*** empty log message ***

1 files changed, 40 insertions, 0 deletions

diff --git a/sources/scala/collection/mutable/ObservableMap.scala b/sources/scala/collection/mutable/ObservableMap.scala
new file mode 100644
index 0000000000..420a0feeaa
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+++ b/sources/scala/collection/mutable/ObservableMap.scala
@@ -0,0 +1,40 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003, LAMP/EPFL                  **
+**  __\ \/ /__/ __ |/ /__/ __ |                                         **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+** $Id$
+\*                                                                      */
+
+package scala;
+
+
+abstract class ObservableMap[A, B, This <: ObservableMap[A, B, This]]: This
+                    extends MutableMap[A, B]
+                    with Publisher[ObservableUpdate[Pair[A, B]] with Undo, This] {
+
+    override def update(key: A, value: B): Unit = get(key) match {
+        case None => super.update(key, value);
+                     publish(new Inclusion(Pair(key, value)) with Undo {
+                                 def undo = remove(key);
+                             });
+        case Some(old) => super.update(key, value);
+                          publish(new Modification(Pair(key, old), Pair(key, value)) with Undo {
+                                      def undo = update(key, old._2);
+                                  });
+    }
+
+    override def remove(key: A): Unit = get(key) match {
+        case None =>
+        case Some(old) => super.remove(key);
+                          publish(new Removal(Pair(key, old)) with Undo {
+                                      def undo = update(key, old);
+                                  });
+    }
+
+    override def clear: Unit = {
+        super.clear;
+        publish(new Reset() with Undo { def undo = error("cannot undo"); });
+    }
+}