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

   distribution-opensuse	OpenSuse.Prelude

   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. mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()

   distribution-opensuse	OpenSuse.Prelude

   Map each element of a structure to a monadic action, evaluate these actions from left to right, and ignore the results. For a version that doesn't ignore the results see mapM. mapM_ is just like traverse_, but specialised to monadic actions.

3. mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()

   distribution-opensuse	OpenSuse.Prelude

   Map each element of a structure to a monadic action, evaluate these actions from left to right, and ignore the results. For a version that doesn't ignore the results see mapM. mapM_ is just like traverse_, but specialised to monadic actions.

4. mapMaybeM :: Monad m => (a -> m (Maybe b)) -> [a] -> m [b]

   distribution-opensuse	OpenSuse.Prelude

   A version of mapMaybe that works with a monadic predicate.

5. mappend :: Monoid a => a -> a -> a

   distribution-opensuse	OpenSuse.Prelude

   An associative operation NOTE: This method is redundant and has the default implementation mappend = (<>) since base-4.11.0.0. Should it be implemented manually, since mappend is a synonym for (<>), it is expected that the two functions are defined the same way. In a future GHC release mappend will be removed from Monoid.

6. mappend :: Monoid a => a -> a -> a

   distribution-opensuse	OpenSuse.Prelude

   An associative operation NOTE: This method is redundant and has the default implementation mappend = (<>) since base-4.11.0.0. Should it be implemented manually, since mappend is a synonym for (<>), it is expected that the two functions are defined the same way. In a future GHC release mappend will be removed from Monoid.

7. mapExcept :: (Either e a -> Either e' b) -> Except e a -> Except e' b

   dunai	Control.Monad.Trans.MSF.Except

   Map the unwrapped computation using the given function.

   • runExcept (mapExcept f m) = f (runExcept
     m)

8. mapExceptT :: (m (Either e a) -> n (Either e' b)) -> ExceptT e m a -> ExceptT e' n b

   dunai	Control.Monad.Trans.MSF.Except

   Map the unwrapped computation using the given function.

   • runExceptT (mapExceptT f m) = f
     (runExceptT m)

9. mapMSF :: forall (m :: Type -> Type) a b . Monad m => MSF m a b -> MSF m [a] [b]

   dunai	Control.Monad.Trans.MSF.List

   Apply an MSF to every input.

10. mapMaybeT :: (m (Maybe a) -> n (Maybe b)) -> MaybeT m a -> MaybeT n b

    dunai	Control.Monad.Trans.MSF.Maybe

    Transform the computation inside a MaybeT.

    • runMaybeT (mapMaybeT f m) = f (runMaybeT
      m)

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