{-# LANGUAGE RankNTypes #-}
module Control.Foldl.Optics where

import Data.Profunctor

type Prism s t a b = forall p f. (Choice p, Applicative f) => p a (f b) -> p s (f t)

type Prism' s a = Prism s s a a

prism :: (b -> t) -> (s -> Either t a) -> Prism s t a b
prism :: forall b t s a. (b -> t) -> (s -> Either t a) -> Prism s t a b
prism b -> t
bt s -> Either t a
seta = forall (p :: * -> * -> *) a b c d.
Profunctor p =>
(a -> b) -> (c -> d) -> p b c -> p a d
dimap s -> Either t a
seta (forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either forall (f :: * -> *) a. Applicative f => a -> f a
pure (forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap b -> t
bt)) forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (p :: * -> * -> *) a b c.
Choice p =>
p a b -> p (Either c a) (Either c b)
right'
{-# INLINE prism #-}

_Left :: Prism (Either a c) (Either b c) a b
_Left :: forall a c b. Prism (Either a c) (Either b c) a b
_Left = forall b t s a. (b -> t) -> (s -> Either t a) -> Prism s t a b
prism forall a b. a -> Either a b
Left forall a b. (a -> b) -> a -> b
$ forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either forall a b. b -> Either a b
Right (forall a b. a -> Either a b
Left forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. b -> Either a b
Right)
{-# INLINE _Left #-}

_Right :: Prism (Either c a) (Either c b) a b
_Right :: forall c a b. Prism (Either c a) (Either c b) a b
_Right = forall b t s a. (b -> t) -> (s -> Either t a) -> Prism s t a b
prism forall a b. b -> Either a b
Right forall a b. (a -> b) -> a -> b
$ forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall a b. a -> Either a b
Left forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) forall a b. b -> Either a b
Right
{-# INLINE _Right #-}