (ErrorT e m) | |
(Monoid w, Monad m) => MonadWriter w (RWST r w s m) | |
(Monoid w, Monad m) => MonadWriter w (RWST r w s m) | |
(Monoid w, Monad m1, Monad2 m2) => MonadWriter w (RWST2 r w s m1 m2) | |
(Monoid w, Monad m1, Monad2 m2, Monad3 m3) => MonadWriter w (RWST3 r w s m1 m2 m3) |
class Monad m => MonadState s m | m -> s where
Minimal definition is either both of get
and put
or just state
get :: m s
Return the state from the internals of the monad.
put :: s -> m ()
Replace the state inside the monad.
state :: (s -> (a, s)) -> m a
Embed a simple state action into the monad.
MonadState s m => MonadState s (MaybeT m) | |
MonadState s m => MonadState s (ListT m) | |
MonadState s m => MonadState s (IdentityT m) | |
(Monoid w, MonadState s m) => MonadState s (WriterT w m) | |
(Monoid w, MonadState s m) => MonadState s (WriterT w m) | |
Monad m => MonadState s (StateT s m) | |
Monad m => MonadState s (StateT s m) | |
MonadState s m => MonadState s (ReaderT r m) | |
MonadState s m => MonadState s (ExceptT e m) | |
(Error e, MonadState s m) => MonadState s (ErrorT e m) | |
MonadState s m => MonadState s (ContT r m) | |
(Monad m1, Monad2 m2) => MonadState s (StateT2 s m1 m2) | |
(Monad m, Monoid w) => MonadState s (RWST r w s m) | |
(Monad m, Monoid w) => MonadState s (RWST r w s m) | |
(Monad m1, Monad2 m2, Monad3 m3) => MonadState s (StateT3 s m1 m2 m3) | |
(Monoid w, Monad m1, Monad2 m2) => MonadState s (RWST2 r w s m1 m2) | |
(Monoid w, Monad m1, Monad2 m2, Monad3 m3) => MonadState s (RWST3 r w s m1 m2 m3) |
Level-2
newtype RWST2 r w s m1 m2 a Source
(Monoid w, Monad m1, Monad2 m2) => MonadReader r (RWST2 r w s m1 m2) Source | |
(Monoid w, Monad m1, Monad2 m2) => MonadState s (RWST2 r w s m1 m2) Source | |
(Monoid w, Monad m1, Monad2 m2) => MonadWriter w (RWST2 r w s m1 m2) Source | |
Monoid w => MonadTransCover2 (RWST2 r w s) Source | |
Monoid w => MonadTransFold2 (RWST2 r w s) Source | |
Monoid w => MonadTrans2Down (RWST2 r w s) Source | |
Monoid w => MonadTrans2 (RWST2 r w s) Source | |
(Monoid w, Monad m1, Monad2 m2) => Monad (RWST2 r w s m1 m2) Source | |
(Functor m1, Functor m2) => Functor (RWST2 r w s m1 m2) Source | |
(Monoid w, Monad m1, Monad2 m2) => Applicative (RWST2 r w s m1 m2) Source | |
(Monoid w, MonadPlus m1, MonadPlus m2, Monad m1, Monad2 m2) => Alternative (RWST2 r w s m1 m2) Source | |
(Monoid w, MonadPlus m1, MonadPlus m2, Monad m1, Monad2 m2) => MonadPlus (RWST2 r w s m1 m2) Source | |
(Monoid w, MonadIO m1, Monad m1, Monad2 m2) => MonadIO (RWST2 r w s m1 m2) Source | |
type Trans2Down (RWST2 r w s) = RWST r w s Source |
mapRWST2 :: (m1 (m2 (a, s, w)) -> n1 (n2 (b, s, w'))) -> RWST2 r w s m1 m2 a -> RWST2 r w' s n1 n2 b Source
lift function
liftCatch2 :: Catch2 e m1 m2 (a, s, w) -> Catch e (RWST2 r w s m1 m2) a Source
Level-3
newtype RWST3 r w s m1 m2 m3 a Source
evalRWST3 :: (Monad m1, Monad2 m2, Monad3 m3) => RWST3 r w s m1 m2 m3 a -> r -> s -> m1 (m2 (m3 (a, w))) Source
execRWST3 :: (Monad m1, Monad2 m2, Monad3 m3) => RWST3 r w s m1 m2 m3 a -> r -> s -> m1 (m2 (m3 (s, w))) Source
mapRWST3 :: (m1 (m2 (m3 (a, s, w))) -> n1 (n2 (n3 (b, s, w')))) -> RWST3 r w s m1 m2 m3 a -> RWST3 r w' s n1 n2 n3 b Source
lift function
liftCatch3 :: Catch3 e m1 m2 m3 (a, s, w) -> Catch e (RWST3 r w s m1 m2 m3) a Source