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mapM :: (Traversable t, Monad m) => (a -> m b) -> t a -> m (t b)base 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.mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()base 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.
mappend :: Monoid a => a -> a -> abase 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.
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gogol-core Gogol.Prelude mapM :: (Traversable t, Monad m) => (a -> m b) -> t a -> m (t b)hedgehog Hedgehog.Internal.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.mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()hedgehog Hedgehog.Internal.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.
mappend :: Monoid a => a -> a -> ahedgehog Hedgehog.Internal.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.
mapM :: (Traversable t, Monad m) => (a -> m b) -> t a -> m (t b)ghc GHC.Prelude.Basic No documentation available.
mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()ghc GHC.Prelude.Basic No documentation available.
mappend :: Monoid a => a -> a -> aghc GHC.Prelude.Basic No documentation available.