control-monad-free-0.6.1: Free monads and monad transformers

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LanguageHaskell98

Control.Monad.Free

Contents

Synopsis

Documentation

Free Monads

class (Functor f, Monad m) => MonadFree f m where #

This type class generalizes over encodings of Free Monads.

Minimal complete definition

free, wrap

Methods

free :: m a -> m (Either a (f (m a))) #

wrap :: f (m a) -> m a #

Instances

Functor f => MonadFree f (Free f) # 

Methods

free :: Free f a -> Free f (Either a (f (Free f a))) #

wrap :: f (Free f a) -> Free f a #

(Monad m, Functor f) => MonadFree f (C (FreeT f m)) # 

Methods

free :: C (FreeT f m) a -> C (FreeT f m) (Either a (f (C (FreeT f m) a))) #

wrap :: f (C (FreeT f m) a) -> C (FreeT f m) a #

Functor f => MonadFree f (C (Free f)) # 

Methods

free :: C (Free f) a -> C (Free f) (Either a (f (C (Free f) a))) #

wrap :: f (C (Free f) a) -> C (Free f) a #

(Functor f, Monad m) => MonadFree f (FreeT f m) # 

Methods

free :: FreeT f m a -> FreeT f m (Either a (f (FreeT f m a))) #

wrap :: f (FreeT f m a) -> FreeT f m a #

data Free f a #

Constructors

Impure (f (Free f a)) 
Pure a 

Instances

Functor f => MonadFree f (Free f) # 

Methods

free :: Free f a -> Free f (Either a (f (Free f a))) #

wrap :: f (Free f a) -> Free f a #

Functor f => MonadFree f (C (Free f)) # 

Methods

free :: C (Free f) a -> C (Free f) (Either a (f (C (Free f) a))) #

wrap :: f (C (Free f) a) -> C (Free f) a #

Functor f => Monad (Free f) # 

Methods

(>>=) :: Free f a -> (a -> Free f b) -> Free f b #

(>>) :: Free f a -> Free f b -> Free f b #

return :: a -> Free f a #

fail :: String -> Free f a #

Functor f => Functor (Free f) # 

Methods

fmap :: (a -> b) -> Free f a -> Free f b #

(<$) :: a -> Free f b -> Free f a #

Functor f => Applicative (Free f) # 

Methods

pure :: a -> Free f a #

(<*>) :: Free f (a -> b) -> Free f a -> Free f b #

(*>) :: Free f a -> Free f b -> Free f b #

(<*) :: Free f a -> Free f b -> Free f a #

(Functor f, Foldable f) => Foldable (Free f) # 

Methods

fold :: Monoid m => Free f m -> m #

foldMap :: Monoid m => (a -> m) -> Free f a -> m #

foldr :: (a -> b -> b) -> b -> Free f a -> b #

foldr' :: (a -> b -> b) -> b -> Free f a -> b #

foldl :: (b -> a -> b) -> b -> Free f a -> b #

foldl' :: (b -> a -> b) -> b -> Free f a -> b #

foldr1 :: (a -> a -> a) -> Free f a -> a #

foldl1 :: (a -> a -> a) -> Free f a -> a #

toList :: Free f a -> [a] #

null :: Free f a -> Bool #

length :: Free f a -> Int #

elem :: Eq a => a -> Free f a -> Bool #

maximum :: Ord a => Free f a -> a #

minimum :: Ord a => Free f a -> a #

sum :: Num a => Free f a -> a #

product :: Num a => Free f a -> a #

Traversable f => Traversable (Free f) # 

Methods

traverse :: Applicative f => (a -> f b) -> Free f a -> f (Free f b) #

sequenceA :: Applicative f => Free f (f a) -> f (Free f a) #

mapM :: Monad m => (a -> m b) -> Free f a -> m (Free f b) #

sequence :: Monad m => Free f (m a) -> m (Free f a) #

Eq1 f => Eq1 (Free f) # 

Methods

(==#) :: Eq a => Free f a -> Free f a -> Bool #

Ord1 f => Ord1 (Free f) # 

Methods

compare1 :: Ord a => Free f a -> Free f a -> Ordering #

(Eq a, Eq1 f) => Eq (Free f a) # 

Methods

(==) :: Free f a -> Free f a -> Bool #

(/=) :: Free f a -> Free f a -> Bool #

(Ord a, Ord1 f) => Ord (Free f a) # 

Methods

compare :: Free f a -> Free f a -> Ordering #

(<) :: Free f a -> Free f a -> Bool #

(<=) :: Free f a -> Free f a -> Bool #

(>) :: Free f a -> Free f a -> Bool #

(>=) :: Free f a -> Free f a -> Bool #

max :: Free f a -> Free f a -> Free f a #

min :: Free f a -> Free f a -> Free f a #

(Show a, Show1 f) => Show (Free f a) # 

Methods

showsPrec :: Int -> Free f a -> ShowS #

show :: Free f a -> String #

showList :: [Free f a] -> ShowS #

Generic (Free f a) # 

Associated Types

type Rep (Free f a) :: * -> * #

Methods

from :: Free f a -> Rep (Free f a) x #

to :: Rep (Free f a) x -> Free f a #

type Rep (Free f a) # 
type Rep (Free f a) = D1 (MetaData "Free" "Control.Monad.Free" "control-monad-free-0.6.1-6sHLlBhFKrC1QUKEf8Gbv7" False) ((:+:) (C1 (MetaCons "Impure" PrefixI False) (S1 (MetaSel (Nothing Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (f (Free f a))))) (C1 (MetaCons "Pure" PrefixI False) (S1 (MetaSel (Nothing Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a))))

isPure :: Free t1 t -> Bool #

isImpure :: Free t1 t -> Bool #

foldFree :: Functor f => (a -> b) -> (f b -> b) -> Free f a -> b #

evalFree :: (a -> b) -> (f (Free f a) -> b) -> Free f a -> b #

mapFree :: (Functor f, Functor g) => (f (Free g a) -> g (Free g a)) -> Free f a -> Free g a #

mapFreeM :: (Traversable f, Functor g, Monad m) => (f (Free g a) -> m (g (Free g a))) -> Free f a -> m (Free g a) #

mapFreeM' :: (Functor f, Traversable g, Monad m) => (forall a. f a -> m (g a)) -> Free f a -> m (Free g a) #

Monad Morphisms

foldFreeM :: (Traversable f, Monad m) => (a -> m b) -> (f b -> m b) -> Free f a -> m b #

induce :: (Functor f, Monad m) => (forall a. f a -> m a) -> Free f a -> m a #

Free Monad Transformers

newtype FreeT f m a #

Constructors

FreeT 

Fields

Instances

(Monad m, Functor f) => MonadFree f (C (FreeT f m)) # 

Methods

free :: C (FreeT f m) a -> C (FreeT f m) (Either a (f (C (FreeT f m) a))) #

wrap :: f (C (FreeT f m) a) -> C (FreeT f m) a #

(Functor f, Monad m) => MonadFree f (FreeT f m) # 

Methods

free :: FreeT f m a -> FreeT f m (Either a (f (FreeT f m a))) #

wrap :: f (FreeT f m a) -> FreeT f m a #

Functor f => MonadTrans (FreeT f) # 

Methods

lift :: Monad m => m a -> FreeT f m a #

(Functor f, Monad m) => Monad (FreeT f m) # 

Methods

(>>=) :: FreeT f m a -> (a -> FreeT f m b) -> FreeT f m b #

(>>) :: FreeT f m a -> FreeT f m b -> FreeT f m b #

return :: a -> FreeT f m a #

fail :: String -> FreeT f m a #

(Functor f, Functor m) => Functor (FreeT f m) # 

Methods

fmap :: (a -> b) -> FreeT f m a -> FreeT f m b #

(<$) :: a -> FreeT f m b -> FreeT f m a #

(Functor f, Functor a, Monad a) => Applicative (FreeT f a) # 

Methods

pure :: a -> FreeT f a a #

(<*>) :: FreeT f a (a -> b) -> FreeT f a a -> FreeT f a b #

(*>) :: FreeT f a a -> FreeT f a b -> FreeT f a b #

(<*) :: FreeT f a a -> FreeT f a b -> FreeT f a a #

(Traversable m, Traversable f) => Foldable (FreeT f m) # 

Methods

fold :: Monoid m => FreeT f m m -> m #

foldMap :: Monoid m => (a -> m) -> FreeT f m a -> m #

foldr :: (a -> b -> b) -> b -> FreeT f m a -> b #

foldr' :: (a -> b -> b) -> b -> FreeT f m a -> b #

foldl :: (b -> a -> b) -> b -> FreeT f m a -> b #

foldl' :: (b -> a -> b) -> b -> FreeT f m a -> b #

foldr1 :: (a -> a -> a) -> FreeT f m a -> a #

foldl1 :: (a -> a -> a) -> FreeT f m a -> a #

toList :: FreeT f m a -> [a] #

null :: FreeT f m a -> Bool #

length :: FreeT f m a -> Int #

elem :: Eq a => a -> FreeT f m a -> Bool #

maximum :: Ord a => FreeT f m a -> a #

minimum :: Ord a => FreeT f m a -> a #

sum :: Num a => FreeT f m a -> a #

product :: Num a => FreeT f m a -> a #

(Traversable m, Traversable f) => Traversable (FreeT f m) # 

Methods

traverse :: Applicative f => (a -> f b) -> FreeT f m a -> f (FreeT f m b) #

sequenceA :: Applicative f => FreeT f m (f a) -> f (FreeT f m a) #

mapM :: Monad m => (a -> m b) -> FreeT f m a -> m (FreeT f m b) #

sequence :: Monad m => FreeT f m (m a) -> m (FreeT f m a) #

(Functor f, Monad m, MonadIO m) => MonadIO (FreeT f m) # 

Methods

liftIO :: IO a -> FreeT f m a #

(Functor f, Functor m, Monad m, MonadPlus m) => Alternative (FreeT f m) # 

Methods

empty :: FreeT f m a #

(<|>) :: FreeT f m a -> FreeT f m a -> FreeT f m a #

some :: FreeT f m a -> FreeT f m [a] #

many :: FreeT f m a -> FreeT f m [a] #

(Functor f, Monad m, MonadPlus m) => MonadPlus (FreeT f m) # 

Methods

mzero :: FreeT f m a #

mplus :: FreeT f m a -> FreeT f m a -> FreeT f m a #

foldFreeT :: (Traversable f, Monad m) => (a -> m b) -> (f b -> m b) -> FreeT f m a -> m b #

foldFreeT' :: (Traversable f, Monad m) => (a -> b) -> (f b -> b) -> FreeT f m a -> m b #

mapFreeT :: (Functor f, Functor m) => (forall a. m a -> m' a) -> FreeT f m a -> FreeT f m' a #

foldFreeA :: (Traversable f, Applicative m) => (a -> m b) -> m (f b -> b) -> Free f a -> m b #

mapFreeA :: (Traversable f, Functor g, Applicative m) => m (f (Free g a) -> g (Free g a)) -> Free f a -> m (Free g a) #

Translate between Free monad and Free monad transformer computations

trans :: MonadFree f m => Free f a -> m a #

trans' :: (Functor f, Monad m) => m (Free f a) -> FreeT f m a #

untrans :: (Traversable f, Monad m) => FreeT f m a -> m (Free f a) #

liftFree :: (Functor f, Monad m) => (a -> Free f b) -> a -> FreeT f m b #