Initial data commit

Task/Queue-Usage/Standard-ML/queue-usage-2.ml

@@ -0,0 +1,55 @@
+- open Queue;
+opening Queue
+  type 'a queue
+  exception Dequeue
+  val mkQueue : unit -> 'a queue
+  val clear : 'a queue -> unit
+  val isEmpty : 'a queue -> bool
+  val enqueue : 'a queue * 'a -> unit
+  val dequeue : 'a queue -> 'a
+  val next : 'a queue -> 'a option
+  val delete : 'a queue * ('a -> bool) -> unit
+  val head : 'a queue -> 'a
+  val peek : 'a queue -> 'a option
+  val length : 'a queue -> int
+  val contents : 'a queue -> 'a list
+  val app : ('a -> unit) -> 'a queue -> unit
+  val map : ('a -> 'b) -> 'a queue -> 'b queue
+  val foldl : ('a * 'b -> 'b) -> 'b -> 'a queue -> 'b
+  val foldr : ('a * 'b -> 'b) -> 'b -> 'a queue -> 'b
+- val q : int queue = mkQueue ();
+val q = - : int queue
+- isEmpty q;
+val it = true : bool
+- enqueue (q, 1);
+val it = () : unit
+- isEmpty q;
+val it = false : bool
+- enqueue (q, 2);
+val it = () : unit
+- enqueue (q, 3);
+val it = () : unit
+- peek q;
+val it = SOME 1 : int option
+- length q;
+val it = 3 : int
+- contents q;
+val it = [1,2,3] : int list
+- dequeue q;
+val it = 1 : int
+- dequeue q;
+val it = 2 : int
+- peek q;
+val it = SOME 3 : int option
+- length q;
+val it = 1 : int
+- enqueue (q, 4);
+val it = () : unit
+- dequeue q;
+val it = 3 : int
+- peek q;
+val it = SOME 4 : int option
+- dequeue q;
+val it = 4 : int
+- isEmpty q;
+val it = true : bool