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/utility/enable_if.hpp b/ndnboost/utility/enable_if.hpp
new file mode 100644
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--- /dev/null
+++ b/ndnboost/utility/enable_if.hpp
@@ -0,0 +1,119 @@
+// Boost enable_if library
+
+// Copyright 2003 (c) The Trustees of Indiana University.
+
+// Use, modification, and distribution is 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)
+
+// Authors: Jaakko Jarvi (jajarvi at osl.iu.edu)
+// Jeremiah Willcock (jewillco at osl.iu.edu)
+// Andrew Lumsdaine (lums at osl.iu.edu)
+
+
+#ifndef BOOST_UTILITY_ENABLE_IF_HPP
+#define BOOST_UTILITY_ENABLE_IF_HPP
+
+#include "ndnboost/config.hpp"
+
+// Even the definition of enable_if causes problems on some compilers,
+// so it's macroed out for all compilers that do not support SFINAE
+
+#ifndef BOOST_NO_SFINAE
+
+namespace ndnboost
+{
+
+ template <bool B, class T = void>
+ struct enable_if_c {
+ typedef T type;
+ };
+
+ template <class T>
+ struct enable_if_c<false, T> {};
+
+ template <class Cond, class T = void>
+ struct enable_if : public enable_if_c<Cond::value, T> {};
+
+ template <bool B, class T>
+ struct lazy_enable_if_c {
+ typedef typename T::type type;
+ };
+
+ template <class T>
+ struct lazy_enable_if_c<false, T> {};
+
+ template <class Cond, class T>
+ struct lazy_enable_if : public lazy_enable_if_c<Cond::value, T> {};
+
+
+ template <bool B, class T = void>
+ struct disable_if_c {
+ typedef T type;
+ };
+
+ template <class T>
+ struct disable_if_c<true, T> {};
+
+ template <class Cond, class T = void>
+ struct disable_if : public disable_if_c<Cond::value, T> {};
+
+ template <bool B, class T>
+ struct lazy_disable_if_c {
+ typedef typename T::type type;
+ };
+
+ template <class T>
+ struct lazy_disable_if_c<true, T> {};
+
+ template <class Cond, class T>
+ struct lazy_disable_if : public lazy_disable_if_c<Cond::value, T> {};
+
+} // namespace ndnboost
+
+#else
+
+namespace ndnboost {
+
+ namespace detail { typedef void enable_if_default_T; }
+
+ template <typename T>
+ struct enable_if_does_not_work_on_this_compiler;
+
+ template <bool B, class T = detail::enable_if_default_T>
+ struct enable_if_c : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+ template <bool B, class T = detail::enable_if_default_T>
+ struct disable_if_c : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+ template <bool B, class T = detail::enable_if_default_T>
+ struct lazy_enable_if_c : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+ template <bool B, class T = detail::enable_if_default_T>
+ struct lazy_disable_if_c : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+ template <class Cond, class T = detail::enable_if_default_T>
+ struct enable_if : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+ template <class Cond, class T = detail::enable_if_default_T>
+ struct disable_if : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+ template <class Cond, class T = detail::enable_if_default_T>
+ struct lazy_enable_if : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+ template <class Cond, class T = detail::enable_if_default_T>
+ struct lazy_disable_if : enable_if_does_not_work_on_this_compiler<T>
+ { };
+
+} // namespace ndnboost
+
+#endif // BOOST_NO_SFINAE
+
+#endif