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Within LTS Haskell 24.32 (ghc-9.10.3)

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1. evalMaybe :: (MonadTest m, HasCallStack) => Maybe a -> m a

   hedgehog	Hedgehog.Internal.Property

   Fails the test if the Maybe is Nothing, otherwise returns the value in the Just.

2. evalMaybeM :: (MonadTest m, MonadCatch m, HasCallStack) => m (Maybe a) -> m a

   hedgehog	Hedgehog.Internal.Property

   Fails the test if the action throws an exception, or if the Maybe is Nothing, otherwise returns the value in the Just.

3. catMaybes :: Tree (Maybe a) -> Maybe (Tree a)

   hedgehog	Hedgehog.Internal.Tree

   Takes a tree of Maybes and returns a tree of all the Just values. If the root of the tree is Nothing then Nothing is returned.

4. filterMaybeT :: (a -> Bool) -> TreeT (MaybeT Identity) a -> TreeT (MaybeT Identity) a

   hedgehog	Hedgehog.Internal.Tree

   Returns a tree containing only elements that match the predicate. If the root of the tree does not match the predicate then Nothing is returned.

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

   hedgehog	Hedgehog.Internal.Tree

   No documentation available.

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

   hedgehog	Hedgehog.Internal.Tree

   No documentation available.

7. 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.

8. parseMaybe :: (Ord e, Stream s) => Parsec e s a -> s -> Maybe a

   megaparsec	Text.Megaparsec

   parseMaybe p input runs the parser p on input and returns the result inside Just on success and Nothing on failure. This function also parses eof, so if the parser doesn't consume all of its input, it will fail. The function is supposed to be useful for lightweight parsing, where error messages (and thus file names) are not important and entire input should be consumed. For example, it can be used for parsing of a single number according to a specification of its format.

9. waitBarrierMaybe :: Barrier a -> IO (Maybe a)

   extra	Control.Concurrent.Extra

   A version of waitBarrier that never blocks, returning Nothing if the barrier has not yet been signaled.

10. fromMaybeM :: Monad m => m a -> m (Maybe a) -> m a

    extra	Control.Monad.Extra

    Monadic generalisation of fromMaybe.

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