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1. mapMaybeWithKey :: (Build1 -> a -> Maybe b) -> Radix1Tree a -> Radix1Tree b

   radix-tree	Data.Radix1Tree.Word8.Lazy

   Apply a function to every value in the tree and create one out of Just values.

2. mapMaybe :: (a -> Maybe b) -> Radix1Tree a -> Radix1Tree b

   radix-tree	Data.Radix1Tree.Word8.Strict

   Apply a function to every value in the tree and create one out of Just values. The Maybe is evaluated to WHNF.

3. mapMaybeWithKey :: (Build1 -> a -> Maybe b) -> Radix1Tree a -> Radix1Tree b

   radix-tree	Data.Radix1Tree.Word8.Strict

   Apply a function to every value in the tree and create one out of Just values. The Maybe is evaluated to WHNF.

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

   radix-tree	Data.RadixTree.Word8.Lazy

   Apply a function to every value in the tree and create one out of Just values.

5. mapMaybeWithKey :: (Build -> a -> Maybe b) -> RadixTree a -> RadixTree b

   radix-tree	Data.RadixTree.Word8.Lazy

   Apply a function to every value in the tree and create one out of Just values.

6. mapMaybe :: (a -> Maybe b) -> RadixTree a -> RadixTree b

   radix-tree	Data.RadixTree.Word8.Strict

   Apply a function to every value in the tree and create one out of Just values. The Maybe is evaluated to WHNF.

7. mapMaybeWithKey :: (Build -> a -> Maybe b) -> RadixTree a -> RadixTree b

   radix-tree	Data.RadixTree.Word8.Strict

   Apply a function to every value in the tree and create one out of Just values. The Maybe is evaluated to WHNF.

8. unfoldlMRangeMaybe :: forall (w :: Natural) (v :: Nat) m a . (0 <= w, Unfoldl 0 v w, Monad m) => m Bool -> m a -> m (Maybe (RangeR v w a))

   ranged-list	Data.List.Range

   It is like unfoldlRangeMaybe. But it use a monad instead of a function. The first argument monad returns a boolean value. It creates values while this boolean value is True. If this boolean value is False before to create enough values or True after to create full values, then unfoldlMRangeMaybe returns Nothing.

   >>> :set -XDataKinds
   
   >>> :module + Data.IORef
   
   >>> r <- newIORef 1
   
   >>> check n0 = (< n0) <$> readIORef r
   
   >>> count = readIORef r >>= \n -> n * 3 <$ writeIORef r (n + 1)
   
   >>> unfoldlMRangeMaybe (check 2) count :: IO (Maybe (RangeR 3 5 Integer))
   Nothing
   

   >>> writeIORef r 1
   
   >>> unfoldlMRangeMaybe (check 5) count :: IO (Maybe (RangeR 3 5 Integer))
   Just ((((NilR :++ 12) :+ 9) :+ 6) :+ 3)
   

   >>> writeIORef r 1
   
   >>> unfoldlMRangeMaybe (check 10) count :: IO (Maybe (RangeR 3 5 Integer))
   Nothing
   

9. unfoldlMRangeMaybeWithBase :: (Unfoldl n v w, Monad m) => m Bool -> m a -> RangeR n w a -> m (Maybe (RangeR v w a))

   ranged-list	Data.List.Range

   It is like unfoldrMRangeMaybe. But it has already prepared values.

   >>> :set -XDataKinds
   
   >>> :module + Data.IORef
   
   >>> r <- newIORef 1
   
   >>> check = (< 3) <$> readIORef r
   
   >>> count = readIORef r >>= \n -> n * 3 <$ writeIORef r (n + 1)
   
   >>> xs = NilR :++ 123 :+ 456 :: RangeR 1 5 Integer
   
   >>> :{
   unfoldlMRangeMaybeWithBase check count xs
   :: IO (Maybe (RangeR 3 5 Integer))
   :}
   Just ((((NilR :++ 6) :+ 3) :+ 123) :+ 456)
   

10. unfoldlRangeMaybe :: forall (w :: Natural) (v :: Nat) s a . (0 <= w, Unfoldl 0 v w) => (s -> Maybe (s, a)) -> s -> Maybe (RangeR v w a)

    ranged-list	Data.List.Range

    To evaluate a function to construct a list. The function recieves a state and return a nothing value or an element and a new state. If the number of created elements is less than a minimum number of list elements or greater than a maximum number, then return Nothing.

    >>> :set -XDataKinds
    
    >>> count n0 n = if n < n0 then Just (n + 1, n * 3) else Nothing
    
    >>> unfoldlRangeMaybe (count 2) 1 :: Maybe (RangeR 3 5 Int)
    Nothing
    

    >>> unfoldlRangeMaybe (count 5) 1 :: Maybe (RangeR 3 5 Int)
    Just ((((NilR :++ 12) :+ 9) :+ 6) :+ 3)
    

    >>> unfoldlRangeMaybe (count 10) 1 :: Maybe (RangeR 3 5 Int)
    Nothing
    

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