Include bind in ndnboost.
diff --git a/ndnboost/math/tools/real_cast.hpp b/ndnboost/math/tools/real_cast.hpp
new file mode 100644
index 0000000..108dcbf
--- /dev/null
+++ b/ndnboost/math/tools/real_cast.hpp
@@ -0,0 +1,29 @@
+//  Copyright John Maddock 2006.
+//  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)
+
+#ifndef BOOST_MATH_TOOLS_REAL_CAST_HPP
+#define BOOST_MATH_TOOLS_REAL_CAST_HPP
+
+#ifdef _MSC_VER
+#pragma once
+#endif
+
+namespace ndnboost{ namespace math
+{
+  namespace tools
+  {
+    template <class To, class T>
+    inline To real_cast(T t)
+    {
+       return static_cast<To>(t);
+    }
+  } // namespace tools
+} // namespace math
+} // namespace ndnboost
+
+#endif // BOOST_MATH_TOOLS_REAL_CAST_HPP
+
+
+