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1. concatMapM :: (Monad m, Traversable f) => (a -> m [b]) -> f a -> m [b]

   ghc	GHC.Utils.Monad

   Monadic version of concatMap

2. comapM :: (Distributive g, Monad m) => (m a -> b) -> m (g a) -> g b

   distributive	Data.Distributive

   The dual of mapM

   comapM f = fmap f . distributeM
   

3. imapM_ :: (FoldableWithIndex i t, Monad m) => (i -> a -> m b) -> t a -> m ()

   indexed-traversable	Data.Foldable.WithIndex

   Run monadic actions for each target of an IndexedFold or IndexedTraversal with access to the index, discarding the results. When you don't need access to the index then mapMOf_ is more flexible in what it accepts.

   mapM_ ≡ imapM . const
   

4. imapM :: (TraversableWithIndex i t, Monad m) => (i -> a -> m b) -> t a -> m (t b)

   indexed-traversable	Data.Traversable.WithIndex

   Map each element of a structure to a monadic action, evaluate these actions from left to right, and collect the results, with access the index. When you don't need access to the index mapM is more liberal in what it can accept.

   mapM ≡ imapM . const
   

5. postmapM :: Monad m => (a -> m r) -> FoldM m x a -> FoldM m x r

   foldl	Control.Foldl

   (postmapM f folder) returns a new FoldM where f is applied to the final value.

   postmapM pure = id
   
   postmapM (f >=> g) = postmapM g . postmapM f
   

   postmapM k (pure r) = lifts (k r)
   

6. premapM :: Monad m => (a -> m b) -> FoldM m b r -> FoldM m a r

   foldl	Control.Foldl

   (premapM f folder) returns a new FoldM where f is applied to each input element

   premapM return = id
   
   premapM (f <=< g) = premap g . premap f
   

   premapM k (pure r) = pure r
   
   premapM k (f <*> x) = premapM k f <*> premapM k x
   

7. premapM :: Monad m => (a -> m b) -> ScanM m b r -> ScanM m a r

   foldl	Control.Scanl

   (premapM f scaner) returns a new ScanM where f is applied to each input element

   premapM return = id
   
   premapM (f <=< g) = premap g . premap f
   

   premapM k (pure r) = pure r
   
   premapM k (f <*> x) = premapM k f <*> premapM k x
   

8. intMapMaybe :: Int -> T (IntMap elem) (Maybe elem)

   data-accessor	Data.Accessor.Container

   No documentation available.

9. gmapM :: (GTraversable t, Monad m) => (a -> m b) -> t a -> m (t b)

   generic-deriving	Generics.Deriving.Traversable

   No documentation available.

10. contramapM :: (a -> IO b) -> OutputStream b -> IO (OutputStream a)

    io-streams	System.IO.Streams.Combinators

    Contravariant counterpart to mapM. contramapM f s passes all input to s through the IO action f Satisfies the following laws:

    Streams.contramapM (f >=> g) = Streams.contramapM g >=> Streams.contramapM f
    Streams.contramapM return = return
    

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