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mapM :: (Traversable t, Monad m) => (a -> m b) -> t a -> m (t b)prelude-compat Prelude2010 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.mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()prelude-compat Prelude2010 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.
mapLeft :: Bifunctor p => (a -> b) -> p a c -> p b crebase Rebase.Data.Bifunctor A more meaningful and conflict-free alias for first.
mapRight :: Bifunctor p => (b -> c) -> p a b -> p a crebase Rebase.Data.Bifunctor A more meaningful and conflict-free alias for second.
mapM :: Monad m => (a -> m b) -> Vector a -> m (Vector b)rebase Rebase.Data.Vector No documentation available.
mapM_ :: Monad m => (a -> m b) -> Vector a -> m ()rebase Rebase.Data.Vector No documentation available.
mapMaybe :: (a -> Maybe b) -> Vector a -> Vector brebase Rebase.Data.Vector No documentation available.
mapMaybeM :: Monad m => (a -> m (Maybe b)) -> Vector a -> m (Vector b)rebase Rebase.Data.Vector No documentation available.
mapM :: Monad m => (a -> m b) -> Stream m a -> Stream m brebase Rebase.Data.Vector.Fusion.Stream.Monadic Map a monadic function over a Stream
mapM_ :: Monad m => (a -> m b) -> Stream m a -> m ()rebase Rebase.Data.Vector.Fusion.Stream.Monadic Execute a monadic action for each element of the Stream