Copyright	(c) Edward Kmett 2011 (c) Conal Elliott 2008
License	BSD3
Maintainer	ekmett@gmail.com
Stability	experimental
Safe Haskell	Safe-Inferred
Language	Haskell2010

Control.Monad.Representable.Reader

Contents

Representable functor monad
Monad Transformer

Description

Representable functors on Hask are all monads, because they are isomorphic to a Reader monad.

Synopsis

type Reader f = ReaderT f Identity
runReader :: Representable f => Reader f b -> Rep f -> b
newtype ReaderT f m b = ReaderT {
- getReaderT :: f (m b)
}
readerT :: Representable f => (Rep f -> m b) -> ReaderT f m b
runReaderT :: Representable f => ReaderT f m b -> Rep f -> m b
class Monad m => MonadReader r (m :: Type -> Type) | m -> r where
- ask :: m r
- local :: (r -> r) -> m a -> m a
- reader :: (r -> a) -> m a
module Data.Functor.Rep

Representable functor monad

type Reader f = ReaderT f Identity Source #

runReader :: Representable f => Reader f b -> Rep f -> b Source #

Monad Transformer

newtype ReaderT f m b Source #

Constructors

ReaderT

Fields

getReaderT :: f (m b)

Instances

Instances details

(Representable f, Monad m, Rep f ~ e) => MonadReader e (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

ask :: ReaderT f m e #

local :: (e -> e) -> ReaderT f m a -> ReaderT f m a #

reader :: (e -> a) -> ReaderT f m a #

(Representable f, MonadWriter w (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

writer :: (a, w) -> ReaderT f m a #

tell :: w -> ReaderT f m () #

listen :: ReaderT f m a -> ReaderT f m (a, w) #

pass :: ReaderT f m (a, w -> w) -> ReaderT f m a #

Representable f => MonadTrans (ReaderT f) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

lift :: Monad m => m a -> ReaderT f m a #

(Representable f, Representable m) => Representable (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Associated Types

type Rep (ReaderT f m) Source #

Methods

tabulate :: (Rep (ReaderT f m) -> a) -> ReaderT f m a Source #

index :: ReaderT f m a -> Rep (ReaderT f m) -> a Source #

(Representable f, MonadIO m) => MonadIO (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

liftIO :: IO a -> ReaderT f m a #

(Foldable f, Foldable m) => Foldable (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

fold :: Monoid m0 => ReaderT f m m0 -> m0 #

foldMap :: Monoid m0 => (a -> m0) -> ReaderT f m a -> m0 #

foldMap' :: Monoid m0 => (a -> m0) -> ReaderT f m a -> m0 #

foldr :: (a -> b -> b) -> b -> ReaderT f m a -> b #

foldr' :: (a -> b -> b) -> b -> ReaderT f m a -> b #

foldl :: (b -> a -> b) -> b -> ReaderT f m a -> b #

foldl' :: (b -> a -> b) -> b -> ReaderT f m a -> b #

foldr1 :: (a -> a -> a) -> ReaderT f m a -> a #

foldl1 :: (a -> a -> a) -> ReaderT f m a -> a #

toList :: ReaderT f m a -> [a] #

null :: ReaderT f m a -> Bool #

length :: ReaderT f m a -> Int #

elem :: Eq a => a -> ReaderT f m a -> Bool #

maximum :: Ord a => ReaderT f m a -> a #

minimum :: Ord a => ReaderT f m a -> a #

sum :: Num a => ReaderT f m a -> a #

product :: Num a => ReaderT f m a -> a #

(Foldable1 f, Foldable1 m) => Foldable1 (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

fold1 :: Semigroup m0 => ReaderT f m m0 -> m0 #

foldMap1 :: Semigroup m0 => (a -> m0) -> ReaderT f m a -> m0 #

foldMap1' :: Semigroup m0 => (a -> m0) -> ReaderT f m a -> m0 #

toNonEmpty :: ReaderT f m a -> NonEmpty a #

maximum :: Ord a => ReaderT f m a -> a #

minimum :: Ord a => ReaderT f m a -> a #

head :: ReaderT f m a -> a #

last :: ReaderT f m a -> a #

foldrMap1 :: (a -> b) -> (a -> b -> b) -> ReaderT f m a -> b #

foldlMap1' :: (a -> b) -> (b -> a -> b) -> ReaderT f m a -> b #

foldlMap1 :: (a -> b) -> (b -> a -> b) -> ReaderT f m a -> b #

foldrMap1' :: (a -> b) -> (a -> b -> b) -> ReaderT f m a -> b #

(Traversable f, Traversable m) => Traversable (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

traverse :: Applicative f0 => (a -> f0 b) -> ReaderT f m a -> f0 (ReaderT f m b) #

sequenceA :: Applicative f0 => ReaderT f m (f0 a) -> f0 (ReaderT f m a) #

mapM :: Monad m0 => (a -> m0 b) -> ReaderT f m a -> m0 (ReaderT f m b) #

sequence :: Monad m0 => ReaderT f m (m0 a) -> m0 (ReaderT f m a) #

(Representable f, Applicative m) => Applicative (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

pure :: a -> ReaderT f m a #

(<*>) :: ReaderT f m (a -> b) -> ReaderT f m a -> ReaderT f m b #

liftA2 :: (a -> b -> c) -> ReaderT f m a -> ReaderT f m b -> ReaderT f m c #

(*>) :: ReaderT f m a -> ReaderT f m b -> ReaderT f m b #

(<*) :: ReaderT f m a -> ReaderT f m b -> ReaderT f m a #

(Functor f, Functor m) => Functor (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

fmap :: (a -> b) -> ReaderT f m a -> ReaderT f m b #

(<$) :: a -> ReaderT f m b -> ReaderT f m a #

(Representable f, Monad m) => Monad (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

(>>=) :: ReaderT f m a -> (a -> ReaderT f m b) -> ReaderT f m b #

(>>) :: ReaderT f m a -> ReaderT f m b -> ReaderT f m b #

return :: a -> ReaderT f m a #

(Representable f, Representable m, Monoid (Rep f), Monoid (Rep m)) => Comonad (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

extract :: ReaderT f m a -> a #

duplicate :: ReaderT f m a -> ReaderT f m (ReaderT f m a) #

extend :: (ReaderT f m a -> b) -> ReaderT f m a -> ReaderT f m b #

(Representable f, Distributive m) => Distributive (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

distribute :: Functor f0 => f0 (ReaderT f m a) -> ReaderT f m (f0 a) #

collect :: Functor f0 => (a -> ReaderT f m b) -> f0 a -> ReaderT f m (f0 b) #

distributeM :: Monad m0 => m0 (ReaderT f m a) -> ReaderT f m (m0 a) #

collectM :: Monad m0 => (a -> ReaderT f m b) -> m0 a -> ReaderT f m (m0 b) #

(Representable f, Apply m) => Apply (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

(<.>) :: ReaderT f m (a -> b) -> ReaderT f m a -> ReaderT f m b #

(.>) :: ReaderT f m a -> ReaderT f m b -> ReaderT f m b #

(<.) :: ReaderT f m a -> ReaderT f m b -> ReaderT f m a #

liftF2 :: (a -> b -> c) -> ReaderT f m a -> ReaderT f m b -> ReaderT f m c #

(Representable f, Bind m) => Bind (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

(>>-) :: ReaderT f m a -> (a -> ReaderT f m b) -> ReaderT f m b #

join :: ReaderT f m (ReaderT f m a) -> ReaderT f m a #

(Representable f, Representable m, Semigroup (Rep f), Semigroup (Rep m)) => Extend (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

duplicated :: ReaderT f m a -> ReaderT f m (ReaderT f m a) #

extended :: (ReaderT f m a -> b) -> ReaderT f m a -> ReaderT f m b #

(Traversable1 f, Traversable1 m) => Traversable1 (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

Methods

traverse1 :: Apply f0 => (a -> f0 b) -> ReaderT f m a -> f0 (ReaderT f m b) #

sequence1 :: Apply f0 => ReaderT f m (f0 b) -> f0 (ReaderT f m b) #

type Rep (ReaderT f m) Source #

Instance details

Defined in Control.Monad.Representable.Reader

type Rep (ReaderT f m) = (Rep f, Rep m)

readerT :: Representable f => (Rep f -> m b) -> ReaderT f m b Source #

runReaderT :: Representable f => ReaderT f m b -> Rep f -> m b Source #

class Monad m => MonadReader r (m :: Type -> Type) | 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.

Minimal complete definition

(ask | reader), local

Methods

ask :: m r #

Retrieves the monad environment.

local #

Arguments

:: (r -> r)

The function to modify the environment.

-> m a

Reader to run in the modified environment.

-> m a