Control.Carrier.Interpret

Provides an InterpretC carrier capable of interpreting an arbitrary effect using a passed-in higher order function to interpret that effect. This is suitable for prototyping new effects quickly.

Interpret carrier

runInterpret :: (HFunctor eff, Monad m) => (forall x. eff m x -> m x) -> (forall s. Reifies s (Handler eff m) => InterpretC s eff m a) -> m a

Interpret an effect using a higher-order function.

Note that due to the higher-rank type, you have to use either $ or explicit application when applying this interpreter. That is, you will need to write runInterpret f (runInterpret g myPrgram) or runInterpret f $ runInterpret g $ myProgram. If you try and write runInterpret f . runInterpret g, you will unfortunately get a rather scary type error!

Since: 1.0.0.0

runInterpretState :: (HFunctor eff, Monad m) => (forall x. s -> eff (StateC s m) x -> m (s, x)) -> s -> (forall t. Reifies t (Handler eff (StateC s m)) => InterpretC t eff (StateC s m) a) -> m (s, a)

Interpret an effect using a higher-order function with some state variable.

Since: 1.0.0.0

newtype InterpretC s (sig :: (* -> *) -> * -> *) m a

Since: 1.0.0.0

Constructors

InterpretC (m a)

Instances

MonadTrans (InterpretC s sig)

Defined in Control.Carrier.Interpret

Methods

lift :: Monad m => m a -> InterpretC s sig m a

(HFunctor eff, HFunctor sig, Reifies s (Handler eff m), Monad m, Algebra sig m) => Algebra (eff :+: sig) (InterpretC s eff m)

Defined in Control.Carrier.Interpret

Methods

alg :: (eff :+: sig) (InterpretC s eff m) a -> InterpretC s eff m a

Monad m => Monad (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

(>>=) :: InterpretC s sig m a -> (a -> InterpretC s sig m b) -> InterpretC s sig m b

(>>) :: InterpretC s sig m a -> InterpretC s sig m b -> InterpretC s sig m b

return :: a -> InterpretC s sig m a

Functor m => Functor (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

fmap :: (a -> b) -> InterpretC s sig m a -> InterpretC s sig m b

(<$) :: a -> InterpretC s sig m b -> InterpretC s sig m a

MonadFix m => MonadFix (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

mfix :: (a -> InterpretC s sig m a) -> InterpretC s sig m a

MonadFail m => MonadFail (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

fail :: String -> InterpretC s sig m a

Applicative m => Applicative (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

pure :: a -> InterpretC s sig m a

(<*>) :: InterpretC s sig m (a -> b) -> InterpretC s sig m a -> InterpretC s sig m b

liftA2 :: (a -> b -> c) -> InterpretC s sig m a -> InterpretC s sig m b -> InterpretC s sig m c

(*>) :: InterpretC s sig m a -> InterpretC s sig m b -> InterpretC s sig m b

(<*) :: InterpretC s sig m a -> InterpretC s sig m b -> InterpretC s sig m a

MonadIO m => MonadIO (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

liftIO :: IO a -> InterpretC s sig m a

Alternative m => Alternative (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

empty :: InterpretC s sig m a

(<|>) :: InterpretC s sig m a -> InterpretC s sig m a -> InterpretC s sig m a

some :: InterpretC s sig m a -> InterpretC s sig m [a]

many :: InterpretC s sig m a -> InterpretC s sig m [a]

MonadPlus m => MonadPlus (InterpretC s sig m)

Defined in Control.Carrier.Interpret

Methods

mzero :: InterpretC s sig m a

mplus :: InterpretC s sig m a -> InterpretC s sig m a -> InterpretC s sig m a

class Reifies s a | s -> a

Minimal complete definition

reflect

data Handler sig m

A Handler is a function that interprets effects described by sig into the carrier monad m.

Re-exports

class (HFunctor sig, Monad m) => Algebra sig m | m -> sig

The class of carriers (results) for algebras (effect handlers) over signatures (effects), whose actions are given by the alg method.

Since: 1.0.0.0

Minimal complete definition

alg

Instances

Algebra Choose NonEmpty

Defined in Control.Algebra

Methods

alg :: Choose NonEmpty a -> NonEmpty a

Algebra Empty Maybe

Defined in Control.Algebra

Methods

alg :: Empty Maybe a -> Maybe a

Algebra NonDet []

Defined in Control.Algebra

Methods

alg :: NonDet [] a -> [a]

Algebra sig m => Algebra sig (Alt m)

This instance permits effectful actions to be lifted into the Alt monad, which eases the invocation of repeated alternation with <|>:

a <|> b <|> c <|> d

is equivalent to

getAlt (mconcat [a, b, c, d])

Since: 1.0.1.0

Defined in Control.Algebra

Methods

alg :: sig (Alt m) a -> Alt m a

Algebra sig m => Algebra sig (Ap m)

This instance permits effectful actions to be lifted into the Ap monad given a monoidal return type, which can provide clarity when chaining calls to mappend.

mappend <$> act1 <*> (mappend <$> act2 <*> act3)

is equivalent to

getAp (act1 <> act2 <> act3)

Since: 1.0.1.0

Defined in Control.Algebra

Methods

alg :: sig (Ap m) a -> Ap m a

Algebra sig m => Algebra sig (IdentityT m)

Defined in Control.Algebra

Methods

alg :: sig (IdentityT m) a -> IdentityT m a

Algebra (Lift IO) IO

Defined in Control.Algebra

Methods

alg :: Lift IO IO a -> IO a

Algebra (Lift Identity) Identity

Defined in Control.Algebra

Methods

alg :: Lift Identity Identity a -> Identity a

Monad m => Algebra (Lift m) (LiftC m)

Defined in Control.Carrier.Lift

Methods

alg :: Lift m (LiftC m) a -> LiftC m a

Algebra (Error e) (Either e)

Defined in Control.Algebra

Methods

alg :: Error e (Either e) a -> Either e a

Monoid w => Algebra (Writer w) ((,) w)

Defined in Control.Algebra

Methods

alg :: Writer w ((,) w) a -> (w, a)

Algebra (Reader r) ((->) r :: Type -> Type)

Defined in Control.Algebra

Methods

alg :: Reader r ((->) r) a -> r -> a

(Algebra sig m, Effect sig) => Algebra (Choose :+: sig) (ChooseC m)

Defined in Control.Carrier.Choose.Church

Methods

alg :: (Choose :+: sig) (ChooseC m) a -> ChooseC m a

(Algebra sig m, Effect sig) => Algebra (Empty :+: sig) (EmptyC m)

Defined in Control.Carrier.Empty.Maybe

Methods

alg :: (Empty :+: sig) (EmptyC m) a -> EmptyC m a

(Algebra sig m, Effect sig) => Algebra (NonDet :+: sig) (NonDetC m)

Defined in Control.Carrier.NonDet.Church

Methods

alg :: (NonDet :+: sig) (NonDetC m) a -> NonDetC m a

(MonadIO m, Algebra sig m) => Algebra (Trace :+: sig) (TraceC m)

Defined in Control.Carrier.Trace.Printing

Methods

alg :: (Trace :+: sig) (TraceC m) a -> TraceC m a

Algebra sig m => Algebra (Trace :+: sig) (TraceC m)

Defined in Control.Carrier.Trace.Ignoring

Methods

alg :: (Trace :+: sig) (TraceC m) a -> TraceC m a

(Algebra sig m, Effect sig) => Algebra (Trace :+: sig) (TraceC m)

Defined in Control.Carrier.Trace.Returning

Methods

alg :: (Trace :+: sig) (TraceC m) a -> TraceC m a

(Algebra sig m, Effect sig) => Algebra (Fail :+: sig) (FailC m)

Defined in Control.Carrier.Fail.Either

Methods

alg :: (Fail :+: sig) (FailC m) a -> FailC m a

(Algebra sig m, Effect sig) => Algebra (Fresh :+: sig) (FreshC m)

Defined in Control.Carrier.Fresh.Strict

Methods

alg :: (Fresh :+: sig) (FreshC m) a -> FreshC m a

(Algebra sig m, Effect sig) => Algebra (Cut :+: (NonDet :+: sig)) (CutC m)

Defined in Control.Carrier.Cut.Church

Methods

alg :: (Cut :+: (NonDet :+: sig)) (CutC m) a -> CutC m a

(Algebra sig m, Effect sig) => Algebra (Cull :+: (NonDet :+: sig)) (CullC m)

Defined in Control.Carrier.Cull.Church

Methods

alg :: (Cull :+: (NonDet :+: sig)) (CullC m) a -> CullC m a

Algebra sig m => Algebra (Reader r :+: sig) (ReaderT r m)

Defined in Control.Algebra

Methods

alg :: (Reader r :+: sig) (ReaderT r m) a -> ReaderT r m a

Algebra sig m => Algebra (Reader r :+: sig) (ReaderC r m)

Defined in Control.Carrier.Reader

Methods

alg :: (Reader r :+: sig) (ReaderC r m) a -> ReaderC r m a

(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateT s m)

Defined in Control.Algebra

Methods

alg :: (State s :+: sig) (StateT s m) a -> StateT s m a

(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateT s m)

Defined in Control.Algebra

Methods

alg :: (State s :+: sig) (StateT s m) a -> StateT s m a

(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateC s m)

Defined in Control.Carrier.State.Strict

Methods

alg :: (State s :+: sig) (StateC s m) a -> StateC s m a

(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateC s m)

Defined in Control.Carrier.State.Lazy

Methods

alg :: (State s :+: sig) (StateC s m) a -> StateC s m a

(Algebra sig m, Effect sig) => Algebra (Throw e :+: sig) (ThrowC e m)

Defined in Control.Carrier.Throw.Either

Methods

alg :: (Throw e :+: sig) (ThrowC e m) a -> ThrowC e m a

(Algebra sig m, Effect sig) => Algebra (Error e :+: sig) (ExceptT e m)

Defined in Control.Algebra

Methods

alg :: (Error e :+: sig) (ExceptT e m) a -> ExceptT e m a

(Algebra sig m, Effect sig) => Algebra (Error e :+: sig) (ErrorC e m)

Defined in Control.Carrier.Error.Either

Methods

alg :: (Error e :+: sig) (ErrorC e m) a -> ErrorC e m a

(Algebra sig m, Effect sig, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m)

Defined in Control.Algebra

Methods

alg :: (Writer w :+: sig) (WriterT w m) a -> WriterT w m a

(Algebra sig m, Effect sig, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m)

Defined in Control.Algebra

Methods

alg :: (Writer w :+: sig) (WriterT w m) a -> WriterT w m a

(Monoid w, Algebra sig m, Effect sig) => Algebra (Writer w :+: sig) (WriterC w m)

Defined in Control.Carrier.Writer.Strict

Methods

alg :: (Writer w :+: sig) (WriterC w m) a -> WriterC w m a

(HFunctor eff, HFunctor sig, Reifies s (Handler eff m), Monad m, Algebra sig m) => Algebra (eff :+: sig) (InterpretC s eff m)

Defined in Control.Carrier.Interpret

Methods

alg :: (eff :+: sig) (InterpretC s eff m) a -> InterpretC s eff m a

(Algebra sig m, Effect sig, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m)

Defined in Control.Algebra

Methods

alg :: (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) a -> RWST r w s m a

(Algebra sig m, Effect sig, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m)

Defined in Control.Algebra

Methods

alg :: (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) a -> RWST r w s m a

type Has eff sig m = (Members eff sig, Algebra sig m)

m is a carrier for sig containing eff.

Note that if eff is a sum, it will be decomposed into multiple Member constraints. While this technically allows one to combine multiple unrelated effects into a single Has constraint, doing so has two significant drawbacks:

1. Due to a problem with recursive type families, this can lead to significantly slower compiles.
2. It defeats ghc’s warnings for redundant constraints, and thus can lead to a proliferation of redundant constraints as code is changed.

run :: Identity a -> a

Run an action exhausted of effects to produce its final result value.

Since: 1.0.0.0