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.
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+//  iterator.hpp workarounds for non-conforming standard libraries  ---------//
+
+//  (C) Copyright Beman Dawes 2000. 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/utility for documentation.
+
+//  Revision History
+//  12 Jan 01 added <cstddef> for std::ptrdiff_t (Jens Maurer)
+//  28 Jun 00 Workarounds to deal with known MSVC bugs (David Abrahams)
+//  26 Jun 00 Initial version (Jeremy Siek)
+
+#ifndef BOOST_ITERATOR_HPP
+#define BOOST_ITERATOR_HPP
+
+#include <iterator>
+#include <cstddef>           // std::ptrdiff_t
+#include <ndnboost/config.hpp>
+
+namespace ndnboost
+{
+# if defined(BOOST_NO_STD_ITERATOR) && !defined(BOOST_MSVC_STD_ITERATOR)
+  template <class Category, class T,
+    class Distance = std::ptrdiff_t,
+    class Pointer = T*, class Reference = T&>
+  struct iterator
+  {
+    typedef T         value_type;
+    typedef Distance  difference_type;
+    typedef Pointer   pointer;
+    typedef Reference reference;
+    typedef Category  iterator_category;
+  };
+# else
+
+  // declare iterator_base in namespace detail to work around MSVC bugs which
+  // prevent derivation from an identically-named class in a different namespace.
+  namespace detail {
+   template <class Category, class T, class Distance, class Pointer, class Reference>
+#  if !defined(BOOST_MSVC_STD_ITERATOR)
+   struct iterator_base : std::iterator<Category, T, Distance, Pointer, Reference> {};
+#  else
+   struct iterator_base : std::iterator<Category, T, Distance>
+   {
+     typedef Reference reference;
+     typedef Pointer pointer;
+     typedef Distance difference_type;
+   };
+#  endif
+  }
+
+  template <class Category, class T, class Distance = std::ptrdiff_t,
+            class Pointer = T*, class Reference = T&>
+  struct iterator : ndnboost::detail::iterator_base<Category, T, Distance, Pointer, Reference> {};
+# endif
+} // namespace ndnboost
+
+#endif // BOOST_ITERATOR_HPP