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(lispkit queue)
Library
(lispkit queue)
provides an implementation for mutable queues, i.e. mutable FIFO buffers.queue-type-tag

Symbol representing the
queue
type. The type-for
procedure of library (lispkit type)
returns this symbol for all queue objects.(make-queue)

Returns a new empty queue.
(queue x ...)

Returns a new queue with x on its first position followed by the remaining parameters.
(dequeue! (queue 1 2 3)) ⇒ 1
(queue? obj)

Returns
#t
if obj is a queue; otherwise #f
is returned.(queue-empty? q)

Returns
#t
if queue q is empty.(queue-size q)

Returns the size of queue q, i.e. the number of elements buffered in q.
(queue=? q1 q2)

Returns
#t
if queue q1 has the exact same elements in the same order like queue q2; otherwise, #f
is returned.(enqueue! q x)

Inserts element x at the end of queue q.
(queue-front q)

Returns the first element in queue q. If the queue is empty, an error is raised.
(dequeue! q)

Removes the first element from queue q and returns its value.
(define q (make-queue))
(enqueue! q 1)
(enqueue! q 2)
(dequeue! q) ⇒ 1
(queue-front q) ⇒ 2
(queue-size q) ⇒ 1
(queue-clear! q)

Removes all elements from queue q.
(queue-copy q)

Returns a copy of queue q.
(queue->list q)

Returns a list consisting of all elements in queue q in the order they were inserted, i.e. starting with the first element.
(define q (make-queue))
(enqueue! q 1)
(enqueue! q 2)
(enqueue! q 3)
(queue->list q) ⇒ (1 2 3)
(list->queue l)

Returns a new queue consisting of the elements of list l. The first element in l will become the front element of the new queue that is returned.
(dequeue! (list->queue '(1 2 3))) ⇒ 1
(list->queue! s l)

Inserts the elements of list l into queue q in the order they appear in the list.
(define q (list->queue '(1 2 3)))
(list->queue! q '(4 5 6))
(queue->list q) ⇒ (1 2 3 4 5 6)
Last modified 1yr ago