Data.Array.ST.Iterator

data Iterator h a

This type provides a slightly easier way of iterating over an array's elements in an STArray computation, without having to keep track of indices.

iterator :: forall r h a. (Int -> Maybe a) -> Eff (st :: ST h | r) (Iterator h a)

Make an Iterator given an indexing function into an array (or anything else). If xs :: Array a, the standard way to create an iterator over xs is to use iterator (xs !! _), where (!!) comes from Data.Array.

iterate :: forall r h a. Iterator h a -> (a -> Eff (st :: ST h | r) Unit) -> Eff (st :: ST h | r) Unit

Perform an action once for each item left in an iterator. If the action itself also advances the same iterator, iterate will miss those items out.

next :: forall r h a. Iterator h a -> Eff (st :: ST h | r) (Maybe a)

Get the next item out of an iterator, advancing it. Returns Nothing if the Iterator is exhausted.

peek :: forall r h a. Iterator h a -> Eff (st :: ST h | r) (Maybe a)

Get the next item out of an iterator without advancing it.

exhausted :: forall r h a. Iterator h a -> Eff (st :: ST h | r) Boolean

Check whether an iterator has been exhausted.

pushWhile :: forall r h a. (a -> Boolean) -> Iterator h a -> STArray h a -> Eff (st :: ST h | r) Unit

Extract elements from an iterator and push them on to an STArray for as long as those elements satisfy a given predicate.

pushAll :: forall r h a. Iterator h a -> STArray h a -> Eff (st :: ST h | r) Unit

Push the entire remaining contents of an iterator onto an STArray.