tasks a-s

Task/Priority-queue/Standard-ML/priority-queue.ml

@@ -0,0 +1,29 @@
+structure TaskPriority = struct
+  type priority = int
+  val compare = Int.compare
+  type item = int * string
+  val priority : item -> int = #1
+end
+
+structure PQ = LeftPriorityQFn (TaskPriority)
+;
+
+let
+  val tasks = [
+    (3, "Clear drains"),
+    (4, "Feed cat"),
+    (5, "Make tea"),
+    (1, "Solve RC tasks"),
+    (2, "Tax return")]
+  val pq = foldr PQ.insert PQ.empty tasks
+  (* or val pq = PQ.fromList tasks *)
+  fun aux pq' =
+    case PQ.next pq' of
+      NONE => ()
+    | SOME ((prio, name), pq'') => (
+        print (Int.toString prio ^ ", " ^ name ^ "\n");
+        aux pq''
+      )
+in
+  aux pq
+end