 | monads-fd-0.1.0.1: Monad classes, using functional dependencies | Contents | Index |
|
| Control.Monad.RWS.Lazy | | Portability | non-portable (multi-param classes, functional dependencies) | | Stability | experimental | | Maintainer | libraries@haskell.org |
|
|
|
|
|
| Description |
Lazy RWS monad.
Inspired by the paper
/Functional Programming with Overloading and
Higher-Order Polymorphism/,
Mark P Jones (http://web.cecs.pdx.edu/~mpj/)
Advanced School of Functional Programming, 1995.
|
|
| Synopsis |
|
| type RWS r w s = RWST r w s Identity | | | runRWS :: RWS r w s a -> r -> s -> (a, s, w) | | | evalRWS :: RWS r w s a -> r -> s -> (a, w) | | | execRWS :: RWS r w s a -> r -> s -> (s, w) | | | mapRWS :: ((a, s, w) -> (b, s, w')) -> RWS r w s a -> RWS r w' s b | | | withRWS :: (r' -> s -> (r, s)) -> RWS r w s a -> RWS r' w s a | | | newtype RWST r w s m a = RWST {} | | | evalRWST :: Monad m => RWST r w s m a -> r -> s -> m (a, w) | | | execRWST :: Monad m => RWST r w s m a -> r -> s -> m (s, w) | | | mapRWST :: (m (a, s, w) -> n (b, s, w')) -> RWST r w s m a -> RWST r w' s n b | | | withRWST :: (r' -> s -> (r, s)) -> RWST r w s m a -> RWST r' w s m a | | | module Control.Monad.RWS.Class | | | module Control.Monad | | | module Control.Monad.Fix | | | module Control.Monad.Trans | | | module Data.Monoid |
|
|
|
| The RWS monad
|
|
| type RWS r w s = RWST r w s Identity |
| A monad containing an environment of type r, output of type w
and an updatable state of type s.
|
|
| runRWS :: RWS r w s a -> r -> s -> (a, s, w) |
| Unwrap an RWS computation as a function.
(The inverse of rws.)
|
|
| evalRWS :: RWS r w s a -> r -> s -> (a, w) |
|
| execRWS :: RWS r w s a -> r -> s -> (s, w) |
|
| mapRWS :: ((a, s, w) -> (b, s, w')) -> RWS r w s a -> RWS r w' s b |
|
| withRWS :: (r' -> s -> (r, s)) -> RWS r w s a -> RWS r' w s a |
|
| The RWST monad transformer
|
|
| newtype RWST r w s m a |
| A monad transformer adding reading an environment of type r,
collecting an output of type w and updating a state of type s
to an inner monad m.
| | Constructors | | RWST | | | runRWST :: r -> s -> m (a, s, w) | |
|
| Instances | | (Monoid w, Monad m) => MonadRWS r w s (RWST r w s m) | | | (Monoid w, Monad m) => MonadWriter w (RWST r w s m) | | | (Monad m, Monoid w) => MonadState s (RWST r w s m) | | | (Monad m, Monoid w) => MonadReader r (RWST r w s m) | | | (Monoid w, MonadError e m) => MonadError e (RWST r w s m) | | | Monoid w => MonadTrans (RWST r w s) | | | (Monoid w, Monad m) => Monad (RWST r w s m) | | | Functor m => Functor (RWST r w s m) | | | (Monoid w, MonadFix m) => MonadFix (RWST r w s m) | | | (Monoid w, MonadPlus m) => MonadPlus (RWST r w s m) | | | (Monoid w, Functor m, Monad m) => Applicative (RWST r w s m) | | | (Monoid w, Functor m, MonadPlus m) => Alternative (RWST r w s m) | | | (Monoid w, MonadIO m) => MonadIO (RWST r w s m) | | | (Monoid w, MonadCont m) => MonadCont (RWST r w s m) | |
|
|
|
| evalRWST :: Monad m => RWST r w s m a -> r -> s -> m (a, w) |
|
| execRWST :: Monad m => RWST r w s m a -> r -> s -> m (s, w) |
|
| mapRWST :: (m (a, s, w) -> n (b, s, w')) -> RWST r w s m a -> RWST r w' s n b |
|
| withRWST :: (r' -> s -> (r, s)) -> RWST r w s m a -> RWST r' w s m a |
|
| Lazy Reader-writer-state monads
|
|
| module Control.Monad.RWS.Class |
|
| module Control.Monad |
|
| module Control.Monad.Fix |
|
| module Control.Monad.Trans |
|
| module Data.Monoid |
|
| Produced by Haddock version 2.7.2 |