Control.Comonad.Context

The state-in-context comonad and comonad transformer

Documentation

module Control.Comonad

class Comonad w => ComonadContext s w | w -> s where

Methods

getC :: w a -> s

modifyC :: (s -> s) -> w a -> a

Instances

ComonadContext s (Context s)

Comonad w => ComonadContext s (ContextT s w)

putC :: ComonadContext s w => s -> w a -> a

experiment :: (ComonadContext s w, Functor f) => f (s -> s) -> w a -> f a

data Context s a

Constructors

Context (s -> a) s

Instances

ComonadContext s (Context s)

Functor (Context s)

Copointed (Context s)

Comonad (Context s)

runContext :: (Context s s -> Context s b) -> s -> (b, s)

newtype ContextT s w a

Constructors

ContextT

Fields

runContextT :: (w s -> a, w s)

Instances

Comonad w => ComonadContext s (ContextT s w)

Functor (ContextT b f)

Copointed (ContextT b w)

Comonad w => Comonad (ContextT b w)