Control.Ether.Wrapped

Annotating monads with tags to turn untagged constraints into tagged ones.

import qualified Control.Monad.State as T
import Control.Ether.TH (ethereal)
import Control.Monad.Ether.State (MonadState)
import Control.Ether.Wrapped (ethered)

ethereal "Foo" "foo"

f :: T.MonadState Int m => m String
f = fmap show T.get

g :: MonadState Foo Int m => m String
g = ethered foo f

Documentation

newtype WrappedEther tag m a

Wrap a monad to attach a tag to it.

Constructors

WrapEther

Fields

unwrapEther :: m a

Instances

MonadReader tag r m => MonadReader tag r (WrappedEther tag' m)

MonadState tag s m => MonadState tag s (WrappedEther tag' m)

MonadExcept tag e m => MonadExcept tag e (WrappedEther tag' m)

MonadWriter tag w m => MonadWriter tag w (WrappedEther tag' m)

MonadExcept tag e m => MonadError e (WrappedEther tag m)

MonadReader tag r m => MonadReader r (WrappedEther tag m)

MonadState tag s m => MonadState s (WrappedEther tag m)

MonadWriter tag w m => MonadWriter w (WrappedEther tag m)

Monad m => Monad (WrappedEther tag m)

Functor m => Functor (WrappedEther tag m)

MonadFix m => MonadFix (WrappedEther tag m)

Applicative m => Applicative (WrappedEther tag m)

Alternative m => Alternative (WrappedEther tag m)

MonadPlus m => MonadPlus (WrappedEther tag m)

MonadIO m => MonadIO (WrappedEther tag m)

ethered :: proxy tag -> WrappedEther tag m a -> m a

Annotate a polymorphic monadic computation with a tag.