package batteries

The type of queues containing elements of type 'a.

Raised when Queue.take or Queue.peek is applied to an empty queue.

Return a new queue, initially empty.

add x q adds the element x at the end of the queue q.

push is a synonym for add.

pop is a synonym for take.

top is a synonym for peek.

Discard all elements from a queue.

Return a copy of the given queue.

Return true if the given queue is empty, false otherwise.

Return the number of elements in a queue.

iter f q applies f in turn to all elements of q, from the least recently entered to the most recently entered. The queue itself is unchanged.

map f q applies function f to each element of the queue and returns a new queue q' with the results returned by f. Order is preserved and q is not consumed. So that if take q returns x take q' will return f x.

• since 2.3.0

filter p q returns a new queue that contain the elements of q that satisfy the predicate p, in the same order.

• since 2.4

filter_map f q applies f to the elements a0,a1..an of q in order, and returns the queue of the elements bi such that f ai = Some bi, in the corresponding order.

• since 2.4

filter_inplace p q removes all the elements of the queue q that don't satisfy the predicate p. The order of the elements in the queue is preserved.

• since 2.4

fold f accu q is equivalent to List.fold_left f accu l, where l is the list of q's elements. The queue remains unchanged.

transfer q1 q2 adds all of q1's elements at the end of the queue q2, then clears q1. It is equivalent to the sequence iter (fun x -> add x q2) q1; clear q1, but runs in constant time.

enum q returns a destructive enumeration of the elements of queue q, from the least recently entered to the most recently entered. Reading the enumeration will progressively empty q.

of_enum e returns a new queue containing all the elements of e. This is equivalent to calling push with the first element of the enumeration, then with the second, etc.