foldr package:containers

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

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

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

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

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.

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)"

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.

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.

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.

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)"

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.

foldrWithIndex is a version of foldr that also provides access to the index of each element.

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.

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.