Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

executable file 66 lines (48 sloc) 1.704 kB
/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2003-2013, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala.collection
package immutable
import generic._
/** A default map which implements the `+` and `-`
* methods of maps. It does so using the default builder for
* maps defined in the `Map` object.
* 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.
*
* @tparam A the type of the keys contained in this map.
* @tparam B the type of the values associated with the keys.
*
* @since 2.8
*/
trait DefaultMap[A, +B] extends Map[A, B] { self =>
/** A default implementation which creates a new immutable map.
*/
override def +[B1 >: B](kv: (A, B1)): Map[A, B1] = {
val b = Map.newBuilder[A, B1]
b ++= this
b += ((kv._1, kv._2))
b.result
}
/** A default implementation which creates a new immutable map.
*/
override def - (key: A): Map[A, B] = {
val b = newBuilder
for (kv <- this.seq ; if kv._1 != key) b += kv
b.result
}
}
Jump to Line
Something went wrong with that request. Please try again.