**foldr** -base

foldr, applied to a binary operator, a starting value (typically the right-identity of the operator), and a packed string, reduces the packed string using the binary operator, from right to left.
*O(n)* foldr, applied to a binary operator, a starting value (typically the right-identity of the operator), and a Text, reduces the Text using the binary operator, from right to left. Subject to fusion.
*O(n)*. Fold the elements in the set using the given right-associative binary operator, such that foldr f z == foldr f z . toAscList.
For example,
> toAscList set = foldr (:) [] set
foldr, applied to a binary operator, a starting value (typically the right-identity of the operator), and a ByteString, reduces the ByteString using the binary operator, from right to left.
*O(n)*. Fold the values in the map using the given right-associative binary operator, such that foldr f z == foldr f z . elems.
For example,
> elems map = foldr (:) [] map
> let f a len = len + (length a)
> foldr f 0 (fromList [(5,"a"), (3,"bbb")]) == 4
*O(n)*. Fold the values in the map using the given right-associative binary operator, such that foldr f z == foldr f z . elems.
For example,
> elems map = foldr (:) [] map
> let f a len = len + (length a)
> foldr f 0 (fromList [(5,"a"), (3,"bbb")]) == 4
*O(n)*. Fold the elements in the set using the given right-associative binary operator, such that foldr f z == foldr f z . toAscList.
For example,
> toAscList set = foldr (:) [] set
'foldr\'' is a strict variant of foldr

*O(n)*. A strict version of foldr. Each application of the operator is evaluated before using the result in the next application. This function is strict in the starting value.
'foldr\'' is like foldr, but strict in the accumulator.
*O(n)*. A strict version of foldr. Each application of the operator is evaluated before using the result in the next application. This function is strict in the starting value.
*O(n)*. A strict version of foldr. Each application of the operator is evaluated before using the result in the next application. This function is strict in the starting value.
*O(n)*. A strict version of foldr. Each application of the operator is evaluated before using the result in the next application. This function is strict in the starting value.
foldr1 is a variant of foldr that has no starting value argument, and thus must be applied to non-empty ByteStrings
*O(n)* A variant of foldr that has no starting value argument, and thus must be applied to a non-empty Text. Subject to fusion.
foldr1 is a variant of foldr that has no starting value argument, and thus must be applied to non-empty ByteStrings
foldr1 is a variant of foldr that has no starting value argument, and thus must be applied to non-empty ByteStrings An exception will be thrown in the case of an empty ByteString.
A strict variant of foldr1

'foldr1\'' is a variant of foldr1, but is strict in the accumulator.
Consume the chunks of a lazy ByteString with a natural right fold.

Consume the chunks of a lazy Text with a natural right fold.
*O(n)*. Fold the keys and values in the map using the given right-associative binary operator, such that foldrWithKey f z == foldr (uncurry f) z . toAscList.
For example,
> keys map = foldrWithKey (\k x ks -> k:ks) [] map
> let f k a result = result ++ "(" ++ (show k) ++ ":" ++ a ++ ")"
> foldrWithKey f "Map: " (fromList [(5,"a"), (3,"b")]) == "Map: (5:a)(3:b)"
*O(n)*. Fold the keys and values in the map using the given right-associative binary operator, such that foldrWithKey f z == foldr (uncurry f) z . toAscList.
For example,
> keys map = foldrWithKey (\k x ks -> k:ks) [] map
> let f k a result = result ++ "(" ++ (show k) ++ ":" ++ a ++ ")"
> foldrWithKey f "Map: " (fromList [(5,"a"), (3,"b")]) == "Map: (5:a)(3:b)"
*O(n)*. A strict version of foldrWithKey. Each application of the operator is evaluated before using the result in the next application. This function is strict in the starting value.
*O(n)*. A strict version of foldrWithKey. Each application of the operator is evaluated before using the result in the next application. This function is strict in the starting value.
Create a Builder that encodes a sequence generated from a seed value using a BoundedPrim for each sequence element.
*O(n)* The unfoldr function is analogous to the List 'unfoldr'. unfoldr builds a ByteString from a seed value. The function takes the element and returns Nothing if it is done producing the ByteString or returns Just (a,b), in which case, a is a prepending to the ByteString and b is used as the next element in a recursive call.
*O(n)*, unfoldr function is analogous to the List 'unfoldr'. unfoldr builds a ByteString from a seed value. The function takes the element and returns Nothing if it is done producing the ByteString or returns Just (a,b), in which case, a is the next character in the string, and b is the seed value for further production.
Examples:
> unfoldr (\x -> if x <= '9' then Just (x, succ x) else Nothing) '0' == "0123456789"
*O(n)*, unfoldr function is analogous to the List unfoldr. unfoldr builds a Text from a seed value. The function takes the element and returns Nothing if it is done producing the Text, otherwise Just (a,b). In this case, a is the next Char in the string, and b is the seed value for further production. Performs replacement on invalid scalar values.
*O(n)*, unfoldr function is analogous to the List unfoldr. unfoldr builds a Text from a seed value. The function takes the element and returns Nothing if it is done producing the Text, otherwise Just (a,b). In this case, a is the next Char in the string, and b is the seed value for further production. Subject to fusion. Performs replacement on invalid scalar values.
*O(n)* The unfoldr function is analogous to the List 'unfoldr'. unfoldr builds a ByteString from a seed value. The function takes the element and returns Nothing if it is done producing the ByteString or returns Just (a,b), in which case, a is a prepending to the ByteString and b is used as the next element in a recursive call.
*O(n)*, unfoldr function is analogous to the List 'unfoldr'. unfoldr builds a ByteString from a seed value. The function takes the element and returns Nothing if it is done producing the ByteString or returns Just (a,b), in which case, a is the next byte in the string, and b is the seed value for further production.
Examples:
> unfoldr (\x -> if x <= 5 then Just (x, x + 1) else Nothing) 0
> == pack [0, 1, 2, 3, 4, 5]
Builds a sequence from a seed value. Takes time linear in the number of generated elements. *WARNING:* If the number of generated elements is infinite, this method will not terminate.

*O(n)* Like unfoldr, unfoldrN builds a ByteString from a seed value. However, the length of the result is limited by the first argument to unfoldrN. This function is more efficient than unfoldr when the maximum length of the result is known.
The following equation relates unfoldrN and unfoldr:
> unfoldrN n f s == take n (unfoldr f s)
*O(n)* Like unfoldr, unfoldrN builds a Text from a seed value. However, the length of the result should be limited by the first argument to unfoldrN. This function is more efficient than unfoldr when the maximum length of the result is known and correct, otherwise its performance is similar to unfoldr. Subject to fusion. Performs replacement on invalid scalar values.
*O(n)* Like unfoldr, unfoldrN builds a ByteString from a seed value. However, the length of the result is limited by the first argument to unfoldrN. This function is more efficient than unfoldr when the maximum length of the result is known.
The following equation relates unfoldrN and unfoldr:
> fst (unfoldrN n f s) == take n (unfoldr f s)
*O(n)* Like unfoldr, unfoldrN builds a Text from a seed value. However, the length of the result should be limited by the first argument to unfoldrN. This function is more efficient than unfoldr when the maximum length of the result is known and correct, otherwise its performance is similar to unfoldr. Performs replacement on invalid scalar values.