queue.tem

(page "Queue operations"
(import "docs/queue0.html")
(newtable "Queue operations"
(def queue "" "Creates a queue." (tests (queue) (type (queue))))
(def destructive enq "obj q" "Adds obj to the end of queue q.  Returns the queue as a list. The operation is wrapped in <code>atomic</code>."
(tests (let q (queue) (enq 'a q) (enq '(1 2) q))))
(def destructive enq-limit "obj q [limit]" "Adds obj to the queue q.  If the new length would exceed the limit, the first element is dequeued.  The new contents of the queue is returned as a list.  Note that the length of the queue will either grow by one or remain constant; the queue will not be shortened to the limit.  The operation is wrapped in <code>atomic</code>."
(tests "(let q (queue)
  (enq-limit 'a q 2)
  (enq-limit 'b q 2)
  (enq-limit 'c q 2))"))
(def destructive deq "q" "Removes the first element from the queue q and returns the removed element.  The operation is wrapped in <code>atomic</code>."
(tests (let q (queue) (enq 'a q) (enq 4 q) (deq q))))
(def qlen "q" "Returns the length of queue q."
(tests (let q (queue) (enq 'a q) (enq 4 q) (deq q) (qlen q))))
(def qlist "q" "Returns the contents of queue q as a list."
(tests (let q (queue) (enq 'a q) (enq '(1 2) q) (qlist q))))
)
)