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/*
* Scala (https://www.scala-lang.org)
*
* Copyright EPFL and Lightbend, Inc.
*
* Licensed under Apache License 2.0
* (http://www.apache.org/licenses/LICENSE-2.0).
*
* See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*/
package scala.collection
package mutable
import scala.annotation.tailrec
import scala.collection.generic.DefaultSerializable
import scala.collection.immutable.List
/** A simple mutable map backed by a list, so it preserves insertion order.
*
* @tparam K the type of the keys contained in this list map.
* @tparam V the type of the values assigned to keys in this list map.
*
* @define Coll `mutable.ListMap`
* @define coll mutable list map
* @define mayNotTerminateInf
* @define willNotTerminateInf
* @define orderDependent
* @define orderDependentFold
*/
@deprecated("Use an immutable.ListMap assigned to a var instead of mutable.ListMap", "2.13.0")
class ListMap[K, V]
extends AbstractMap[K, V]
with MapOps[K, V, ListMap, ListMap[K, V]]
with StrictOptimizedIterableOps[(K, V), Iterable, ListMap[K, V]]
with StrictOptimizedMapOps[K, V, ListMap, ListMap[K, V]]
with MapFactoryDefaults[K, V, ListMap, Iterable]
with DefaultSerializable {
override def mapFactory: MapFactory[ListMap] = ListMap
private[this] var elems: List[(K, V)] = List()
private[this] var siz: Int = 0
def get(key: K): Option[V] = elems find (_._1 == key) map (_._2)
def iterator: Iterator[(K, V)] = elems.iterator
final override def addOne(kv: (K, V)) = {
val (e, key0) = remove(kv._1, elems, List())
elems = (key0, kv._2) :: e
siz += 1; this
}
final override def subtractOne(key: K) = { elems = remove(key, elems, List())._1; this }
@tailrec
private def remove(key: K, elems: List[(K, V)], acc: List[(K, V)]): (List[(K, V)], K) = {
if (elems.isEmpty) (acc, key)
else if (elems.head._1 == key) { siz -= 1; (acc ::: elems.tail, elems.head._1) }
else remove(key, elems.tail, elems.head :: acc)
}
final override def clear(): Unit = { elems = List(); siz = 0 }
final override def size: Int = siz
override def knownSize: Int = size
override def isEmpty: Boolean = size == 0
override protected[this] def stringPrefix = "ListMap"
}
/** $factoryInfo
* @define Coll `mutable.ListMap`
* @define coll mutable list map
*/
@SerialVersionUID(3L)
@deprecated("Use an immutable.ListMap assigned to a var instead of mutable.ListMap", "2.13.0")
object ListMap extends MapFactory[ListMap] {
def empty[K, V]: ListMap[K, V] = new ListMap[K, V]
def from[K, V](it: IterableOnce[(K, V)]): ListMap[K,V] = Growable.from(empty[K, V], it)
def newBuilder[K, V]: Builder[(K, V), ListMap[K,V]] = new GrowableBuilder(empty[K, V])
}