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/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2003-2013, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala
package collection
package mutable
import generic._
/** A base trait for maps that can be mutated.
* $mapNote
* $mapTags
* @since 1.0
* @author Matthias Zenger
*/
trait Map[K, V]
extends Iterable[(K, V)]
// with GenMap[K, V]
with scala.collection.Map[K, V]
with MapLike[K, V, Map[K, V]] {
override def empty: Map[K, V] = Map.empty
override def seq: Map[K, V] = this
/** The same map with a given default function.
*
* Invoking transformer methods (e.g. `map`) will not preserve the default value.
*
* @param d the function mapping keys to values, used for non-present keys
* @return a wrapper of the map with a default value
*/
def withDefault(d: K => V): mutable.Map[K, V] = new Map.WithDefault[K, V](this, d)
/** The same map with a given default value.
*
* Invoking transformer methods (e.g. `map`) will not preserve the default value.
*
* @param d default value used for non-present keys
* @return a wrapper of the map with a default value
*/
def withDefaultValue(d: V): mutable.Map[K, V] = new Map.WithDefault[K, V](this, x => d)
}
/** $factoryInfo
* The current default implementation of a $Coll is a `HashMap`.
* @define coll mutable map
* @define Coll `mutable.Map`
*/
object Map extends MutableMapFactory[Map] {
/** $canBuildFromInfo */
implicit def canBuildFrom[K, V]: CanBuildFrom[Coll, (K, V), Map[K, V]] = new MapCanBuildFrom[K, V]
def empty[K, V]: Map[K, V] = new HashMap[K, V]
class WithDefault[K, V](underlying: Map[K, V], d: K => V) extends scala.collection.Map.WithDefault(underlying, d) with Map[K, V] {
override def += (kv: (K, V)) = {underlying += kv; this}
def -= (key: K) = {underlying -= key; this}
override def empty = new WithDefault(underlying.empty, d)
override def updated[V1 >: V](key: K, value: V1): WithDefault[K, V1] = new WithDefault[K, V1](underlying.updated[V1](key, value), d)
override def + [V1 >: V](kv: (K, V1)): WithDefault[K, V1] = updated(kv._1, kv._2)
override def - (key: K): WithDefault[K, V] = new WithDefault(underlying - key, d)
/** If these methods aren't overridden to thread through the underlying map,
* successive calls to withDefault* have no effect.
*/
override def withDefault(d: K => V): mutable.Map[K, V] = new WithDefault[K, V](underlying, d)
override def withDefaultValue(d: V): mutable.Map[K, V] = new WithDefault[K, V](underlying, x => d)
}
}
/** Explicit instantiation of the `Map` trait to reduce class file size in subclasses. */
abstract class AbstractMap[K, V] extends scala.collection.AbstractMap[K, V] with Map[K, V]
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