Scala example source code file (unchecked.scala)

This example Scala source code file (unchecked.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.)

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The unchecked.scala Scala example source code

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

package scala

/** An annotation to designate that the annotated entity
 *  should not be considered for additional compiler checks.
 *  Specific applications include annotating the subject of
 *  a match expression to suppress exhaustiveness warnings, and
 *  annotating a type argument in a match case to suppress
 *  unchecked warnings.
 *
 *  Such suppression should be used with caution, without which
 *  one may encounter [[scala.MatchError]] or [[java.lang.ClassCastException]]
 *  at runtime.  In most cases one can and should address the
 *  warning instead of suppressing it.
 *
 *  {{{
 *    object Test extends App {
 *      // This would normally warn "match is not exhaustive"
 *      // because `None` is not covered.
 *      def f(x: Option[String]) = (x: @unchecked) match { case Some(y) => y }
 *      // This would normally warn "type pattern is unchecked"
 *      // but here will blindly cast the head element to String.
 *      def g(xs: Any) = xs match { case x: List[String @unchecked] => x.head }
 *    }
 * }}}
 *
 *  @since 2.4
 */
class unchecked extends scala.annotation.Annotation {}