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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
}
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