Scala example source code file (Names.scala)

This example Scala source code file (Names.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

context, macro, name, names, nametype, reflection, si-8425, string

The Names.scala Scala example source code

package scala.reflect.macros
package contexts

trait Names {
  self: Context =>

  import global._

  def freshNameCreator = globalFreshNameCreator

  def fresh(): String =
    freshName()

  def fresh(name: String): String =
    freshName(name)

  def fresh[NameType <: Name](name: NameType): NameType =
    freshName[NameType](name)

  def freshName(): String =
    freshName(nme.FRESH_PREFIX)

  def freshName(name: String): String = {
    // In comparison with the first version of freshName, current "fresh" names
    // at least can't clash with legible user-written identifiers and are much less likely to clash with each other.
    // It is still not good enough however, because the counter gets reset every time we create a new Global.
    //
    // This would most certainly cause problems if Scala featured something like introduceTopLevel,
    // but even for def macros this can lead to unexpected troubles. Imagine that one Global
    // creates a term of an anonymous type with a member featuring a "fresh" name, and then another Global
    // imports that term with a wildcard and then generates a "fresh" name of its own. Given unlucky
    // circumstances these "fresh" names might end up clashing.
    //
    // TODO: hopefully SI-7823 will provide an ultimate answer to this problem.
    // In the meanwhile I will also keep open the original issue: SI-6879 "c.freshName is broken".
    val prefix = if (name.endsWith("$")) name else name + "$" // SI-8425
    val sortOfUniqueSuffix = freshNameCreator.newName(nme.FRESH_SUFFIX)
    prefix + sortOfUniqueSuffix
  }

  def freshName[NameType <: Name](name: NameType): NameType =
    name.mapName(freshName(_)).asInstanceOf[NameType]
}