From f6b18c709794b4d90e5d7b2c4f2a653ec933e95a Mon Sep 17 00:00:00 2001
From: arvidn <arvid@cs.umu.se>
Date: Sun, 22 May 2016 20:35:04 -0400
Subject: [PATCH] improve documentation for alert_cast

---
 include/libtorrent/alert.hpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/libtorrent/alert.hpp b/include/libtorrent/alert.hpp
index ab6cba6cb..06b48eea5 100644
--- a/include/libtorrent/alert.hpp
+++ b/include/libtorrent/alert.hpp
@@ -299,8 +299,12 @@ namespace libtorrent {
 		time_point m_timestamp;
 	};
 
-// When you get an alert, you can use ``alert_cast<>`` to attempt to cast the pointer to a
-// more specific alert type, in order to query it for more information.
+// When you get an alert, you can use ``alert_cast<>`` to attempt to cast the
+// pointer to a specific alert type, in order to query it for more
+// information.
+// 
+// .. note::
+//   ``alert_cast<>`` can only cast to an exact alert type, not a base class
 template <class T> T* alert_cast(alert* a)
 {
 	if (a == 0) return 0;