1 files changed, 65 insertions, 0 deletions
diff --git a/src/actors/scala/actors/CanReply.scala b/src/actors/scala/actors/CanReply.scala
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+++ b/src/actors/scala/actors/CanReply.scala
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+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2005-2010, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+// $Id$
+
+package scala.actors
+
+/**
+ * The <code>CanReply</code> trait defines result-bearing message send operations.
+ *
+ * @author Philipp Haller
+ */
+trait CanReply[-T, +R] {
+
+  /**
+   * Sends <code>msg</code> to this <code>CanReply</code> and
+   * awaits reply (synchronous).
+   *
+   * @param  msg the message to be sent
+   * @return     the reply
+   */
+  def !?(msg: T): R
+
+  /**
+   * Sends <code>msg</code> to this <code>CanReply</code> and
+   * awaits reply (synchronous) within <code>msec</code>
+   * milliseconds.
+   *
+   * @param  msec the time span before timeout
+   * @param  msg  the message to be sent
+   * @return      <code>None</code> in case of timeout, otherwise
+   *              <code>Some(x)</code> where <code>x</code> is the reply
+   */
+  def !?(msec: Long, msg: T): Option[R]
+
+  /**
+   * Sends <code>msg</code> to this <code>CanReply</code> and
+   * immediately returns a future representing the reply value.
+   *
+   * @param  msg the message to be sent
+   * @return     the future
+   */
+  def !!(msg: T): () => R =
+    () => this !? msg
+
+  /**
+   * Sends <code>msg</code> to this <code>CanReply</code> and
+   * immediately returns a future representing the reply value.
+   * The reply is post-processed using the partial function
+   * <code>handler</code>. This also allows to recover a more
+   * precise type for the reply value.
+   *
+   * @param      msg the message to be sent
+   * @param  handler the function to be applied to the response
+   * @return         the future
+   */
+  def !![P](msg: T, handler: PartialFunction[R, P]): () => P =
+    () => handler(this !? msg)
+
+}