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1. unfoldlRangeMaybeWithBase :: forall (n :: Nat) (v :: Nat) (w :: Nat) s a . Unfoldl n v w => (s -> Maybe (s, a)) -> s -> RangeR n w a -> Maybe (RangeR v w a)

   ranged-list	Data.List.Range

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

   >>> :set -XDataKinds
   
   >>> count n = if n < 3 then Just (n + 1, n * 3) else Nothing
   
   >>> xs = NilR :++ 123 :+ 456 :: RangeR 1 5 Int
   
   >>> unfoldlRangeMaybeWithBase count 1 xs :: Maybe (RangeR 3 5 Int)
   Just ((((NilR :++ 6) :+ 3) :+ 123) :+ 456)
   

2. unfoldrMRangeMaybe :: forall (w :: Natural) (v :: Nat) m a . (0 <= w, Unfoldr 0 v w, Monad m) => m Bool -> m a -> m (Maybe (RangeL v w a))

   ranged-list	Data.List.Range

   It is like unfoldrRangeMaybe. But it use a monad instead of a function. The first argument monad return boolean value. It create 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 unfoldrMRangeMaybe return Nothing.

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

   >>> writeIORef r 1
   
   >>> unfoldrMRangeMaybe (check 5) count :: IO (Maybe (RangeL 3 5 Integer))
   Just (3 :. (6 :. (9 :. (12 :.. NilL))))
   

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

3. unfoldrMRangeMaybeWithBase :: (Unfoldr n v w, Monad m) => RangeL n w a -> m Bool -> m a -> m (Maybe (RangeL v w a))

   ranged-list	Data.List.Range

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

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

4. unfoldrRangeMaybe :: forall (w :: Natural) (v :: Nat) s a . (0 <= w, Unfoldr 0 v w) => (s -> Maybe (a, s)) -> s -> Maybe (RangeL v w a)

   ranged-list	Data.List.Range

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

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

   >>> unfoldrRangeMaybe (next 5) 1 :: Maybe (RangeL 3 5 Int)
   Just (3 :. (6 :. (9 :. (12 :.. NilL))))
   

   >>> unfoldrRangeMaybe (next 10) 1 :: Maybe (RangeL 3 5 Int)
   Nothing
   

5. unfoldrRangeMaybeWithBase :: forall (n :: Nat) (v :: Nat) (w :: Nat) a s . Unfoldr n v w => RangeL n w a -> (s -> Maybe (a, s)) -> s -> Maybe (RangeL v w a)

   ranged-list	Data.List.Range

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

   >>> :set -XDataKinds
   
   >>> xs = 123 :. 456 :.. NilL :: RangeL 1 5 Int
   
   >>> next n = if n < 3 then Just (n * 3, n + 1) else Nothing
   
   >>> unfoldrRangeMaybeWithBase xs next 1 :: Maybe (RangeL 3 5 Int)
   Just (123 :. (456 :. (3 :. (6 :.. NilL))))
   

6. fromMaybe :: Exception e => e -> Maybe a -> BitGet a

   rattletrap	Rattletrap.Type.Attribute

   No documentation available.

7. whenMaybe :: Applicative m => Bool -> m a -> m (Maybe a)

   rattletrap	Rattletrap.Utility.Monad

   No documentation available.

8. indexMaybe :: ByteString -> Int -> Maybe Word8

   rawfilepath	Data.ByteString.RawFilePath

   O(1) ByteString index, starting from 0, that returns Just if:

   0 <= n < length bs
   

9. decodeMaybeOf :: Typeable a => Typed (Decoder a -> Decoder (Maybe a))

   registry-aeson	Data.Registry.Aeson.Decoder

   Add a Maybe (Decoder a) to a registry of decoders usage: decoders = decodeMaybeOf @a <: otherDecoders the list of otherDecoders must contain a Decoder a otherwise there will be a compilation error

10. encodeMaybeOf :: Typeable a => Typed (Encoder a -> Encoder (Maybe a))

    registry-aeson	Data.Registry.Aeson.Encoder

    Create an Encoder for a (Maybe a)

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