*** empty log message ***

1 files changed, 46 insertions, 0 deletions

diff --git a/sources/scala/collection/mutable/DefaultMapModel.scala b/sources/scala/collection/mutable/DefaultMapModel.scala
new file mode 100644
index 0000000000..2e272dc59b
--- /dev/null
+++ b/sources/scala/collection/mutable/DefaultMapModel.scala
@@ -0,0 +1,46 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003, LAMP/EPFL                  **
+**  __\ \/ /__/ __ |/ /__/ __ |                                         **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+// $Id$
+
+
+package scala;
+
+
+trait DefaultMapModel[A, B] extends MutableMap[A, B] {
+
+	protected def findEntry(key: A): Option[Entry];
+
+	protected def addEntry(e: Entry): Unit;
+
+    protected def entries: Iterator[Entry];
+
+    def get(key: A) = findEntry(key) match {
+        case None => None
+        case Some(e) => Some(e.value);
+    }
+
+    def update(key: A, value: B) = findEntry(key) match {
+        case None => addEntry(new Entry(key, value));
+        case Some(e) => e.value = value;
+    }
+
+    def elements = new Iterator[Pair[A, B]] {
+        val iter = entries;
+        def hasNext = iter.hasNext;
+        def next = iter.next.toPair;
+    }
+
+    protected class Entry(k: A, v: B) {
+        def key = k;
+        var value = v;
+        def toPair = Pair(k, value);
+        override def toString() = k.toString() + " -> " + value;
+    }
+
+}