Safe Haskell	Safe
Language	Haskell98

Control.Proxy.Trans.Writer

Contents

WriterP
Writer operations

Description

This module provides the proxy transformer equivalent of WriterT.

This module is even stricter than Control.Monad.Trans.Writer.Strict by being strict in the accumulated monoid.

The underlying implementation uses the state monad to avoid quadratic blowup from left-associative binds.

Synopsis

WriterP

newtype WriterP w p a' a b' b m r Source #

The strict Writer proxy transformer

Constructors

WriterP
Fields unWriterP :: w -> p a' a b' b m (r, w)

Instances

ProxyTrans (WriterP w) Source #
Methods liftP :: (Monad m, Proxy p) => p a' a b' b m r -> WriterP w p a' a b' b m r Source #
PFunctor (WriterP w) Source #
Methods hoistP :: (Monad m, Proxy p1) => (forall r1. p1 a' a b' b m r1 -> p2 a' a b' b n r1) -> WriterP w p1 a' a b' b m r2 -> WriterP w p2 a' a b' b n r2 Source #
MonadIOP p => MonadIOP (WriterP w p) Source #
Methods liftIO_P :: MonadIO m => IO r -> WriterP w p a' a b' b m r Source #
MonadPlusP p => MonadPlusP (WriterP w p) Source #
Methods mzero_P :: Monad m => WriterP w p a' a b' b m r Source # mplus_P :: Monad m => WriterP w p a' a b' b m r -> WriterP w p a' a b' b m r -> WriterP w p a' a b' b m r Source #
Proxy p => Proxy (WriterP w p) Source #
Methods request :: Monad m => a' -> WriterP w p a' a b' b m a Source # respond :: Monad m => b -> WriterP w p a' a b' b m b' Source # (>->) :: Monad m => (b' -> WriterP w p a' a b' b m r) -> (c' -> WriterP w p b' b c' c m r) -> c' -> WriterP w p a' a c' c m r Source # (>~>) :: Monad m => (a -> WriterP w p a' a b' b m r) -> (b -> WriterP w p b' b c' c m r) -> a -> WriterP w p a' a c' c m r Source # return_P :: Monad m => r -> WriterP w p a' a b' b m r Source # (?>=) :: Monad m => WriterP w p a' a b' b m r -> (r -> WriterP w p a' a b' b m r') -> WriterP w p a' a b' b m r' Source # lift_P :: Monad m => m r -> WriterP w p a' a b' b m r Source # hoist_P :: Monad m => (forall r. m r -> n r) -> WriterP w p a' a b' b m r' -> WriterP w p a' a b' b n r' Source #
Proxy p => MonadTrans (WriterP w p a' a b' b) Source #
Methods lift :: Monad m => m a -> WriterP w p a' a b' b m a #
Proxy p => MFunctor (WriterP w p a' a b' b) Source #
Methods hoist :: Monad m => (forall c. m c -> n c) -> WriterP w p a' a b' b m b -> WriterP w p a' a b' b n b Source #
(Proxy p, Monad m) => Monad (WriterP w p a' a b' b m) Source #
Methods (>>=) :: WriterP w p a' a b' b m a -> (a -> WriterP w p a' a b' b m b) -> WriterP w p a' a b' b m b # (>>) :: WriterP w p a' a b' b m a -> WriterP w p a' a b' b m b -> WriterP w p a' a b' b m b # return :: a -> WriterP w p a' a b' b m a # fail :: String -> WriterP w p a' a b' b m a #
(Proxy p, Monad m) => Functor (WriterP w p a' a b' b m) Source #
Methods fmap :: (a -> b) -> WriterP w p a' a b' b m a -> WriterP w p a' a b' b m b # (<$) :: a -> WriterP w p a' a b' b m b -> WriterP w p a' a b' b m a #
(Proxy p, Monad m) => Applicative (WriterP w p a' a b' b m) Source #
Methods pure :: a -> WriterP w p a' a b' b m a # (<>) :: WriterP w p a' a b' b m (a -> b) -> WriterP w p a' a b' b m a -> WriterP w p a' a b' b m b # (>) :: WriterP w p a' a b' b m a -> WriterP w p a' a b' b m b -> WriterP w p a' a b' b m b # (<*) :: WriterP w p a' a b' b m a -> WriterP w p a' a b' b m b -> WriterP w p a' a b' b m a #
(MonadIOP p, MonadIO m) => MonadIO (WriterP w p a' a b' b m) Source #
Methods liftIO :: IO a -> WriterP w p a' a b' b m a #
(MonadPlusP p, Monad m) => Alternative (WriterP w p a' a b' b m) Source #
Methods empty :: WriterP w p a' a b' b m a # (<\|>) :: WriterP w p a' a b' b m a -> WriterP w p a' a b' b m a -> WriterP w p a' a b' b m a # some :: WriterP w p a' a b' b m a -> WriterP w p a' a b' b m [a] # many :: WriterP w p a' a b' b m a -> WriterP w p a' a b' b m [a] #
(MonadPlusP p, Monad m) => MonadPlus (WriterP w p a' a b' b m) Source #
Methods mzero :: WriterP w p a' a b' b m a # mplus :: WriterP w p a' a b' b m a -> WriterP w p a' a b' b m a -> WriterP w p a' a b' b m a #

runWriterP :: Monoid w => WriterP w p a' a b' b m r -> p a' a b' b m (r, w) Source #

Run a WriterP computation, producing the final result and monoid

runWriterK :: Monoid w => (q -> WriterP w p a' a b' b m r) -> q -> p a' a b' b m (r, w) Source #

Run a WriterP 'K'leisli arrow, producing the final result and monoid

execWriterP :: (Proxy p, Monad m, Monoid w) => WriterP w p a' a b' b m r -> p a' a b' b m w Source #

Evaluate a WriterP computation, but discard the final result

execWriterK :: (Proxy p, Monad m, Monoid w) => (q -> WriterP w p a' a b' b m r) -> q -> p a' a b' b m w Source #

Evaluate a WriterP 'K'leisli arrow, but discard the final result

Writer operations

tell :: (Proxy p, Monad m, Monoid w) => w -> WriterP w p a' a b' b m () Source #

Add a value to the monoid

censor :: (Proxy p, Monad m, Monoid w) => (w -> w) -> WriterP w p a' a b' b m r -> WriterP w p a' a b' b m r Source #

Modify the result of a writer computation