added code example to scaladoc comment

1 files changed, 29 insertions, 4 deletions

diff --git a/src/library/scala/unsealed.scala b/src/library/scala/unsealed.scala
index 4379ea7971..5bbe0fa3e7 100755
--- a/src/library/scala/unsealed.scala
+++ b/src/library/scala/unsealed.scala
@@ -1,7 +1,7 @@
 /*                     __                                               *\
 **     ________ ___   / /  ___     Scala API                            **
 **    / __/ __// _ | / /  / _ |    (c) 2002-2007, LAMP/EPFL             **
-**  __\ \/ /__/ __ |/ /__/ __ |                                         **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
 ** /____/\___/_/ |_/____/_/ | |                                         **
 **                          |/                                          **
 \*                                                                      */
@@ -11,8 +11,33 @@
 
 package scala
 
-/**
- * An annotation that gets applied to a selector in a match expression.
- * If it is present, exhaustiveness warnings for that expression will be suppressed.
+/** <p>
+ *    An annotation that gets applied to a selector in a match expression.
+ *    If it is present, exhaustiveness warnings for that expression will be
+ *    suppressed.
+ *  </p>
+ *  <p>
+ *    For example, compiling the code:
+ *  </p><pre>
+ *    <b>object</b> test <b>extends</b> Application {
+ *      <b>def</b> f(x: Option[int]) = x <b>match</b> {
+ *        <b>case</b> Some(y) => y
+ *      }
+ *      f(None)
+ *    }</pre>
+ *  <p>
+ *    will display the following warning:
+ *  </p><pre>
+ *    test.scala:2: warning: does not cover case {object None}
+ *      def f(x: Option[int]) = x match {
+ *                              ^
+ *    one warning found</pre>
+ *  <p>
+ *    The above message may be suppressed by substituting the expression
+ *    <code>x</code> with <code>(x: @unsealed)</code>. Then the
+ *    modified code will compile silently, but, in any case, a
+ *    <a href="MatchError.html"><code>MatchError</code></a>
+ *    will be raised at runtime.
+ *  </p>
  */
 class unsealed extends Annotation {}