Servant.Utils.Enter

Documentation

class Enter typ arg ret | typ arg -> ret, typ ret -> arg where

Methods

enter :: arg -> typ -> ret

Instances

Enter (m a) ((:~>) m n) (n a)

Enter b arg ret => Enter (a -> b) arg (a -> ret)

(Enter typ1 arg1 ret1, Enter typ2 arg2 ret2, (~) * arg1 arg2) => Enter ((:<|>) typ1 typ2) arg1 ((:<|>) ret1 ret2)

Servant combinators

Useful instances

newtype m :~> n

A natural transformation from m to n. Used to enter particular datatypes.

Constructors

Nat

Fields

unNat :: forall a. m a -> n a

Instances

Enter (m a) ((:~>) m n) (n a)

Category (* -> *) (:~>)

liftNat :: (MonadTrans t, Monad m) => m :~> t m

Like lift.

runReaderTNat :: r -> ReaderT r m :~> m

evalStateTLNat :: Monad m => s -> StateT s m :~> m

evalStateTSNat :: Monad m => s -> StateT s m :~> m

logWriterTSNat :: MonadIO m => (w -> IO ()) -> WriterT w m :~> m

Log the contents of WriterT with the function provided as the first argument, and return the value of the WriterT computation

logWriterTLNat :: MonadIO m => (w -> IO ()) -> WriterT w m :~> m

Like logWriterTSNat, but for strict WriterT.

hoistNat :: (MFunctor t, Monad m) => (m :~> n) -> t m :~> t n

Like mmorph's hoist.

embedNat :: (MMonad t, Monad n) => (m :~> t n) -> t m :~> t n

Like mmorph's embed.

squashNat :: (Monad m, MMonad t) => t (t m) :~> t m

Like mmorph's squash.

generalizeNat :: Applicative m => Identity :~> m

Like mmorph's generalize.