scala.collection

trait DefaultMap

[source: scala/collection/DefaultMap.scala]

trait DefaultMap[A, +B]
extends Map[A, B]

A default map which implements the updated and - methods of maps.
Instances that inherit from DefaultMap[A, B] still have to define:

    def get(key: A): Option[B]
    def iterator: Iterator[(A, B)]

It refers back to the original map.

It might also be advisable to override foreach or size if efficient implementations can be found.

Since
2.8
Method Summary
override def + [B1 >: B](kv : (A, B1)) : Map[A, B1]
A default implementation which creates a new immutable map.
override def - (key : A) : Map[A, B]
A default implementation which creates a new immutable map.
Methods inherited from Map
empty
Methods inherited from MapLike
get (abstract), iterator (abstract), newBuilder, isEmpty, getOrElse, apply, contains, isDefinedAt, keySet, keysIterator, keys, valuesIterable, valuesIterator, values, default, filterKeys, mapValues, mapElements, updated, +, ++, ++, addString, stringPrefix, toString, hashCode, equals
Methods inherited from Subtractable
-, --, --
Methods inherited from PartialFunction
orElse, andThen
Methods inherited from Function1
compose
Methods inherited from Iterable
companion
Methods inherited from IterableLike
thisCollection, toCollection, elements, foreach, forall, exists, find, foldRight, reduceRight, toIterable, head, take, slice, takeWhile, takeRight, dropRight, copyToArray, zip, zipAll, zipWithIndex, sameElements, toStream, canEqual, view, view, first, firstOption, projection
Methods inherited from GenericTraversableTemplate
genericBuilder, unzip, flatten, transpose
Methods inherited from TraversableLike
repr, nonEmpty, size, hasDefiniteSize, ++, ++, map, flatMap, filter, filterNot, partialMap, remove, partition, groupBy, count, foldLeft, /:, :\, reduceLeft, reduceLeftOption, reduceRightOption, sum, product, min, max, headOption, tail, last, lastOption, init, drop, dropWhile, span, splitAt, copyToBuffer, copyToArray, toArray, toList, toSeq, toIndexedSeq, toSet, mkString, mkString, mkString, addString, addString, withFilter
Methods inherited from AnyRef
getClass, clone, notify, notifyAll, wait, wait, wait, finalize, ==, !=, eq, ne, synchronized
Methods inherited from Any
==, !=, isInstanceOf, asInstanceOf
Method Details
override def +[B1 >: B](kv : (A, B1)) : Map[A, B1]
A default implementation which creates a new immutable map.

override def -(key : A) : Map[A, B]
A default implementation which creates a new immutable map.