New reorg plan

1 files changed, 69 insertions, 0 deletions

diff --git a/src/library/scala/Symbol.scala b/src/library/scala/Symbol.scala
new file mode 100644
index 0000000000..6f7ca958c7
--- /dev/null
+++ b/src/library/scala/Symbol.scala
@@ -0,0 +1,69 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2008, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+// $Id$
+
+
+package scala
+
+import scala.collection.jcl
+
+private[scala] object internedSymbols extends jcl.WeakHashMap[String, ref.WeakReference[Symbol]]
+
+/** <p>
+ *    This class provides a simple way to get unique objects for
+ *    equal strings. Since symbols are interned, they can be compared using
+ *    reference equality. Instances of
+ *    <code>Symbol</code> can be created easily with Scala's built-in
+*     quote mechanism.
+ *  </p>
+ *  <p>
+ *    For instance, the <a href="http://scala-lang.org/" target="_top">Scala</a>
+ *    term <code>'mysym</code> will invoke the constructor of the
+ *    <code>Symbol</code> class in the following way:
+ *    <code>Symbol("mysym")</code>.
+ *  </p>
+ *
+ *  @author  Martin Odersky, Iulian Dragos
+ *  @version 1.8
+ */
+@serializable
+final class Symbol private (val name: String) {
+
+  /** Converts this symbol to a string.
+   */
+  override def toString(): String = "'" + name
+
+  @throws(classOf[java.io.ObjectStreamException])
+  private def readResolve(): Any = Symbol.apply(name)
+}
+
+object Symbol {
+
+  /** <p>
+   *    Makes this symbol into a unique reference.
+   *  </p>
+   *  <p>
+   *    If two interened symbols are equal (i.e. they have the same name)
+   *    then they must be identical (wrt reference equality).
+   *  </p>
+   *
+   *  @return the unique reference to this string.
+   */
+  def apply(name: String): Symbol = internedSymbols.synchronized {
+    internedSymbols.get(name).flatMap(_.get) match {
+    case Some(sym) => sym
+    case _ =>
+      val sym = new Symbol(name)
+      internedSymbols(name) = new ref.WeakReference(sym)
+      sym
+    }
+  }
+
+  def unapply(other: Symbol): Option[String] = Some(other.name)
+}