Data.Enumerator.List

This module is intended to be imported qualified:

 import qualified Data.Enumerator.List as EL

Since: 0.4.5

List analogues

Folds

fold :: Monad m => (b -> a -> b) -> b -> Iteratee a m b

Consume the entire input stream with a strict left fold, one element at a time.

Since: 0.4.8

foldM :: Monad m => (b -> a -> m b) -> b -> Iteratee a m b

Consume the entire input stream with a strict monadic left fold, one element at a time.

Since: 0.4.8

Maps

map :: Monad m => (ao -> ai) -> Enumeratee ao ai m b

map f applies f to each input element and feeds the resulting outputs to the inner iteratee.

Since: 0.4.8

mapM :: Monad m => (ao -> m ai) -> Enumeratee ao ai m b

mapM f applies f to each input element and feeds the resulting outputs to the inner iteratee.

Since: 0.4.8

mapM_ :: Monad m => (a -> m b) -> Iteratee a m ()

mapM_ f applies f to each input element, and discards the results.

Since: 0.4.11

concatMap :: Monad m => (ao -> [ai]) -> Enumeratee ao ai m b

concatMap f applies f to each input element and feeds the resulting outputs to the inner iteratee.

Since: 0.4.8

concatMapM :: Monad m => (ao -> m [ai]) -> Enumeratee ao ai m b

concatMapM f applies f to each input element and feeds the resulting outputs to the inner iteratee.

Since: 0.4.8

Accumulating maps

mapAccum :: Monad m => (s -> ao -> (s, ai)) -> s -> Enumeratee ao ai m b

Similar to map, but with a stateful step function.

Since: 0.4.9

mapAccumM :: Monad m => (s -> ao -> m (s, ai)) -> s -> Enumeratee ao ai m b

Similar to mapM, but with a stateful step function.

Since: 0.4.9

concatMapAccum :: Monad m => (s -> ao -> (s, [ai])) -> s -> Enumeratee ao ai m b

Similar to concatMap, but with a stateful step function.

Since: 0.4.11

concatMapAccumM :: Monad m => (s -> ao -> m (s, [ai])) -> s -> Enumeratee ao ai m b

Similar to concatMapM, but with a stateful step function.

Since: 0.4.11

Infinite streams

iterate :: Monad m => (a -> a) -> a -> Enumerator a m b

iterate f x enumerates an infinite stream of repeated applications of f to x.

Analogous to iterate.

Since: 0.4.8

iterateM :: Monad m => (a -> m a) -> a -> Enumerator a m b

Similar to iterate, except the iteration function is monadic.

Since: 0.4.8

repeat :: Monad m => a -> Enumerator a m b

Enumerates an infinite stream of a single element.

Analogous to repeat.

Since: 0.4.8

repeatM :: Monad m => m a -> Enumerator a m b

Enumerates an infinite stream of element. Each element is computed by the underlying monad.

Since: 0.4.8

Bounded streams

replicate :: Monad m => Integer -> a -> Enumerator a m b

replicate n x enumerates a stream containing n copies of x.

Analogous to replicate.

Since: 0.4.8

replicateM :: Monad m => Integer -> m a -> Enumerator a m b

replicateM n m_x enumerates a stream of n elements, with each element computed by m_x.

Since: 0.4.8

generateM :: Monad m => m (Maybe a) -> Enumerator a m b

Like repeatM, except the computation may terminate the stream by returning Nothing.

Since: 0.4.8

unfold :: Monad m => (s -> Maybe (a, s)) -> s -> Enumerator a m b

Enumerates a stream of elements by repeatedly applying a function to some state.

Similar to iterate.

Since: 0.4.8

unfoldM :: Monad m => (s -> m (Maybe (a, s))) -> s -> Enumerator a m b

Enumerates a stream of elements by repeatedly applying a computation to some state.

Similar to iterateM.

Since: 0.4.8

Dropping input

drop :: Monad m => Integer -> Iteratee a m ()

drop n ignores n input elements from the stream.

Since: 0.4.5

dropWhile :: Monad m => (a -> Bool) -> Iteratee a m ()

dropWhile p ignores input from the stream until the first element which does not match the predicate.

Since: 0.4.5

filter :: Monad m => (a -> Bool) -> Enumeratee a a m b

Applies a predicate to the stream. The inner iteratee only receives elements for which the predicate is True.

Since: 0.4.8

filterM :: Monad m => (a -> m Bool) -> Enumeratee a a m b

Applies a monadic predicate to the stream. The inner iteratee only receives elements for which the predicate returns True.

Since: 0.4.8

unique :: (Ord a, Monad m) => Enumeratee a a m b

Remove duplicate elements from a stream, passing through the first instance of each value.

Similar to nub, but more efficient because it uses a Set internally.

Since: 0.4.11

Consumers

head :: Monad m => Iteratee a m (Maybe a)

Get the next element from the stream, or Nothing if the stream has ended.

Since: 0.4.5

head_ :: Monad m => Iteratee a m a

Get the next element from the stream, or raise an error if the stream has ended.

Since: 0.4.14

take :: Monad m => Integer -> Iteratee a m [a]

take n extracts the next n elements from the stream, as a list.

Since: 0.4.5

takeWhile :: Monad m => (a -> Bool) -> Iteratee a m [a]

takeWhile p extracts input from the stream until the first element which does not match the predicate.

Since: 0.4.5

consume :: Monad m => Iteratee a m [a]

consume = takeWhile (const True)

Since: 0.4.5

Zipping

zip :: Monad m => Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m (b1, b2)

Pass input from a stream through two iteratees at once. Excess input is yielded if it was not consumed by either iteratee.

Analogous to zip.

Since: 0.4.14

zip3 :: Monad m => Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m (b1, b2, b3)

Pass input from a stream through three iteratees at once. Excess input is yielded if it was not consumed by any iteratee.

Analogous to zip3.

Since: 0.4.14

zip4 :: Monad m => Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m (b1, b2, b3, b4)

Pass input from a stream through four iteratees at once. Excess input is yielded if it was not consumed by any iteratee.

Analogous to zip4.

Since: 0.4.14

zip5 :: Monad m => Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m b5 -> Iteratee a m (b1, b2, b3, b4, b5)

Pass input from a stream through five iteratees at once. Excess input is yielded if it was not consumed by any iteratee.

Analogous to zip5.

Since: 0.4.14

zip6 :: Monad m => Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m b5 -> Iteratee a m b6 -> Iteratee a m (b1, b2, b3, b4, b5, b6)

Pass input from a stream through six iteratees at once. Excess input is yielded if it was not consumed by any iteratee.

Analogous to zip6.

Since: 0.4.14

zip7 :: Monad m => Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m b5 -> Iteratee a m b6 -> Iteratee a m b7 -> Iteratee a m (b1, b2, b3, b4, b5, b6, b7)

Pass input from a stream through seven iteratees at once. Excess input is yielded if it was not consumed by any iteratee.

Analogous to zip7.

Since: 0.4.14

zipWith :: Monad m => (b1 -> b2 -> c) -> Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m c

Pass input from a stream through two iteratees at once. Excess input is yielded if it was not consumed by either iteratee. Output from the iteratees is combined with a user-provided function.

Analogous to zipWith.

Since: 0.4.14

zipWith3 :: Monad m => (b1 -> b2 -> b3 -> c) -> Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m c

Pass input from a stream through two iteratees at once. Excess input is yielded if it was not consumed by either iteratee. Output from the iteratees is combined with a user-provided function.

Analogous to zipWith3.

Since: 0.4.14

zipWith4 :: Monad m => (b1 -> b2 -> b3 -> b4 -> c) -> Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m c

Pass input from a stream through two iteratees at once. Excess input is yielded if it was not consumed by either iteratee. Output from the iteratees is combined with a user-provided function.

Analogous to zipWith4.

Since: 0.4.14

zipWith5 :: Monad m => (b1 -> b2 -> b3 -> b4 -> b5 -> c) -> Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m b5 -> Iteratee a m c

Pass input from a stream through two iteratees at once. Excess input is yielded if it was not consumed by either iteratee. Output from the iteratees is combined with a user-provided function.

Analogous to zipWith5.

Since: 0.4.14

zipWith6 :: Monad m => (b1 -> b2 -> b3 -> b4 -> b5 -> b6 -> c) -> Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m b5 -> Iteratee a m b6 -> Iteratee a m c

Pass input from a stream through two iteratees at once. Excess input is yielded if it was not consumed by either iteratee. Output from the iteratees is combined with a user-provided function.

Analogous to zipWith6.

Since: 0.4.14

zipWith7 :: Monad m => (b1 -> b2 -> b3 -> b4 -> b5 -> b6 -> b7 -> c) -> Iteratee a m b1 -> Iteratee a m b2 -> Iteratee a m b3 -> Iteratee a m b4 -> Iteratee a m b5 -> Iteratee a m b6 -> Iteratee a m b7 -> Iteratee a m c

Pass input from a stream through two iteratees at once. Excess input is yielded if it was not consumed by either iteratee. Output from the iteratees is combined with a user-provided function.

Analogous to zipWith7.

Since: 0.4.14

Unsorted

require :: Monad m => Integer -> Iteratee a m ()

require n buffers input until at least n elements are available, or throws an error if the stream ends early.

Since: 0.4.5

isolate :: Monad m => Integer -> Enumeratee a a m b

isolate n reads at most n elements from the stream, and passes them to its iteratee. If the iteratee finishes early, elements continue to be consumed from the outer stream until n have been consumed.

Since: 0.4.5

isolateWhile :: Monad m => (a -> Bool) -> Enumeratee a a m b

isolateWhile p reads elements from the stream until p is false, and passes them to its iteratee. If the iteratee finishes early, elements continue to be consumed from the outer stream until p is false.

Since: 0.4.16

splitWhen :: Monad m => (a -> Bool) -> Enumeratee a [a] m b

Split on elements satisfying a given predicate.

Since: 0.4.8