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1. mapM :: (Traversable t, Monad m) => (a -> m b) -> t a -> m (t b)

   classy-prelude-yesod	ClassyPrelude.Yesod

   Map each element of a structure to a monadic action, evaluate these actions from left to right, and collect the results. For a version that ignores the results see mapM_.

   Examples

   mapM is literally a traverse with a type signature restricted to Monad. Its implementation may be more efficient due to additional power of Monad.

2. mapMC :: Monad m => (a -> m b) -> ConduitT a b m ()

   classy-prelude-yesod	ClassyPrelude.Yesod

   Apply a monadic transformation to all values in a stream. If you do not need the transformed values, and instead just want the monadic side-effects of running the action, see mapM_.

3. mapMCE :: (Monad m, Traversable f) => (a -> m b) -> ConduitT (f a) (f b) m ()

   classy-prelude-yesod	ClassyPrelude.Yesod

   Apply a monadic transformation to all elements in a chunked stream.

4. mapM_ :: (MonoFoldable mono, Applicative m) => (Element mono -> m ()) -> mono -> m ()

   classy-prelude-yesod	ClassyPrelude.Yesod

   Synonym for omapM_

5. mapM_C :: Monad m => (a -> m ()) -> ConduitT a o m ()

   classy-prelude-yesod	ClassyPrelude.Yesod

   Apply the action to all values in the stream. Note: if you want to pass the values instead of consuming them, use iterM instead.

6. mapM_CE :: (Monad m, MonoFoldable mono) => (Element mono -> m ()) -> ConduitT mono o m ()

   classy-prelude-yesod	ClassyPrelude.Yesod

   Apply the action to all elements in the chunked stream. Note: the same caveat as with mapM_C applies. If you don't want to consume the values, you can use iterM:

   iterM (omapM_ f)
   

7. mapMaybe :: (a -> Maybe b) -> [a] -> [b]

   classy-prelude-yesod	ClassyPrelude.Yesod

   The mapMaybe function is a version of map which can throw out elements. In particular, the functional argument returns something of type Maybe b. If this is Nothing, no element is added on to the result list. If it is Just b, then b is included in the result list.

   Examples

   Using mapMaybe f x is a shortcut for catMaybes $ map f x in most cases:

   >>> import GHC.Internal.Text.Read ( readMaybe )
   
   >>> let readMaybeInt = readMaybe :: String -> Maybe Int
   
   >>> mapMaybe readMaybeInt ["1", "Foo", "3"]
   [1,3]
   
   >>> catMaybes $ map readMaybeInt ["1", "Foo", "3"]
   [1,3]
   

   If we map the Just constructor, the entire list should be returned:

   >>> mapMaybe Just [1,2,3]
   [1,2,3]
   

8. mapNonNull :: (Functor f, MonoFoldable (f b)) => (a -> b) -> NonNull (f a) -> NonNull (f b)

   classy-prelude-yesod	ClassyPrelude.Yesod

   fmap over the underlying container in a NonNull.

9. mapOutput :: forall (m :: Type -> Type) o1 o2 i r . Monad m => (o1 -> o2) -> ConduitT i o1 m r -> ConduitT i o2 m r

   classy-prelude-yesod	ClassyPrelude.Yesod

   Apply a function to all the output values of a ConduitT. This mimics the behavior of fmap for a Source and Conduit in pre-0.4 days. It can also be simulated by fusing with the map conduit from Data.Conduit.List. Since 0.4.1

10. mapOutputMaybe :: forall (m :: Type -> Type) o1 o2 i r . Monad m => (o1 -> Maybe o2) -> ConduitT i o1 m r -> ConduitT i o2 m r

    classy-prelude-yesod	ClassyPrelude.Yesod

    Same as mapOutput, but use a function that returns Maybe values. Since 0.5.0

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