Control.Monad.Trans.Wedge

This module contains utilities for the monad transformer for the pointed coproduct.

Monad transformer

data WedgeT a m b

A monad transformer for the pointed product, parameterized by:

• a - the value on the left
• b - the value on the right
• m - The monad over a pointed coproduct (see: Wedge).

This monad transformer is similar to ExceptT, except with the possibility of an empty unital value.

Instances

(Semigroup t, MonadRWS r w s m) => MonadRWS r w s (WedgeT t m)

Defined in Control.Monad.Trans.Wedge

(MonadWriter w m, Semigroup t) => MonadWriter w (WedgeT t m)

Defined in Control.Monad.Trans.Wedge

Methods

writer :: (a, w) -> WedgeT t m a

tell :: w -> WedgeT t m ()

listen :: WedgeT t m a -> WedgeT t m (a, w)

pass :: WedgeT t m (a, w -> w) -> WedgeT t m a

(MonadState s m, Semigroup t) => MonadState s (WedgeT t m)

Defined in Control.Monad.Trans.Wedge

Methods

get :: WedgeT t m s

put :: s -> WedgeT t m ()

state :: (s -> (a, s)) -> WedgeT t m a

(MonadReader r m, Semigroup t) => MonadReader r (WedgeT t m)

Defined in Control.Monad.Trans.Wedge

Methods

ask :: WedgeT t m r

local :: (r -> r) -> WedgeT t m a -> WedgeT t m a

reader :: (r -> a) -> WedgeT t m a

(MonadError e m, Semigroup e) => MonadError e (WedgeT e m)

Defined in Control.Monad.Trans.Wedge

Methods

throwError :: e -> WedgeT e m a

catchError :: WedgeT e m a -> (e -> WedgeT e m a) -> WedgeT e m a

MonadTrans (WedgeT a)

Defined in Control.Monad.Trans.Wedge

Methods

lift :: Monad m => m a0 -> WedgeT a m a0

(Semigroup a, Monad m) => Monad (WedgeT a m)

Defined in Control.Monad.Trans.Wedge

Methods

(>>=) :: WedgeT a m a0 -> (a0 -> WedgeT a m b) -> WedgeT a m b

(>>) :: WedgeT a m a0 -> WedgeT a m b -> WedgeT a m b

return :: a0 -> WedgeT a m a0

Functor f => Functor (WedgeT a f)

Defined in Control.Monad.Trans.Wedge

Methods

fmap :: (a0 -> b) -> WedgeT a f a0 -> WedgeT a f b

(<$) :: a0 -> WedgeT a f b -> WedgeT a f a0

(Semigroup a, Applicative f) => Applicative (WedgeT a f)

Defined in Control.Monad.Trans.Wedge

Methods

pure :: a0 -> WedgeT a f a0

(<*>) :: WedgeT a f (a0 -> b) -> WedgeT a f a0 -> WedgeT a f b

liftA2 :: (a0 -> b -> c) -> WedgeT a f a0 -> WedgeT a f b -> WedgeT a f c

(*>) :: WedgeT a f a0 -> WedgeT a f b -> WedgeT a f b

(<*) :: WedgeT a f a0 -> WedgeT a f b -> WedgeT a f a0

Combinators

mapWedgeT :: (m (Wedge a b) -> n (Wedge c d)) -> WedgeT a m b -> WedgeT c n d

Map both the left and right values and output of a computation using the given function.

• runWedgeT (mapWedgeT f m) = f . runWedgeT m