--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/anagram/support/agnotify.h	Sat Dec 22 17:52:45 2007 -0500
@@ -0,0 +1,74 @@
+/*
+ * AnaGram, A System for Syntax Directed Programming
+ * Copyright 1997-2002 Parsifal Software. All Rights Reserved.
+ * See the file COPYING for license and usage terms.
+ *
+ * agnotify.h
+ */
+
+#ifndef AGNOTIFY_H
+#define AGNOTIFY_H
+
+#include "agstack.h"
+
+
+class AgNotifierBase;
+
+class AgNotificationActionBase {
+protected:
+  AgStack<AgNotifierBase *> notifierStack;
+public:
+  AgNotificationActionBase() {}
+  virtual ~AgNotificationActionBase();
+  virtual void perform() {}
+  AgNotificationActionBase &attach(AgNotifierBase *notifier);
+  void remove(AgNotifierBase *notifier);
+};
+
+template <class T>
+class AgNotificationAction : public AgNotificationActionBase {
+protected:
+  T *object;
+  void (T::*memberFunction)();
+public:
+  AgNotificationAction(T *x, void (T::*f)()): object(x), memberFunction(f) {}
+  void perform() { (object->*memberFunction)(); }
+};
+
+class AgNotifierBase {
+protected:
+  AgStack<AgNotificationActionBase *> notifyStack;
+  void notify();
+
+public:
+  AgNotifierBase() {}
+  virtual ~AgNotifierBase();
+  void attach(AgNotificationActionBase *action) {
+    notifyStack.push(action);
+  }
+  void remove(AgNotificationActionBase *action);
+};
+
+template <class T>
+class AgNotifier : public AgNotifierBase {
+protected:
+  T contents;
+
+public:
+  AgNotifier(const T &d) : contents(d) {}
+  AgNotifier(const AgNotifier<T> &d) : contents(d.contents) {}
+  operator T &() { return contents; }
+  //T &data() { return contents; }
+  T *pointer() { return &contents; }
+  virtual void initialize(const T &d) {
+    contents = d;
+  }
+  virtual T &operator = (const T &d) {
+    contents = d;
+    notify();
+    return contents;
+  }
+};
+
+
+#endif /* AGNOTIFY_H */