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/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2003-2009, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
// $Id$
package scala.collection.immutable
/** This class implements empty immutable sets
* @author Martin Oderskty
* @version 1.0, 019/01/2007
*/
@serializable
class EmptySet[A] extends Set[A] {
def empty[C]: Set[C] = new EmptySet[C]
def size: Int = 0
def contains(elem: A): Boolean = false
def + (elem: A): Set[A] = new Set1(elem)
def - (elem: A): Set[A] = this
def elements: Iterator[A] = Iterator.empty
}
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