Control.Effect.Type.ReaderPrim

Effects

data ReaderPrim i m a where

A primitive effect that may be used for interpreters of connected Ask and Local effects.

This combines Ask and Local, which is relevant since certain monad transformers may only lift local if they also have access to ask.

ReaderPrim is only used as a primitive effect. If you define a Carrier that relies on a novel non-trivial monad transformer t, then you need to make a ThreadsEff t (ReaderPrim i) instance (if possible). threadReaderPrimViaClass and threadReaderPrimViaRegional can help you with that.

The following threading constraints accept ReaderPrim:

• ReaderThreads
• StateThreads
• StateLazyThreads
• ErrorThreads
• WriterThreads
• WriterLazyThreads
• NonDetThreads
• SteppedThreads
• ContThreads
• ContFastThreads

Constructors

ReaderPrimAsk :: ReaderPrim i m i

ReaderPrimLocal :: (i -> i) -> m a -> ReaderPrim i m a

Instances

ThreadsEff ListT (ReaderPrim i)

Defined in Control.Monad.Trans.List.Church

Methods

threadEff :: Monad m => (forall x. ReaderPrim i m x -> m x) -> ReaderPrim i (ListT m) a -> ListT m a

(Reifies s (ReifiedEffAlgebra (ReaderPrim i) m), Monad m) => MonadReader i (ViaAlg s (ReaderPrim i) m)

Defined in Control.Effect.Type.ReaderPrim

Methods

ask :: ViaAlg s (ReaderPrim i) m i

local :: (i -> i) -> ViaAlg s (ReaderPrim i) m a -> ViaAlg s (ReaderPrim i) m a

reader :: (i -> a) -> ViaAlg s (ReaderPrim i) m a

ThreadsEff (ExceptT e) (ReaderPrim threadedInput)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim threadedInput m x -> m x) -> ReaderPrim threadedInput (ExceptT e m) a -> ExceptT e m a

Monoid w => ThreadsEff (WriterT w) (ReaderPrim threadedInput)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim threadedInput m x -> m x) -> ReaderPrim threadedInput (WriterT w m) a -> WriterT w m a

ThreadsEff (StateT s) (ReaderPrim threadedInput)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim threadedInput m x -> m x) -> ReaderPrim threadedInput (StateT s m) a -> StateT s m a

ThreadsEff (ReaderT i') (ReaderPrim i)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim i m x -> m x) -> ReaderPrim i (ReaderT i' m) a -> ReaderT i' m a

ThreadsEff (StateT s) (ReaderPrim threadedInput)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim threadedInput m x -> m x) -> ReaderPrim threadedInput (StateT s m) a -> StateT s m a

Monoid w => ThreadsEff (WriterT w) (ReaderPrim threadedInput)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim threadedInput m x -> m x) -> ReaderPrim threadedInput (WriterT w m) a -> WriterT w m a

Monoid w => ThreadsEff (WriterT w) (ReaderPrim i)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim i m x -> m x) -> ReaderPrim i (WriterT w m) a -> WriterT w m a

ThreadsEff (FreeT f) (ReaderPrim i)

Defined in Control.Monad.Trans.Free.Church.Alternate

Methods

threadEff :: Monad m => (forall x. ReaderPrim i m x -> m x) -> ReaderPrim i (FreeT f m) a -> FreeT f m a

ThreadsEff (ContT r) (ReaderPrim threadedInput)

Defined in Control.Effect.Type.ReaderPrim

Methods

threadEff :: Monad m => (forall x. ReaderPrim threadedInput m x -> m x) -> ReaderPrim threadedInput (ContT r m) a -> ContT r m a

Threading utilities

threadReaderPrim :: forall i t m a. (MonadTrans t, Monad m) => ((forall x. ReaderPrim i m x -> m x) -> (i -> i) -> t m a -> t m a) -> (forall x. ReaderPrim i m x -> m x) -> ReaderPrim i (t m) a -> t m a

Construct a valid definition of threadEff for a ThreadsEff t (ReaderPrim w) instance only by specifying how ReaderPrimLocal should be lifted.

This uses lift to lift ReaderPrimAsk.

threadReaderPrimViaClass :: forall i t m a. Monad m => (RepresentationalT t, MonadTrans t, forall b. MonadReader i b => MonadReader i (t b)) => (forall x. ReaderPrim i m x -> m x) -> ReaderPrim i (t m) a -> t m a

A valid definition of threadEff for a ThreadsEff t (ReaderPrim i) instance, given that t lifts MonadReader i.

threadReaderPrimViaRegional :: forall i t m a. (Monad m, MonadTrans t, ThreadsEff t (Regional ())) => (forall x. ReaderPrim i m x -> m x) -> ReaderPrim i (t m) a -> t m a

A valid definition of threadEff for a ThreadsEff t (ReaderPrim i) instance, given that t threads Regional s for any s.