Scala example source code file (MapProxy.scala)

This example Scala source code file (MapProxy.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

a, b, b1, gentraversableonce, map, mapproxy, mapproxylike, proxying

The MapProxy.scala Scala example source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2003-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */

package scala
package collection
package mutable

/**
 *  This trait implements a proxy for [[scala.collection.mutable.Map]].
 *
 *  It is most useful for assembling customized map abstractions
 *  dynamically using object composition and forwarding.
 *
 *  @author  Matthias Zenger, Martin Odersky
 *  @version 2.0, 31/12/2006
 *  @since   1
 */
@deprecated("Proxying is deprecated due to lack of use and compiler-level support.", "2.11.0")
trait MapProxy[A, B] extends Map[A, B] with MapProxyLike[A, B, Map[A, B]] {
  private def newProxy[B1 >: B](newSelf: Map[A, B1]): MapProxy[A, B1] =
    new MapProxy[A, B1] { val self = newSelf }

  override def repr = this
  override def empty: MapProxy[A, B] = new MapProxy[A, B] { val self = MapProxy.this.self.empty }
  override def updated [B1 >: B](key: A, value: B1) = newProxy(self.updated(key, value))

  override def + [B1 >: B] (kv: (A, B1)): Map[A, B1] = newProxy(self + kv)
  override def + [B1 >: B] (elem1: (A, B1), elem2: (A, B1), elems: (A, B1) *) = newProxy(self.+(elem1, elem2, elems: _*))
  override def ++[B1 >: B](xs: GenTraversableOnce[(A, B1)]) = newProxy(self ++ xs.seq)
  override def -(key: A) = newProxy(self - key)

  override def += (kv: (A, B)) = { self += kv ; this }
  override def -= (key: A) = { self -= key ; this }
}