monadic-recursion-schemes 0.1.0.0 → 0.1.1.0

raw patch · 2 files changed

+62/−21 lines, 2 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• monadic-recursion-schemes.cabal +1/−1
• src/Data/Functor/Foldable/Monadic.hs +61/−20

@@ -4,7 +4,7 @@ -- http://haskell.org/cabal/users-guide/  name:                monadic-recursion-schemes-version:             0.1.0.0+version:             0.1.1.0 synopsis:            Recursion Schemes for Monadic version. description:         Yet another recursion schemes for monadic style, depends on recursion-schemes. homepage:            https://github.com/cutsea110/monadic-recursion-schemes.git

@@ -7,62 +7,103 @@   ( cataM, anaM   , paraM, apoM   , histoM, futuM+  , histoM', futuM'   , zygoM, cozygoM   , hyloM   ) where -import           Control.Comonad            (Comonad (..))-import           Control.Comonad.Cofree     (Cofree (..))-import           Control.Monad              ((<=<), liftM2)-import           Control.Monad.Free         (Free (..))-import           Control.Monad.Trans.Class  (lift)-import           Control.Monad.Trans.Reader (ReaderT, ask, runReaderT)-import           Data.Functor.Foldable      (Recursive (..), Corecursive (..), Base, Fix (..))+import           Control.Comonad              (Comonad (..))+import           Control.Comonad.Cofree       (Cofree (..))+import qualified Control.Comonad.Trans.Cofree as Cf (CofreeF (..))+import           Control.Monad                ((<=<), liftM2)+import           Control.Monad.Free           (Free (..))+import qualified Control.Monad.Trans.Free     as Fr (FreeF (..))+import           Control.Monad.Trans.Class    (lift)+import           Control.Monad.Trans.Reader   (ReaderT, ask, runReaderT)+import           Data.Functor.Foldable        (Recursive (..), Corecursive (..), Base, Fix (..))  +-- | catamorphism cataM :: (Monad m, Traversable (Base t), Recursive t)-      => (Base t a -> m a) -> t -> m a+      => (Base t a -> m a) -- ^ algebra+      -> t -> m a cataM phi = h   where h = phi <=< mapM h . project +-- | anamorphism anaM :: (Monad m, Traversable (Base t), Corecursive t)-     => (a -> m (Base t a)) -> a -> m t+     => (a -> m (Base t a)) -- ^ coalgebra+     -> a -> m t anaM psi = h   where h = (return . embed) <=< mapM h <=< psi +-- | paramorphism paraM :: (Monad m, Traversable (Base t), Recursive t)-      => (Base t (t, a) -> m a) -> t -> m a+      => (Base t (t, a) -> m a) -- ^ algebra+      -> t -> m a paraM phi = h   where h = phi <=< mapM (liftM2 (,) <$> return <*> h) . project +-- | apomorphism apoM :: (Monad m, Traversable (Base t), Corecursive t)-     => (a -> m (Base t (Either t a))) -> a -> m t+     => (a -> m (Base t (Either t a))) -- ^ coalgebra+     -> a -> m t apoM psi = h   where h = (return . embed) <=< mapM (either return h) <=< psi +-- | histomorphism on recursion variant histoM :: (Monad m, Traversable (Base t), Recursive t)-       => (Base t (Cofree (Base t) a) -> m a) -> t -> m a-histoM phi = return . extract <=< cataM f-  where f  = return . uncurry (:<) <=< (liftM2 (,) <$> phi <*> return)+       => (Base t (Cofree (Base t) a) -> m a) -- ^ algebra+       -> t -> m a+histoM phi = h+  where h = phi <=< mapM f . project+        f = anaM (liftM2 (Cf.:<) <$> h <*> (return . project)) +-- | histomorphism on catamorphism variant+histoM' :: (Monad m, Traversable (Base t), Recursive t)+        => (Base t (Cofree (Base t) a) -> m a)+        -> t -> m a+histoM' phi = return . extract <=< cataM f+  where f = return . uncurry (:<) <=< (liftM2 (,) <$> phi <*> return)++-- | futumorphism on recursion variant futuM :: (Monad m, Traversable (Base t), Corecursive t)-      => (a -> m (Base t (Free (Base t) a))) -> a -> m t-futuM psi = anaM f . Pure+      => (a -> m (Base t (Free (Base t) a))) -- ^ coalgebra+      -> a -> m t+futuM psi = h+  where h = (return . embed) <=< mapM f <=< psi+        f = cataM $ \case+          Fr.Pure  a -> h a+          Fr.Free fb -> return (embed fb)++-- | futumorphism on anamorphism variant+futuM' :: (Monad m, Traversable (Base t), Corecursive t)+      => (a -> m (Base t (Free (Base t) a))) -- ^ coalgebra+      -> a -> m t+futuM' psi = anaM f . Pure   where f (Pure  a) = psi a         f (Free fb) = return fb +-- | zygomorphism zygoM :: (Monad m, Traversable (Base t), Recursive t)-      => (Base t a -> m a) -> (Base t (a, b) -> m b) -> t -> m b+      => (Base t a -> m a)      -- ^ algebra for fst+      -> (Base t (a, b) -> m b) -- ^ algebra for snd from product+      -> t -> m b zygoM f phi = return . snd <=< cataM g   where g = liftM2 (,) <$> (f <=< return . fmap fst) <*> phi +-- | cozygomorphism cozygoM :: (Monad m, Traversable (Base t), Corecursive t)-        => (a -> m (Base t a)) -> (b -> m (Base t (Either a b))) -> b -> m t+        => (a -> m (Base t a))            -- ^ coalgebra for fst+        -> (b -> m (Base t (Either a b))) -- ^ coalgebra for snd to coproduct+        -> b -> m t cozygoM f psi = anaM g . Right   where g = either (return . fmap Left <=< f) psi +-- | hylomorphism hyloM :: (Monad m, Traversable t)-      => (t b -> m b) -> (a -> m (t a)) -> a -> m b+      => (t b -> m b)   -- ^ algebra+      -> (a -> m (t a)) -- ^ coalgebra+      -> a -> m b hyloM phi psi = h   where h = phi <=< mapM h <=< psi-