49e56e3 · semi-iso-optics

git.iko.soy/semi-iso-optics

Add instances for Dual categories.

commit49e56e33c8cdc9412f0012422e299fce8e12a887 authorPaweł Nowak <pawel834@gmail.com> dateFri 12 Dec 2014, 19:30 (12 years ago) parent8a6f530

3 files changed+19−1

compare with master

unifiedsplit

Control/Category/Structures.hs+12 Control/SIArrow.hs+6 semi-iso.cabal+1−1

Control/Category/Structures.hs+12

@@ -1,4 +1,5 @@

11{-# LANGUAGE TypeFamilies #-}

2+{-# LANGUAGE FlexibleInstances #-}

23{-# LANGUAGE ConstraintKinds #-}

34{- |

45Module : Control.Category.Structures

@@ -20,6 +21,7 @@ import Control.Arrow (Kleisli(..))

2021import qualified Control.Arrow as BadArrow

2122import Control.Category

2223import Control.Monad

24+import Data.Semigroupoid.Dual

2325import Prelude hiding (id, (.))

2426

2527infixl 3 ***

@@ -50,6 +52,9 @@ class Category cat => Products cat where

5052instance Monad m => Products (Kleisli m) where

5153 (***) = (BadArrow.***)

5254

55+instance Products cat => Products (Dual cat) where

56+ Dual f *** Dual g = Dual $ f *** g

57+

5358instance Products (->) where

5459 (***) = (BadArrow.***)

5560

@@ -77,6 +82,9 @@ class Category cat => Coproducts cat where

7782instance Monad m => Coproducts (Kleisli m) where

7883 (+++) = (BadArrow.+++)

7984

85+instance Coproducts cat => Coproducts (Dual cat) where

86+ Dual f +++ Dual g = Dual $ f +++ g

87+

8088instance Coproducts (->) where

8189 (+++) = (BadArrow.+++)

8290

@@ -93,6 +101,10 @@ instance MonadPlus m => CatPlus (Kleisli m) where

93101 cempty = BadArrow.zeroArrow

94102 (/+/) = (BadArrow.<+>)

95103

104+instance CatPlus cat => CatPlus (Dual cat) where

105+ cempty = Dual cempty

106+ Dual f /+/ Dual g = Dual $ f /+/ g

107+

96108-- | A category transformer.

97109class CatTrans t where

98110 -- | Lift an arrow from the base category.

Control/SIArrow.hs+6

@@ -39,8 +39,10 @@ import Control.Category

3939import Control.Category.Structures

4040import Control.Lens.Cons

4141import Control.Lens.Empty

42+import Control.Lens.Iso

4243import Control.Lens.SemiIso

4344import Control.Monad

45+import Data.Semigroupoid.Dual

4446import Data.Tuple.Morph

4547import Prelude hiding (id, (.))

4648

@@ -94,6 +96,10 @@ instance MonadPlus m => SIArrow (Kleisli m) where

9496 siarr ai = Kleisli $ either fail return . apply ai

9597 sibind ai = Kleisli $ \a -> either fail (($ a) . runKleisli) $ apply ai a

9698

99+instance SIArrow cat => SIArrow (Dual cat) where

100+ siarr = Dual . sipure

101+ sibind ai = Dual $ sibind (iso id getDual . rev ai . iso getDual id)

102+

97103instance SIArrow ReifiedSemiIso' where

98104 siarr = reifySemiIso

99105 sibind ai = ReifiedSemiIso' $

semi-iso.cabal+1−1

@@ -66,6 +66,6 @@ library

6666 Control.Category.Reader

6767 Control.Category.Structures

6868 Data.Profunctor.Exposed

69− build-depends: base >= 4 && < 5, profunctors, transformers, lens, tuple-morph

69+ build-depends: base >= 4 && < 5, profunctors, transformers, lens, tuple-morph, semigroupoids

7070 default-language: Haskell2010

7171 ghc-options: -Wall