sources/scala/concurrent/SyncVar.scala


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/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2003-04, LAMP/EPFL               **
**  __\ \/ /__/ __ |/ /__/ __ |                                         **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
** $Id$
\*                                                                      */

package scala.concurrent;


class SyncVar[a] {

  private var isDefined: Boolean = false;
  private var value: a = _;

  def get = synchronized {
    if (!isDefined) wait();
    value
  }

  def set(x: a) = synchronized {
    value = x;
    isDefined = true;
    notifyAll()
  }

  def isSet: Boolean = synchronized {
    isDefined;
  }

  def unset = synchronized {
    isDefined = false
  }

}