Let's have Set implement forEach, like Map does.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@5500 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/as/com/threerings/util/ExpiringSet.as

@@ -62,6 +62,14 @@ public class ExpiringSet extends EventDispatcher
         _data.length = 0;
     }
 
+    // from Set
+    public function forEach (fn :Function) :void
+    {
+        for each (var e :ExpiringElement in _data) {
+            fn(e);
+        }
+    }
+
     // from Set
     public function size () :int
     {

src/as/com/threerings/util/HashSet.as

@@ -76,6 +76,13 @@ public class HashSet
         return (_hashMap.containsKey(o));
     }
 
+    public function forEach (fn :Function) :void
+    {
+        _hashMap.forEach(function (key :Object, val :Object) :void {
+            fn(key);
+        });
+    }
+
     public function size () :int
     {
         return (_hashMap.size());

src/as/com/threerings/util/Set.as

@@ -41,6 +41,9 @@ public interface Set
     /** Returns true if this set contains the specified element. */
     function contains (o :Object) :Boolean;
 
+    /** Call the specified function, which accepts an element as an argument. */
+    function forEach (fn :Function) :void;
+
     /** Retuns the number of elements in this set. */
     function size () :int; // @TSC - should this be uint?