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1. mapMaybe :: (MonadGen m, GenBase m ~ Identity) => (a -> Maybe b) -> m a -> m b

   hedgehog	Hedgehog.Internal.Gen

   Generates a value which is the result of the given function returning a Just. The original generator's shrink tree will be retained, with values returning Nothing removed. Subsequent shrinks of those values will be retained. Compared to mapMaybeT, shrinking may be slower but will be optimal. It's possible that the function will never return Just, or will only do so a larger size than we're currently running at. To avoid looping forever, we limit the number of retries, and grow the size with each retry. If we retry too many times then the whole generator is discarded.

2. mapMaybeT :: MonadGen m => (a -> Maybe b) -> m a -> m b

   hedgehog	Hedgehog.Internal.Gen

   Generates a value which is the result of the given function returning a Just. The original generator's shrink tree will be retained, with values returning Nothing removed. Subsequent shrinks of those values will be retained. Compared to mapMaybeT, shrinking may be slower but will be optimal. The type is also more general, because the shrink behavior from mapMaybe would force the entire shrink tree to be evaluated when applied to an impure tree. It's possible that the function will never return Just, or will only do so a larger size than we're currently running at. To avoid looping forever, we limit the number of retries, and grow the size with each retry. If we retry too many times then the whole generator is discarded.

3. 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.

4. mapMaybe :: (a -> Maybe b) -> Tree a -> Maybe (Tree b)

   hedgehog	Hedgehog.Internal.Tree

   No documentation available.

5. mapMaybeMaybeT :: (a -> Maybe b) -> TreeT (MaybeT Identity) a -> TreeT (MaybeT Identity) b

   hedgehog	Hedgehog.Internal.Tree

   No documentation available.

6. mapMaybeT :: forall (m :: Type -> Type) a b . (Monad m, Alternative m) => (a -> Maybe b) -> TreeT m a -> TreeT m b

   hedgehog	Hedgehog.Internal.Tree

   No documentation available.

7. mapMOf :: LensLike (WrappedMonad m) s t a b -> (a -> m b) -> s -> m t

   microlens	Lens.Micro

   Map each element of a structure targeted by a Lens to a monadic action, evaluate these actions from left to right, and collect the results.

   >>> mapMOf both (\x -> [x, x + 1]) (1,3)
   [(1,3),(1,4),(2,3),(2,4)]
   

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

   extra	Control.Monad.Extra

   A version of mapMaybe that works with a monadic predicate.

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

   extra	Extra

   A version of mapMaybe that works with a monadic predicate.

10. mapM_ :: Monad m => (Word8 -> m ()) -> ConduitT ByteString o m ()

    conduit-extra	Data.Conduit.Binary

    Perform a computation on each Word8 in a stream. Since 1.0.10

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