scala.collection.generic.SortedSetFactory.scala Maven / Gradle / Ivy
/*
* 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
package collection
package generic
import mutable.{Builder, SetBuilder}
import scala.language.higherKinds
/** A template for companion objects of Set and subclasses thereof.
*
* @since 2.8
*/
abstract class SortedSetFactory[CC[A] <: SortedSet[A] with SortedSetLike[A, CC[A]]] {
type Coll = CC[_]
def empty[A](implicit ord: Ordering[A]): CC[A]
def apply[A](elems: A*)(implicit ord: Ordering[A]): CC[A] = {
if (elems isEmpty) empty
else (newBuilder[A](ord) ++= elems).result()
}
def newBuilder[A](implicit ord: Ordering[A]): Builder[A, CC[A]] = new SetBuilder[A, CC[A]](empty)
implicit def newCanBuildFrom[A](implicit ord : Ordering[A]) : CanBuildFrom[Coll, A, CC[A]] = new SortedSetCanBuildFrom()(ord)
class SortedSetCanBuildFrom[A](implicit ord: Ordering[A]) extends CanBuildFrom[Coll, A, CC[A]] {
private[collection] def factory = SortedSetFactory.this
private[collection] def ordering = ord
def apply(from: Coll) = newBuilder[A](ord)
def apply() = newBuilder[A](ord)
}
}