Scala example source code file (MatchError.scala)

This example Scala source code file (MatchError.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

any, matcherror, runtimeexception, throwable

The MatchError.scala Scala example source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2002-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */



package scala

/** This class implements errors which are thrown whenever an
 *  object doesn't match any pattern of a pattern matching
 *  expression.
 *
 *  @author  Matthias Zenger
 *  @author  Martin Odersky
 *  @version 1.1, 05/03/2004
 *  @since   2.0
 */
final class MatchError(obj: Any) extends RuntimeException {
  /** There's no reason we need to call toString eagerly,
   *  so defer it until getMessage is called.
   */
  private lazy val objString = {
    def ofClass = "of class " + obj.getClass.getName
    if (obj == null) "null"
    else try {
      obj.toString() + " (" + ofClass + ")"
    } catch {
      case _: Throwable => "an instance " + ofClass
    }
  }

  override def getMessage() = objString
}