In common.h, define func_lib for function objects.  In configure.ac, define HAVE_STD_FUNCTION and HAVE_BOOST_FUNCTION.  Include function headers in ndnboost.
diff --git a/ndnboost/type_traits/decay.hpp b/ndnboost/type_traits/decay.hpp
new file mode 100644
index 0000000..442367e
--- /dev/null
+++ b/ndnboost/type_traits/decay.hpp
@@ -0,0 +1,44 @@
+//  (C) Copyright John Maddock & Thorsten Ottosen 2005.
+//  Use, modification and distribution are subject to 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/type_traits for most recent version including documentation.
+
+
+#ifndef BOOST_TT_DECAY_HPP_INCLUDED
+#define BOOST_TT_DECAY_HPP_INCLUDED
+
+#include <ndnboost/type_traits/config.hpp>
+#include <ndnboost/type_traits/is_array.hpp>
+#include <ndnboost/type_traits/is_function.hpp>
+#include <ndnboost/type_traits/remove_bounds.hpp>
+#include <ndnboost/type_traits/add_pointer.hpp>
+#include <ndnboost/type_traits/remove_reference.hpp>
+#include <ndnboost/mpl/eval_if.hpp>
+#include <ndnboost/mpl/identity.hpp>
+
+namespace ndnboost 
+{
+
+    template< class T >
+    struct decay
+    {
+    private:
+        typedef BOOST_DEDUCED_TYPENAME remove_reference<T>::type Ty;
+    public:
+        typedef BOOST_DEDUCED_TYPENAME mpl::eval_if< 
+            is_array<Ty>,
+            mpl::identity<BOOST_DEDUCED_TYPENAME remove_bounds<Ty>::type*>,
+            BOOST_DEDUCED_TYPENAME mpl::eval_if< 
+                is_function<Ty>,
+                add_pointer<Ty>,
+                mpl::identity<Ty>
+            >
+        >::type type;
+    };
+    
+} // namespace ndnboost
+
+
+#endif // BOOST_TT_DECAY_HPP_INCLUDED