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diff --git a/src/library/scalax/collection/generic/MapView.scala b/src/library/scalax/collection/generic/MapView.scala
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+++ b/src/library/scalax/collection/generic/MapView.scala
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+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2009, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+// $Id: Iterable.scala 15188 2008-05-24 15:01:02Z stepancheg $
+
+package scalax.collection.generic
+
+/** A non-strict view of a map.
+ * @author Martin Odersky
+ * @version 2.8
+ */
+trait MapView[+UC[A1, B1] <: MapTemplate[A1, B1, UC] with Map[A1, B1], A, B] extends Map[A, B] { self =>
+
+  val origin: Map[A, _]
+
+  def empty[C] = origin.empty[C]
+
+  def elements: Iterator[(A, B)]
+
+  val underlying: Map[A, _] = origin match {
+    case v: MapView[t, _, _] => v.underlying
+    case _ => origin
+  }
+  private[this] var forced: UC[A, B] = _
+  private[this] var wasForced = false
+
+  def force: UC[A, B] = {
+    if (!wasForced) {
+      forced = underlying.empty[B].asInstanceOf[UC[A, B]] ++ elements
+      wasForced = true
+    }
+    forced
+  }
+
+  def update (key: A, value: B): UC[A, B] = force update (key, value)
+  def - (key: A): UC[A, B] = force - key
+}
+
+