Safe Haskell	Safe
Language	Haskell98

Control.Proxy.Trans

Contents

Proxy Transformers

Description

You can define your own extensions to the Proxy type by writing your own "proxy transformers". Proxy transformers are monad transformers that correctly lift Proxy composition from the base monad. Stack multiple proxy transformers to chain features together.

Synopsis

Proxy Transformers

class ProxyTrans t where Source #

mapP defines a functor that preserves Proxy composition and Kleisli composition.

Laws:

Functor between Proxy categories

mapP (f <-< g) = mapP f <-< mapP g
mapP idT = idT

Functor between Kleisli categories

mapP (f <=< g) = mapP f <=< mapP g
mapP return = return

Minimal complete definition: mapP or liftP. Defining liftP is more efficient.

Methods

liftP :: (Monad (p b c d e m), Channel p) => p b c d e m r -> t p b c d e m r Source #

mapP :: (Monad (p b c d e m), Channel p) => (a -> p b c d e m r) -> a -> t p b c d e m r Source #

Instances

ProxyTrans IdentityP Source #
Methods liftP :: (Monad (p b c d e m), Channel p) => p b c d e m r -> IdentityP p b c d e m r Source # mapP :: (Monad (p b c d e m), Channel p) => (a -> p b c d e m r) -> a -> IdentityP p b c d e m r Source #
ProxyTrans MaybeP Source #
Methods liftP :: (Monad (p b c d e m), Channel p) => p b c d e m r -> MaybeP p b c d e m r Source # mapP :: (Monad (p b c d e m), Channel p) => (a -> p b c d e m r) -> a -> MaybeP p b c d e m r Source #
ProxyTrans (EitherP e) Source #
Methods liftP :: (Monad (p b c d e m), Channel p) => p b c d e m r -> EitherP e p b c d e m r Source # mapP :: (Monad (p b c d e m), Channel p) => (a -> p b c d e m r) -> a -> EitherP e p b c d e m r Source #
ProxyTrans (ReaderP i) Source #
Methods liftP :: (Monad (p b c d e m), Channel p) => p b c d e m r -> ReaderP i p b c d e m r Source # mapP :: (Monad (p b c d e m), Channel p) => (a -> p b c d e m r) -> a -> ReaderP i p b c d e m r Source #
ProxyTrans (StateP s) Source #
Methods liftP :: (Monad (p b c d e m), Channel p) => p b c d e m r -> StateP s p b c d e m r Source # mapP :: (Monad (p b c d e m), Channel p) => (a -> p b c d e m r) -> a -> StateP s p b c d e m r Source #
Monoid w => ProxyTrans (WriterP w) Source #
Methods liftP :: (Monad (p b c d e m), Channel p) => p b c d e m r -> WriterP w p b c d e m r Source # mapP :: (Monad (p b c d e m), Channel p) => (a -> p b c d e m r) -> a -> WriterP w p b c d e m r Source #