containers- Assorted concrete container types

Copyright(c) David Feuer 2016
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An extremely light-weight, fast, and limited representation of a string of up to (2*WORDSIZE - 2) bits. In fact, there are two representations, misleadingly named bit queue builder and bit queue. The builder supports only emptyQB, creating an empty builder, and snocQB, enqueueing a bit. The bit queue builder is then turned into a bit queue using buildQ, after which bits can be removed one by one using unconsQ. If the size limit is exceeded, further operations will silently produce nonsense.



emptyQB :: BitQueueB Source #

Create an empty bit queue builder. This is represented as a single guard bit in the most significant position.

snocQB :: BitQueueB -> Bool -> BitQueueB Source #

Enqueue a bit. This works by shifting the queue right one bit, then setting the most significant bit as requested.

buildQ :: BitQueueB -> BitQueue Source #

Convert a bit queue builder to a bit queue. This shifts in a new guard bit on the left, and shifts right until the old guard bit falls off.

unconsQ :: BitQueue -> Maybe (Bool, BitQueue) Source #

Dequeue an element, or discover the queue is empty.

toListQ :: BitQueue -> [Bool] Source #

Convert a bit queue to a list of bits by unconsing. This is used to test that the queue functions properly.