Scala example source code file (package.scala)

This example Scala source code file (package.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

anyref, boolean, list, listofnil, nil, string, stringcontext, stringcontextstripmarginops, stripmargininterpolator, unit

The package.scala Scala example source code

package scala
package reflect
package internal

import scala.language.existentials // SI-6541

package object util {
  import StringOps.longestCommonPrefix

  // An allocation-avoiding reusable instance of the so-common List(Nil).
  val ListOfNil: List[List[Nothing]] = Nil :: Nil

  def andFalse(body: Unit): Boolean = false

  // Shorten a name like Symbols$FooSymbol to FooSymbol.
  private def shortenName(name: String): String = {
    if (name == "") return ""
    val segments = (name split '$').toList
    val last     = segments.last

    if (last.length == 0)
      segments takeRight 2 mkString "$"
    else
      last
  }

  def shortClassOfInstance(x: AnyRef): String = shortClass(x.getClass)
  def shortClass(clazz: Class[_]): String = {
    val name: String = (clazz.getName split '.').last
    def isModule     = name endsWith "$"                        // object
    def isAnon       = (name split '$').last forall (_.isDigit) // anonymous class

    if (isModule)
      (name split '$' filterNot (_ == "")).last + "$"
    else if (isAnon)
      clazz.getSuperclass :: clazz.getInterfaces.toList map (c => shortClass(c)) mkString " with "
    else
      shortenName(name)
  }
  /**
   * Adds the `sm` String interpolator to a [[scala.StringContext]].
   */
  implicit class StringContextStripMarginOps(val stringContext: StringContext) extends StripMarginInterpolator
}