Safe Haskell	None
Language	Haskell2010

Control.Monad.Weighted.Filter

Description

This module provides a weighted monad which filters out zero-weighted results from a computation at every opportunity.

Synopsis

Documentation

data FilterT s m a Source #

A weighted monad which discards results which are zero as it goes.

Instances

(DetectableZero s, Alternative m, MonadError e m) => MonadError e (FilterT s m) Source #
Methods throwError :: e -> FilterT s m a # catchError :: FilterT s m a -> (e -> FilterT s m a) -> FilterT s m a #
(DetectableZero s, Alternative m, MonadReader r m) => MonadReader r (FilterT s m) Source #
Methods ask :: FilterT s m r # local :: (r -> r) -> FilterT s m a -> FilterT s m a # reader :: (r -> a) -> FilterT s m a #
(Alternative m, MonadState s m, DetectableZero w) => MonadState s (FilterT w m) Source #
Methods get :: FilterT w m s # put :: s -> FilterT w m () # state :: (s -> (a, s)) -> FilterT w m a #
(DetectableZero s, Alternative m, MonadWriter w m) => MonadWriter w (FilterT s m) Source #
Methods writer :: (a, w) -> FilterT s m a # tell :: w -> FilterT s m () # listen :: FilterT s m a -> FilterT s m (a, w) # pass :: FilterT s m (a, w -> w) -> FilterT s m a #
(DetectableZero w, Monad m, Alternative m) => MonadWeighted w (FilterT w m) Source #
Methods weighted :: (a, w) -> FilterT w m a Source # weight :: w -> FilterT w m () Source # weigh :: FilterT w m a -> FilterT w m (a, w) Source # scale :: FilterT w m (a, w -> w) -> FilterT w m a Source #
MonadTrans (FilterT s) Source #
Methods lift :: Monad m => m a -> FilterT s m a #
(Alternative m, Monad m, DetectableZero s) => Monad (FilterT s m) Source #
Methods (>>=) :: FilterT s m a -> (a -> FilterT s m b) -> FilterT s m b # (>>) :: FilterT s m a -> FilterT s m b -> FilterT s m b # return :: a -> FilterT s m a # fail :: String -> FilterT s m a #
(Alternative m, DetectableZero s) => Functor (FilterT s m) Source #
Methods fmap :: (a -> b) -> FilterT s m a -> FilterT s m b # (<$) :: a -> FilterT s m b -> FilterT s m a #
(DetectableZero s, Alternative m, MonadFix m) => MonadFix (FilterT s m) Source #
Methods mfix :: (a -> FilterT s m a) -> FilterT s m a #
(DetectableZero s, Alternative m, MonadFail m) => MonadFail (FilterT s m) Source #
Methods fail :: String -> FilterT s m a #
(Alternative m, Monad m, DetectableZero s) => Applicative (FilterT s m) Source #
Methods pure :: a -> FilterT s m a # (<>) :: FilterT s m (a -> b) -> FilterT s m a -> FilterT s m b # (>) :: FilterT s m a -> FilterT s m b -> FilterT s m b # (<*) :: FilterT s m a -> FilterT s m b -> FilterT s m a #
(Foldable m, DetectableZero w, Alternative m, Monad m) => Foldable (FilterT w m) Source #
Methods fold :: Monoid m => FilterT w m m -> m # foldMap :: Monoid m => (a -> m) -> FilterT w m a -> m # foldr :: (a -> b -> b) -> b -> FilterT w m a -> b # foldr' :: (a -> b -> b) -> b -> FilterT w m a -> b # foldl :: (b -> a -> b) -> b -> FilterT w m a -> b # foldl' :: (b -> a -> b) -> b -> FilterT w m a -> b # foldr1 :: (a -> a -> a) -> FilterT w m a -> a # foldl1 :: (a -> a -> a) -> FilterT w m a -> a # toList :: FilterT w m a -> [a] # null :: FilterT w m a -> Bool # length :: FilterT w m a -> Int # elem :: Eq a => a -> FilterT w m a -> Bool # maximum :: Ord a => FilterT w m a -> a # minimum :: Ord a => FilterT w m a -> a # sum :: Num a => FilterT w m a -> a # product :: Num a => FilterT w m a -> a #
(Traversable m, DetectableZero w, Alternative m, Monad m) => Traversable (FilterT w m) Source #
Methods traverse :: Applicative f => (a -> f b) -> FilterT w m a -> f (FilterT w m b) # sequenceA :: Applicative f => FilterT w m (f a) -> f (FilterT w m a) # mapM :: Monad m => (a -> m b) -> FilterT w m a -> m (FilterT w m b) # sequence :: Monad m => FilterT w m (m a) -> m (FilterT w m a) #
(Eq1 m, Eq w, DetectableZero w, Monad m, Alternative m) => Eq1 (FilterT w m) Source #
Methods liftEq :: (a -> b -> Bool) -> FilterT w m a -> FilterT w m b -> Bool #
(Ord1 m, Ord w, DetectableZero w, Monad m, Alternative m) => Ord1 (FilterT w m) Source #
Methods liftCompare :: (a -> b -> Ordering) -> FilterT w m a -> FilterT w m b -> Ordering #
(Read w, Read1 m, DetectableZero w, Alternative m, Monad m) => Read1 (FilterT w m) Source #
Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (FilterT w m a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [FilterT w m a] #
(Show w, Show1 m, DetectableZero w, Monad m, Alternative m) => Show1 (FilterT w m) Source #
Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> FilterT w m a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [FilterT w m a] -> ShowS #
(DetectableZero s, Alternative m, MonadIO m) => MonadIO (FilterT s m) Source #
Methods liftIO :: IO a -> FilterT s m a #
(DetectableZero s, MonadPlus m) => Alternative (FilterT s m) Source #
Methods empty :: FilterT s m a # (<\|>) :: FilterT s m a -> FilterT s m a -> FilterT s m a # some :: FilterT s m a -> FilterT s m [a] # many :: FilterT s m a -> FilterT s m [a] #
(DetectableZero s, MonadPlus m) => MonadPlus (FilterT s m) Source #
Methods mzero :: FilterT s m a # mplus :: FilterT s m a -> FilterT s m a -> FilterT s m a #
(DetectableZero s, Alternative m, MonadCont m) => MonadCont (FilterT s m) Source #
Methods callCC :: ((a -> FilterT s m b) -> FilterT s m a) -> FilterT s m a #
(Eq w, Eq1 m, Eq a, DetectableZero w, Monad m, Alternative m) => Eq (FilterT w m a) Source #
Methods (==) :: FilterT w m a -> FilterT w m a -> Bool # (/=) :: FilterT w m a -> FilterT w m a -> Bool #
(Ord w, Ord1 m, Ord a, DetectableZero w, Monad m, Alternative m) => Ord (FilterT w m a) Source #
Methods compare :: FilterT w m a -> FilterT w m a -> Ordering # (<) :: FilterT w m a -> FilterT w m a -> Bool # (<=) :: FilterT w m a -> FilterT w m a -> Bool # (>) :: FilterT w m a -> FilterT w m a -> Bool # (>=) :: FilterT w m a -> FilterT w m a -> Bool # max :: FilterT w m a -> FilterT w m a -> FilterT w m a # min :: FilterT w m a -> FilterT w m a -> FilterT w m a #
(Read w, Read1 m, Read a, DetectableZero w, Alternative m, Monad m) => Read (FilterT w m a) Source #
Methods readsPrec :: Int -> ReadS (FilterT w m a) # readList :: ReadS [FilterT w m a] # readPrec :: ReadPrec (FilterT w m a) # readListPrec :: ReadPrec [FilterT w m a] #
(Show w, Show1 m, Show a, DetectableZero w, Alternative m, Monad m) => Show (FilterT w m a) Source #
Methods showsPrec :: Int -> FilterT w m a -> ShowS # show :: FilterT w m a -> String # showList :: [FilterT w m a] -> ShowS #

pattern FilterT :: forall m s a. (Alternative m, DetectableZero s, Monad m) => m (a, s) -> FilterT s m a Source #

This pattern gives an interface to the FilterT monad which makes it look as if it were defined without the state monad.

runFilterT :: (DetectableZero s, Alternative m, Monad m) => FilterT s m a -> m (a, s) Source #

Run a filtered computation in the underlying monad.

evalFilterT :: (Monad m, Semiring s) => FilterT s m a -> m a Source #

Evaluate a filtered computation in the underlying monad and return its result.

execFilterT :: (Monad m, Semiring s) => FilterT s m a -> m s Source #

Evaluate a filtered computation in the underlying monad and collect its weight.