Safe Haskell	Safe-Inferred
Language	Haskell2010

Control.Monad.Ology.Specific.ReaderT

Contents

Orphan instances

Synopsis

mapReader :: (a -> b) -> Reader r a -> Reader r b
mapReaderT :: (m a -> n b) -> ReaderT r m a -> ReaderT r n b
runReader :: Reader r a -> r -> a
withReader :: (r' -> r) -> Reader r a -> Reader r' a
withReaderT :: forall r' r (m :: Type -> Type) a. (r' -> r) -> ReaderT r m a -> ReaderT r' m a
type Reader r = ReaderT r Identity
newtype ReaderT r (m :: Type -> Type) a = ReaderT {
- runReaderT :: r -> m a
}
reader :: forall (m :: Type -> Type) r a. Monad m => (r -> a) -> ReaderT r m a
local :: forall r (m :: Type -> Type) a. (r -> r) -> ReaderT r m a -> ReaderT r m a
asks :: forall (m :: Type -> Type) r a. Monad m => (r -> a) -> ReaderT r m a
ask :: forall (m :: Type -> Type) r. Monad m => ReaderT r m r
with :: r -> ReaderT r m a -> ReaderT r m a
readerTUnliftToT :: forall t m. (MonadTransUnlift t, MonadTunnelIO m) => ReaderT (WUnlift MonadTunnelIO t) m --> t m
tToReaderTUnlift :: MonadTunnelIO m => t m --> ReaderT (WUnlift Monad t) m

Documentation

mapReader :: (a -> b) -> Reader r a -> Reader r b #

Transform the value returned by a Reader.

runReader (mapReader f m) = f . runReader m

mapReaderT :: (m a -> n b) -> ReaderT r m a -> ReaderT r n b #

Transform the computation inside a ReaderT.

runReaderT (mapReaderT f m) = f . runReaderT m

runReader #

Arguments

:: Reader r a	A `Reader` to run.
-> r	An initial environment.
-> a

Runs a Reader and extracts the final value from it. (The inverse of reader.)

withReader #

Arguments

:: (r' -> r)	The function to modify the environment.
-> Reader r a	Computation to run in the modified environment.
-> Reader r' a

Execute a computation in a modified environment (a specialization of withReaderT).

runReader (withReader f m) = runReader m . f

withReaderT #

Arguments

:: forall r' r (m :: Type -> Type) a. (r' -> r)	The function to modify the environment.
-> ReaderT r m a	Computation to run in the modified environment.
-> ReaderT r' m a

Execute a computation in a modified environment (a more general version of local).

runReaderT (withReaderT f m) = runReaderT m . f

type Reader r = ReaderT r Identity #

The parameterizable reader monad.

Computations are functions of a shared environment.

The return function ignores the environment, while >>= passes the inherited environment to both subcomputations.

newtype ReaderT r (m :: Type -> Type) a #

The reader monad transformer, which adds a read-only environment to the given monad.

The return function ignores the environment, while >>= passes the inherited environment to both subcomputations.

Constructors

ReaderT
Fields runReaderT :: r -> m a

Instances

Instances details

TransConstraint MonadFail (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadFail m => Dict (MonadFail (ReaderT s m)) Source #
TransConstraint MonadFix (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadFix m => Dict (MonadFix (ReaderT s m)) Source #
TransConstraint MonadIO (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadIO m => Dict (MonadIO (ReaderT s m)) Source #
TransConstraint Applicative (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). Applicative m => Dict (Applicative (ReaderT s m)) Source #
TransConstraint Functor (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). Functor m => Dict (Functor (ReaderT s m)) Source #
TransConstraint Monad (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). Monad m => Dict (Monad (ReaderT s m)) Source #
TransConstraint MonadPlus (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadPlus m => Dict (MonadPlus (ReaderT s m)) Source #
TransConstraint MonadException (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadException m => Dict (MonadException (ReaderT r m)) Source #
TransConstraint MonadOuter (ReaderT s) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadOuter m => Dict (MonadOuter (ReaderT s m)) Source #
MonadCatch e m => MonadCatch e (ReaderT r m) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods catch :: ReaderT r m a -> (e -> ReaderT r m a) -> ReaderT r m a Source #
MonadThrow e m => MonadThrow e (ReaderT r m) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods throw :: e -> ReaderT r m a Source #
MonadTransAskUnlift (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods askUnlift :: forall (m :: Type -> Type). Monad m => ReaderT r m (WUnlift Monad (ReaderT r)) Source #
MonadTransCoerce (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods transCoerce :: forall (m1 :: Type -> Type) (m2 :: Type -> Type). Coercible m1 m2 => Dict (Coercible (ReaderT r m1) (ReaderT r m2)) Source #
MonadTransHoist (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hoist :: forall (m1 :: Type -> Type) (m2 :: Type -> Type). (Monad m1, Monad m2) => (m1 --> m2) -> ReaderT r m1 --> ReaderT r m2 Source #
MonadTransTunnel (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Associated Types type Tunnel (ReaderT r) :: Type -> Type Source # Methods tunnel :: Monad m => ((forall (m1 :: Type -> Type) a. Monad m1 => ReaderT r m1 a -> m1 (Tunnel (ReaderT r) a)) -> m (Tunnel (ReaderT r) r0)) -> ReaderT r m r0 Source #
MonadTransUnlift (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods liftWithUnlift :: MonadIO m => (Unlift MonadTunnelIO (ReaderT r) -> m r0) -> ReaderT r m r0 Source # getDiscardingUnlift :: forall (m :: Type -> Type). Monad m => ReaderT r m (WUnlift MonadTunnelIO (ReaderT r)) Source #
MonadTrans (ReaderT r)
Instance details Defined in Control.Monad.Trans.Reader Methods lift :: Monad m => m a -> ReaderT r m a #
TransConstraint (MonadCatch e) (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadCatch e m => Dict (MonadCatch e (ReaderT r m)) Source #
TransConstraint (MonadThrow e) (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods hasTransConstraint :: forall (m :: Type -> Type). MonadThrow e m => Dict (MonadThrow e (ReaderT r m)) Source #
MonadFail m => MonadFail (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods fail :: String -> ReaderT r m a #
MonadFix m => MonadFix (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods mfix :: (a -> ReaderT r m a) -> ReaderT r m a #
MonadIO m => MonadIO (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods liftIO :: IO a -> ReaderT r m a #
MonadZip m => MonadZip (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods mzip :: ReaderT r m a -> ReaderT r m b -> ReaderT r m (a, b) # mzipWith :: (a -> b -> c) -> ReaderT r m a -> ReaderT r m b -> ReaderT r m c # munzip :: ReaderT r m (a, b) -> (ReaderT r m a, ReaderT r m b) #
Contravariant m => Contravariant (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods contramap :: (a' -> a) -> ReaderT r m a -> ReaderT r m a' # (>$) :: b -> ReaderT r m b -> ReaderT r m a #
Alternative m => Alternative (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods empty :: ReaderT r m a # (<\|>) :: ReaderT r m a -> ReaderT r m a -> ReaderT r m a # some :: ReaderT r m a -> ReaderT r m [a] # many :: ReaderT r m a -> ReaderT r m [a] #
Applicative m => Applicative (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods pure :: a -> ReaderT r m a # (<>) :: ReaderT r m (a -> b) -> ReaderT r m a -> ReaderT r m b # liftA2 :: (a -> b -> c) -> ReaderT r m a -> ReaderT r m b -> ReaderT r m c # (>) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m b # (<*) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m a #
Functor m => Functor (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods fmap :: (a -> b) -> ReaderT r m a -> ReaderT r m b # (<$) :: a -> ReaderT r m b -> ReaderT r m a #
Monad m => Monad (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods (>>=) :: ReaderT r m a -> (a -> ReaderT r m b) -> ReaderT r m b # (>>) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m b # return :: a -> ReaderT r m a #
MonadPlus m => MonadPlus (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods mzero :: ReaderT r m a # mplus :: ReaderT r m a -> ReaderT r m a -> ReaderT r m a #
Invariant m => Invariant (ReaderT r m)	from the `transformers` package
Instance details Defined in Data.Functor.Invariant Methods invmap :: (a -> b) -> (b -> a) -> ReaderT r m a -> ReaderT r m b #
MonadException m => MonadException (ReaderT r m) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Associated Types type Exc (ReaderT r m) Source # Methods throwExc :: Exc (ReaderT r m) -> ReaderT r m a Source # catchExc :: ReaderT r m a -> (Exc (ReaderT r m) -> ReaderT r m a) -> ReaderT r m a Source #
MonadOuter m => MonadOuter (ReaderT r m) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT Methods getExtract :: ReaderT r m (WExtract (ReaderT r m)) Source #
type Tunnel (ReaderT r) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT type Tunnel (ReaderT r) = Identity
type Exc (ReaderT r m) Source #
Instance details Defined in Control.Monad.Ology.Specific.ReaderT type Exc (ReaderT r m) = Exc m

reader :: forall (m :: Type -> Type) r a. Monad m => (r -> a) -> ReaderT r m a #

Constructor for computations in the reader monad (equivalent to asks).

local #

Arguments

:: forall r (m :: Type -> Type) a. (r -> r)	The function to modify the environment.
-> ReaderT r m a	Computation to run in the modified environment.
-> ReaderT r m a

Execute a computation in a modified environment (a specialization of withReaderT).

runReaderT (local f m) = runReaderT m . f

asks #

Arguments

:: forall (m :: Type -> Type) r a. Monad m
=> (r -> a)	The selector function to apply to the environment.
-> ReaderT r m a

Retrieve a function of the current environment.

```
asks f = liftM f ask
```

ask :: forall (m :: Type -> Type) r. Monad m => ReaderT r m r #

Fetch the value of the environment.

with :: r -> ReaderT r m a -> ReaderT r m a Source #

readerTUnliftToT :: forall t m. (MonadTransUnlift t, MonadTunnelIO m) => ReaderT (WUnlift MonadTunnelIO t) m --> t m Source #

tToReaderTUnlift :: MonadTunnelIO m => t m --> ReaderT (WUnlift Monad t) m Source #

Orphan instances

TransConstraint MonadFail (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadFail m => Dict (MonadFail (ReaderT s m)) Source #
TransConstraint MonadFix (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadFix m => Dict (MonadFix (ReaderT s m)) Source #
TransConstraint MonadIO (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadIO m => Dict (MonadIO (ReaderT s m)) Source #
TransConstraint Applicative (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). Applicative m => Dict (Applicative (ReaderT s m)) Source #
TransConstraint Functor (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). Functor m => Dict (Functor (ReaderT s m)) Source #
TransConstraint Monad (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). Monad m => Dict (Monad (ReaderT s m)) Source #
TransConstraint MonadPlus (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadPlus m => Dict (MonadPlus (ReaderT s m)) Source #
TransConstraint MonadException (ReaderT r) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadException m => Dict (MonadException (ReaderT r m)) Source #
TransConstraint MonadOuter (ReaderT s) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadOuter m => Dict (MonadOuter (ReaderT s m)) Source #
MonadCatch e m => MonadCatch e (ReaderT r m) Source #
Instance details Methods catch :: ReaderT r m a -> (e -> ReaderT r m a) -> ReaderT r m a Source #
MonadThrow e m => MonadThrow e (ReaderT r m) Source #
Instance details Methods throw :: e -> ReaderT r m a Source #
MonadTransAskUnlift (ReaderT r) Source #
Instance details Methods askUnlift :: forall (m :: Type -> Type). Monad m => ReaderT r m (WUnlift Monad (ReaderT r)) Source #
MonadTransCoerce (ReaderT r) Source #
Instance details Methods transCoerce :: forall (m1 :: Type -> Type) (m2 :: Type -> Type). Coercible m1 m2 => Dict (Coercible (ReaderT r m1) (ReaderT r m2)) Source #
MonadTransHoist (ReaderT r) Source #
Instance details Methods hoist :: forall (m1 :: Type -> Type) (m2 :: Type -> Type). (Monad m1, Monad m2) => (m1 --> m2) -> ReaderT r m1 --> ReaderT r m2 Source #
MonadTransTunnel (ReaderT r) Source #
Instance details Associated Types type Tunnel (ReaderT r) :: Type -> Type Source # Methods tunnel :: Monad m => ((forall (m1 :: Type -> Type) a. Monad m1 => ReaderT r m1 a -> m1 (Tunnel (ReaderT r) a)) -> m (Tunnel (ReaderT r) r0)) -> ReaderT r m r0 Source #
MonadTransUnlift (ReaderT r) Source #
Instance details Methods liftWithUnlift :: MonadIO m => (Unlift MonadTunnelIO (ReaderT r) -> m r0) -> ReaderT r m r0 Source # getDiscardingUnlift :: forall (m :: Type -> Type). Monad m => ReaderT r m (WUnlift MonadTunnelIO (ReaderT r)) Source #
TransConstraint (MonadCatch e) (ReaderT r) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadCatch e m => Dict (MonadCatch e (ReaderT r m)) Source #
TransConstraint (MonadThrow e) (ReaderT r) Source #
Instance details Methods hasTransConstraint :: forall (m :: Type -> Type). MonadThrow e m => Dict (MonadThrow e (ReaderT r m)) Source #
MonadException m => MonadException (ReaderT r m) Source #
Instance details Associated Types type Exc (ReaderT r m) Source # Methods throwExc :: Exc (ReaderT r m) -> ReaderT r m a Source # catchExc :: ReaderT r m a -> (Exc (ReaderT r m) -> ReaderT r m a) -> ReaderT r m a Source #
MonadOuter m => MonadOuter (ReaderT r m) Source #
Instance details Methods getExtract :: ReaderT r m (WExtract (ReaderT r m)) Source #