Scala example source code file (ReplGlobal.scala)

This example Scala source code file (ReplGlobal.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

compilationunit, compiler, console, ident, list, mode, nsc, repl, stdphase, string, tree, typer

The ReplGlobal.scala Scala example source code

/* NSC -- new Scala compiler
 * Copyright 2005-2013 LAMP/EPFL
 * @author  Paul Phillips
 */

package scala.tools.nsc
package interpreter

import typechecker.Analyzer

/** A layer on top of Global so I can guarantee some extra
 *  functionality for the repl.  It doesn't do much yet.
 */
trait ReplGlobal extends Global {
  // This exists mostly because using the reporter too early leads to deadlock.
  private def echo(msg: String) { Console println msg }

  override def abort(msg: String): Nothing = {
    echo("ReplGlobal.abort: " + msg)
    super.abort(msg)
  }

  override lazy val analyzer = new {
    val global: ReplGlobal.this.type = ReplGlobal.this
  } with Analyzer {

    override protected def findMacroClassLoader(): ClassLoader = {
      val loader = super.findMacroClassLoader
      macroLogVerbose("macro classloader: initializing from a REPL classloader: %s".format(global.classPath.asURLs))
      val virtualDirectory = globalSettings.outputDirs.getSingleOutput.get
      new util.AbstractFileClassLoader(virtualDirectory, loader) {}
    }

    override def newTyper(context: Context): Typer = new Typer(context) {
      override def typed(tree: Tree, mode: Mode, pt: Type): Tree = {
        val res = super.typed(tree, mode, pt)
        tree match {
          case Ident(name) if !tree.symbol.hasPackageFlag && !name.toString.startsWith("$") =>
            repldbg("typed %s: %s".format(name, res.tpe))
          case _ =>
        }
        res
      }
    }
  }

  object replPhase extends SubComponent {
    val global: ReplGlobal.this.type = ReplGlobal.this
    val phaseName = "repl"
    val runsAfter = List[String]("typer")
    val runsRightAfter = None
    def newPhase(_prev: Phase): StdPhase = new StdPhase(_prev) {
      def apply(unit: CompilationUnit) {
        repldbg("Running replPhase on " + unit.body)
        // newNamer(rootContext(unit)).enterSym(unit.body)
      }
    }
    // add to initial or terminal phase to sanity check Run at construction
    override val requires = List("typer")  // ensure they didn't -Ystop-after:parser
  }

  override protected def computePhaseDescriptors: List[SubComponent] = {
    addToPhasesSet(replPhase, "repl")
    super.computePhaseDescriptors
  }
}