1 files changed, 31 insertions, 0 deletions
diff --git a/src/library/scala/annotation/unique/package.scala b/src/library/scala/annotation/unique/package.scala
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+++ b/src/library/scala/annotation/unique/package.scala
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+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2002-2010, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+package scala.annotation
+
+/**
+ * An object that provides methods for capturing unique references, and
+ * for accessing unique fields.
+ *
+ * @author Philipp Haller
+ * @since 2.9
+ */
+package object unique {
+
+  trait Captured[A] {
+    def captured: A
+    def capturedBy[B](other: B): A = captured
+  }
+
+  implicit def mkCaptured[A](x: A) = new Captured[A] {
+    def captured: A = x
+  }
+
+  def swap[A, B <: A](to: A, from: B): A = to
+
+}