mapAccum

mapAccum :: (a -> b -> (a, c)) -> a -> IntMap b -> (a, IntMap c)
containers Data.IntMap.Strict, containers Data.IntMap.Lazy
O(n). The function mapAccum threads an accumulating argument through the map in ascending order of keys. > let f a b = (a ++ b, b ++ "X") > mapAccum f "Everything: " (fromList [(5,"a"), (3,"b")]) == ("Everything: ba", fromList [(3, "bX"), (5, "aX")])
mapAccum :: (a -> b -> (a, c)) -> a -> Map k b -> (a, Map k c)
containers Data.Map.Lazy, containers Data.Map.Strict
O(n). The function mapAccum threads an accumulating argument through the map in ascending order of keys. > let f a b = (a ++ b, b ++ "X") > mapAccum f "Everything: " (fromList [(5,"a"), (3,"b")]) == ("Everything: ba", fromList [(3, "bX"), (5, "aX")])
mapAccumL :: (acc -> x -> (acc, y)) -> acc -> [x] -> (acc, [y])
base Data.List
The mapAccumL function behaves like a combination of map and foldl; it applies a function to each element of a list, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new list.
mapAccumL :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c)
base Data.Traversable
The mapAccumL function behaves like a combination of fmap and foldl; it applies a function to each element of a structure, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new structure.
mapAccumR :: (acc -> x -> (acc, y)) -> acc -> [x] -> (acc, [y])
base Data.List
The mapAccumR function behaves like a combination of map and foldr; it applies a function to each element of a list, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new list.
mapAccumR :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c)
base Data.Traversable
The mapAccumR function behaves like a combination of fmap and foldr; it applies a function to each element of a structure, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new structure.
mapAccumL :: (a -> Char -> (a, Char)) -> a -> Text -> (a, Text)
text Data.Text, text Data.Text.Lazy
O(n) Like a combination of map and foldl'. Applies a function to each element of a Text, passing an accumulating parameter from left to right, and returns a final Text. Performs replacement on invalid scalar values.
mapAccumL :: (acc -> Char -> (acc, Char)) -> acc -> ByteString -> (acc, ByteString)
bytestring Data.ByteString.Lazy.Char8
The mapAccumL function behaves like a combination of map and foldl; it applies a function to each element of a ByteString, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new ByteString.
mapAccumL :: (acc -> Char -> (acc, Char)) -> acc -> ByteString -> (acc, ByteString)
bytestring Data.ByteString.Char8
The mapAccumL function behaves like a combination of map and foldl; it applies a function to each element of a ByteString, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new list.
mapAccumL :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString)
bytestring Data.ByteString.Lazy
The mapAccumL function behaves like a combination of map and foldl; it applies a function to each element of a ByteString, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new ByteString.
mapAccumL :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString)
bytestring Data.ByteString
The mapAccumL function behaves like a combination of map and foldl; it applies a function to each element of a ByteString, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new list.
mapAccumR :: (a -> Char -> (a, Char)) -> a -> Text -> (a, Text)
text Data.Text, text Data.Text.Lazy
The mapAccumR function behaves like a combination of map and a strict foldr; it applies a function to each element of a Text, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new Text. Performs replacement on invalid scalar values.
mapAccumR :: (acc -> Char -> (acc, Char)) -> acc -> ByteString -> (acc, ByteString)
bytestring Data.ByteString.Char8, bytestring Data.ByteString.Lazy.Char8
The mapAccumR function behaves like a combination of map and foldr; it applies a function to each element of a ByteString, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new ByteString.
mapAccumR :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString)
bytestring Data.ByteString, bytestring Data.ByteString.Lazy
The mapAccumR function behaves like a combination of map and foldr; it applies a function to each element of a ByteString, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new ByteString.
mapAccumRWithKey :: (a -> Key -> b -> (a, c)) -> a -> IntMap b -> (a, IntMap c)
containers Data.IntMap.Strict, containers Data.IntMap.Lazy
O(n). The function mapAccumR threads an accumulating argument through the map in descending order of keys.
mapAccumRWithKey :: (a -> k -> b -> (a, c)) -> a -> Map k b -> (a, Map k c)
containers Data.Map.Lazy, containers Data.Map.Strict
O(n). The function mapAccumR threads an accumulating argument through the map in descending order of keys.
mapAccumWithKey :: (a -> Key -> b -> (a, c)) -> a -> IntMap b -> (a, IntMap c)
containers Data.IntMap.Strict, containers Data.IntMap.Lazy
O(n). The function mapAccumWithKey threads an accumulating argument through the map in ascending order of keys. > let f a k b = (a ++ " " ++ (show k) ++ "-" ++ b, b ++ "X") > mapAccumWithKey f "Everything:" (fromList [(5,"a"), (3,"b")]) == ("Everything: 3-b 5-a", fromList [(3, "bX"), (5, "aX")])
mapAccumWithKey :: (a -> k -> b -> (a, c)) -> a -> Map k b -> (a, Map k c)
containers Data.Map.Lazy, containers Data.Map.Strict
O(n). The function mapAccumWithKey threads an accumulating argument through the map in ascending order of keys. > let f a k b = (a ++ " " ++ (show k) ++ "-" ++ b, b ++ "X") > mapAccumWithKey f "Everything:" (fromList [(5,"a"), (3,"b")]) == ("Everything: 3-b 5-a", fromList [(3, "bX"), (5, "aX")])
gmapAccumA :: (Data d, Applicative a) => (forall e. Data e => b -> e -> (b, a e)) -> b -> d -> (b, a d)
syb Data.Generics.Twins
Applicative version
gmapAccumM :: (Data d, Monad m) => (forall e. Data e => a -> e -> (a, m e)) -> a -> d -> (a, m d)
syb Data.Generics.Twins
gmapM with accumulation

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