Scala example source code file (IndexedSeqLike.scala)

This example Scala source code file (IndexedSeqLike.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

a, any, indexedseq, indexedseqlike, indexedseqview, int, repr

The IndexedSeqLike.scala Scala example source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2003-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */

package scala
package collection
package mutable

/** A subtrait of scala.collection.IndexedSeq which represents sequences
 *  that can be mutated.
 *
 *  It declares a method `update` which allows updating an element
 *  at a specific index in the sequence.
 *
 *  This trait just implements `iterator` in terms of `apply` and `length`.
 *  However, see `IndexedSeqOptimized` for an implementation trait that overrides operations
 *  to make them run faster under the assumption of fast random access with `apply`.
 *
 *  $indexedSeqInfo
 *
 *  @tparam A    the element type of the $coll
 *  @tparam Repr the type of the actual $coll containing the elements.
 *
 *  @define Coll `IndexedSeq`
 *  @define coll mutable indexed sequence
 *  @define indexedSeqInfo
 *  @author Martin Odersky
 *  @version 2.8
 *  @since   2.8
 *  @define willNotTerminateInf
 *  @define mayNotTerminateInf
 */
trait IndexedSeqLike[A, +Repr] extends Any with scala.collection.IndexedSeqLike[A, Repr] { self =>

  override protected[this] def thisCollection: IndexedSeq[A] = this.asInstanceOf[IndexedSeq[A]]
  override protected[this] def toCollection(repr: Repr): IndexedSeq[A] = repr.asInstanceOf[IndexedSeq[A]]

  /** Replaces element at given index with a new value.
   *
   *  @param idx     the index of the element to replace.
   *  @param elem    the new value.
   *  @throws   IndexOutOfBoundsException if the index is not valid.
   */
  def update(idx: Int, elem: A)

  /** Creates a view of this iterable @see Iterable.View
   */
  override def view = new IndexedSeqView[A, Repr] {
    protected lazy val underlying = self.repr
    override def iterator = self.iterator
    override def length = self.length
    override def apply(idx: Int) = self.apply(idx)
    override def update(idx: Int, elem: A) = self.update(idx, elem)
  }

  /** A sub-sequence view  starting at index `from`
   *  and extending up to (but not including) index `until`.
   *
   *  @param from   The index of the first element of the slice
   *  @param until  The index of the element following the slice
   *  @note  The difference between `view` and `slice` is that `view` produces
   *         a view of the current sequence, whereas `slice` produces a new sequence.
   *
   *  @note view(from, to)  is equivalent to view.slice(from, to)
   */
  override def view(from: Int, until: Int) = view.slice(from, until)
}