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/preprocessor/control/expr_if.hpp b/ndnboost/preprocessor/control/expr_if.hpp
new file mode 100644
index 0000000..364ef59
--- /dev/null
+++ b/ndnboost/preprocessor/control/expr_if.hpp
@@ -0,0 +1,30 @@
+# /* Copyright (C) 2001
+# * Housemarque Oy
+# * http://www.housemarque.com
+# *
+# * 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)
+# */
+#
+# /* Revised by Paul Mensonides (2002) */
+#
+# /* See http://www.boost.org for most recent version. */
+#
+# ifndef BOOST_PREPROCESSOR_CONTROL_EXPR_IF_HPP
+# define BOOST_PREPROCESSOR_CONTROL_EXPR_IF_HPP
+#
+# include <ndnboost/preprocessor/config/config.hpp>
+# include <ndnboost/preprocessor/control/expr_iif.hpp>
+# include <ndnboost/preprocessor/logical/bool.hpp>
+#
+# /* BOOST_PP_EXPR_IF */
+#
+# if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_EDG()
+# define BOOST_PP_EXPR_IF(cond, expr) BOOST_PP_EXPR_IIF(BOOST_PP_BOOL(cond), expr)
+# else
+# define BOOST_PP_EXPR_IF(cond, expr) BOOST_PP_EXPR_IF_I(cond, expr)
+# define BOOST_PP_EXPR_IF_I(cond, expr) BOOST_PP_EXPR_IIF(BOOST_PP_BOOL(cond), expr)
+# endif
+#
+# endif