Added boost header

test/external/boost/signals2/detail/null_output_iterator.hpp

@@ -0,0 +1,34 @@
+/*
+  An output iterator which simply discards output.
+*/
+// Copyright Frank Mori Hess 2008.
+// Distributed under the Boost Software License, Version
+// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+// See http://www.boost.org/libs/signals2 for library home page.
+
+#ifndef BOOST_SIGNALS2_NULL_OUTPUT_ITERATOR_HPP
+#define BOOST_SIGNALS2_NULL_OUTPUT_ITERATOR_HPP
+
+#include <boost/function_output_iterator.hpp>
+
+namespace boost
+{
+  namespace signals2
+  {
+    namespace detail
+    {
+      class does_nothing
+      {
+      public:
+        template<typename T>
+          void operator()(const T&) const
+          {}
+      };
+      typedef boost::function_output_iterator<does_nothing> null_output_iterator;
+    } // namespace detail
+  } // namespace signals2
+} // namespace boost
+
+#endif  // BOOST_SIGNALS2_NULL_OUTPUT_ITERATOR_HPP