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/function_types/detail/classifier_impl/arity20_0.hpp b/ndnboost/function_types/detail/classifier_impl/arity20_0.hpp
new file mode 100644
index 0000000..ec05bbd
--- /dev/null
+++ b/ndnboost/function_types/detail/classifier_impl/arity20_0.hpp
@@ -0,0 +1,53 @@
+
+// (C) Copyright Tobias Schwinger
+//
+// Use modification and distribution are subject to the boost Software License,
+// Version 1.0. (See http://www.boost.org/LICENSE_1_0.txt).
+
+//------------------------------------------------------------------------------
+
+// no include guards, this file is intended for multiple inclusion
+
+// input: BOOST_FT_syntax type macro to use
+// input: BOOST_FT_cc empty or cc specifier
+// input: BOOST_FT_ell empty or "..."
+// input: BOOST_FT_cv empty or cv qualifiers
+// input: BOOST_FT_flags single decimal integer encoding the flags
+// output: BOOST_FT_n number of component types (arity+1)
+// output: BOOST_FT_arity current arity
+// output: BOOST_FT_type macro that expands to the type
+// output: BOOST_FT_tplargs(p) template arguments with given prefix
+// output: BOOST_FT_params(p) parameters with given prefix
+
+# include <ndnboost/function_types/detail/classifier_impl/arity10_0.hpp>
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,11> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,12> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,13> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 , typename T13 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,14> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 , T13 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 , typename T13 , typename T14 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,15> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 , T13 , T14 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 , typename T13 , typename T14 , typename T15 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,16> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 , T13 , T14 , T15 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 , typename T13 , typename T14 , typename T15 , typename T16 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,17> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 , T13 , T14 , T15 , T16 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 , typename T13 , typename T14 , typename T15 , typename T16 , typename T17 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,18> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 , T13 , T14 , T15 , T16 , T17 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 , typename T13 , typename T14 , typename T15 , typename T16 , typename T17 , typename T18 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,19> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 , T13 , T14 , T15 , T16 , T17 , T18 BOOST_FT_ell) BOOST_FT_cv);
+template< typename R , typename T0 , typename T1 , typename T2 , typename T3 , typename T4 , typename T5 , typename T6 , typename T7 , typename T8 , typename T9 , typename T10 , typename T11 , typename T12 , typename T13 , typename T14 , typename T15 , typename T16 , typename T17 , typename T18 , typename T19 >
+typename encode_charr<BOOST_FT_flags,BOOST_FT_cc_id,20> ::type
+classifier_impl(BOOST_FT_syntax(BOOST_FT_cc, BOOST_PP_EMPTY) (T0 , T1 , T2 , T3 , T4 , T5 , T6 , T7 , T8 , T9 , T10 , T11 , T12 , T13 , T14 , T15 , T16 , T17 , T18 , T19 BOOST_FT_ell) BOOST_FT_cv);
+