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mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()mixed-types-num Numeric.MixedTypes.PreludeHiding 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.
mapM_ :: Monad m => (a -> m b) -> NonEmptyVector a -> m ()nonempty-vector Data.Vector.NonEmpty O(n) Apply the monadic action to all elements of a non-empty vector and ignore the results.
>>> mapM_ (const $ Just ()) (unsafeFromList [1..3]) Just ()
>>> mapM_ (const Nothing) (unsafeFromList [1..3]) Nothing
mapMaybe :: (a -> Maybe b) -> NonEmptyVector a -> Vector bnonempty-vector Data.Vector.NonEmpty O(n) Drop elements when predicate returns Nothing If no elements satisfy the predicate, the resulting vector may be empty.
>>> mapMaybe (\a -> if a == 2 then Nothing else Just a) (unsafeFromList [1..3]) [1,3]
mapMLazy :: PrimBase m => (a -> m b) -> [a] -> m [b]simple-cairo Graphics.Cairo.Drawing.CairoPatternT.Mesh No documentation available.
mapMaybeReversed :: (a -> Maybe b) -> List a -> List bstrict-list StrictList Map and filter elements producing results in reversed order.
mapM_ :: (Foldable t, Monad m) => (a -> m ()) -> t a -> m ()LambdaHack Game.LambdaHack.Core.Prelude This has a more specific type (unit result) than normally, to catch errors.
mapMaybe :: List l => (a -> Maybe b) -> l a -> l bList Data.List.Class No documentation available.
mapMaybe :: (a -> Maybe b) -> Trie a -> Maybe (Trie b)bcp47 Data.BCP47.Trie No documentation available.
mapMaybe :: (a -> Maybe b) -> Trie a -> Maybe (Trie b)bcp47 Data.BCP47.Trie.Internal No documentation available.
mapMaybe2 :: (a -> Maybe b) -> Trie2 a -> Maybe (Trie2 b)bcp47 Data.BCP47.Trie.Internal No documentation available.