multistate-0.8.0.2: like mtl's ReaderT / WriterT / StateT, but more than one contained value/type.

Safe HaskellSafe
LanguageHaskell2010

Control.Monad.Trans.MultiReader

Contents

Description

The multi-valued version of mtl's Reader / ReaderT / MonadReader

Synopsis

MultiReaderT

newtype MultiReaderT x m a Source #

A Reader transformer monad patameterized by:

  • x - The list of types constituting the environment / input (to be read),
  • m - The inner monad.

MultiReaderT corresponds to mtl's ReaderT, but can contain a heterogenous list of types.

This heterogenous list is represented using Types.Data.List, i.e:

  • '[] - The empty list,
  • a ': b - A list where a is an arbitrary type and b is the rest list.

For example,

MultiReaderT '[Int, Bool] :: (* -> *) -> (* -> *)

is a Reader transformer containing the types [Int, Bool].

Constructors

MultiReaderT 

Fields

Instances

MonadBase b m => MonadBase b (MultiReaderT r m) Source # 

Methods

liftBase :: b α -> MultiReaderT r m α #

MonadBaseControl b m => MonadBaseControl b (MultiReaderT r m) Source # 

Associated Types

type StM (MultiReaderT r m :: * -> *) a :: * #

Methods

liftBaseWith :: (RunInBase (MultiReaderT r m) b -> b a) -> MultiReaderT r m a #

restoreM :: StM (MultiReaderT r m) a -> MultiReaderT r m a #

MonadState s m => MonadState s (MultiReaderT c m) Source # 

Methods

get :: MultiReaderT c m s #

put :: s -> MultiReaderT c m () #

state :: (s -> (a, s)) -> MultiReaderT c m a #

MonadWriter w m => MonadWriter w (MultiReaderT c m) Source # 

Methods

writer :: (a, w) -> MultiReaderT c m a #

tell :: w -> MultiReaderT c m () #

listen :: MultiReaderT c m a -> MultiReaderT c m (a, w) #

pass :: MultiReaderT c m (a, w -> w) -> MultiReaderT c m a #

(Monad m, ContainsType a c) => MonadMultiReader a (MultiReaderT c m) Source # 

Methods

mAsk :: MultiReaderT c m a Source #

(Monad m, ContainsType a c) => MonadMultiGet a (MultiReaderT c m) Source # 

Methods

mGet :: MultiReaderT c m a Source #

MonadTrans (MultiReaderT x) Source # 

Methods

lift :: Monad m => m a -> MultiReaderT x m a #

MonadTransControl (MultiReaderT r) Source # 

Associated Types

type StT (MultiReaderT r :: (* -> *) -> * -> *) a :: * #

Methods

liftWith :: Monad m => (Run (MultiReaderT r) -> m a) -> MultiReaderT r m a #

restoreT :: Monad m => m (StT (MultiReaderT r) a) -> MultiReaderT r m a #

Monad m => Monad (MultiReaderT x m) Source # 

Methods

(>>=) :: MultiReaderT x m a -> (a -> MultiReaderT x m b) -> MultiReaderT x m b #

(>>) :: MultiReaderT x m a -> MultiReaderT x m b -> MultiReaderT x m b #

return :: a -> MultiReaderT x m a #

fail :: String -> MultiReaderT x m a #

Functor f => Functor (MultiReaderT x f) Source # 

Methods

fmap :: (a -> b) -> MultiReaderT x f a -> MultiReaderT x f b #

(<$) :: a -> MultiReaderT x f b -> MultiReaderT x f a #

MonadFix m => MonadFix (MultiReaderT r m) Source # 

Methods

mfix :: (a -> MultiReaderT r m a) -> MultiReaderT r m a #

(Applicative m, Monad m) => Applicative (MultiReaderT x m) Source # 

Methods

pure :: a -> MultiReaderT x m a #

(<*>) :: MultiReaderT x m (a -> b) -> MultiReaderT x m a -> MultiReaderT x m b #

(*>) :: MultiReaderT x m a -> MultiReaderT x m b -> MultiReaderT x m b #

(<*) :: MultiReaderT x m a -> MultiReaderT x m b -> MultiReaderT x m a #

MonadIO m => MonadIO (MultiReaderT c m) Source # 

Methods

liftIO :: IO a -> MultiReaderT c m a #

(Functor m, Applicative m, MonadPlus m) => Alternative (MultiReaderT c m) Source # 

Methods

empty :: MultiReaderT c m a #

(<|>) :: MultiReaderT c m a -> MultiReaderT c m a -> MultiReaderT c m a #

some :: MultiReaderT c m a -> MultiReaderT c m [a] #

many :: MultiReaderT c m a -> MultiReaderT c m [a] #

MonadPlus m => MonadPlus (MultiReaderT c m) Source # 

Methods

mzero :: MultiReaderT c m a #

mplus :: MultiReaderT c m a -> MultiReaderT c m a -> MultiReaderT c m a #

type StT (MultiReaderT r) a Source # 
type StT (MultiReaderT r) a = (a, HList r)
type StM (MultiReaderT r m) a Source # 
type StM (MultiReaderT r m) a = ComposeSt (MultiReaderT r) m a

type MultiReaderTNull = MultiReaderT '[] Source #

A MultiReader transformer carrying an empty state.

type MultiReader x = MultiReaderT x Identity Source #

A reader monad parameterized by the list of types x of the environment / input to carry.

Similar to Reader r = ReaderT r Identity

MonadMultiReader class

class Monad m => MonadMultiReader a m where Source #

All methods must be defined.

The idea is: Any monad stack is instance of MonadMultiReader a, iff the stack contains a MultiReaderT x with a element of x.

Minimal complete definition

mAsk

Methods

mAsk :: m a Source #

Instances

(MonadTrans t, Monad (t m), MonadMultiReader a m) => MonadMultiReader a (t m) Source # 

Methods

mAsk :: t m a Source #

(Monad m, ContainsType a c) => MonadMultiReader a (MultiReaderT c m) Source # 

Methods

mAsk :: MultiReaderT c m a Source #

(Monad m, ContainsType a c) => MonadMultiReader a (MultiReaderT c m) Source # 

Methods

mAsk :: MultiReaderT c m a Source #

(Monad m, ContainsType a r) => MonadMultiReader a (MultiRWST r w s m) Source # 

Methods

mAsk :: MultiRWST r w s m a Source #

(Monad m, ContainsType a r) => MonadMultiReader a (MultiRWST r w s m) Source # 

Methods

mAsk :: MultiRWST r w s m a Source #

run-functions

runMultiReaderT :: Monad m => HList r -> MultiReaderT r m a -> m a Source #

runMultiReaderT_ :: Functor m => HList r -> MultiReaderT r m a -> m () Source #

with-functions (single reader)

withMultiReader :: Monad m => r -> MultiReaderT (r ': rs) m a -> MultiReaderT rs m a Source #

withMultiReader_ :: (Functor m, Monad m) => r -> MultiReaderT (r ': rs) m a -> MultiReaderT rs m () Source #

with-functions (multiple readers)

withMultiReaders :: Monad m => HList r1 -> MultiReaderT (Append r1 r2) m a -> MultiReaderT r2 m a Source #

withMultiReaders_ :: (Functor m, Monad m) => HList r1 -> MultiReaderT (Append r1 r2) m a -> MultiReaderT r2 m () Source #

without-function (single reader)

withoutMultiReader :: Monad m => MultiReaderT rs m a -> MultiReaderT (r ': rs) m a Source #

inflate-function (run ReaderT in MultiReaderT)

inflateReader :: (Monad m, ContainsType r rs) => ReaderT r m a -> MultiReaderT rs m a Source #

other functions

mapMultiReaderT :: (m (a, HList w) -> m' (a', HList w)) -> MultiReaderT w m a -> MultiReaderT w m' a' Source #

Map both the return value and the environment of a computation using the given function.

Note that there is a difference to mtl's ReaderT, where it is not possible to modify the environment.

mGetRaw :: Monad m => MultiReaderT a m (HList a) Source #

A raw extractor of the contained HList (i.e. the complete Reader).

mPutRaw :: Monad m => HList s -> MultiReaderT s m () Source #