diff --git a/include/boost/iterator/interoperable.hpp b/include/boost/iterator/interoperable.hpp
index 5b9fd6f..8c7ffb1 100644
--- a/include/boost/iterator/interoperable.hpp
+++ b/include/boost/iterator/interoperable.hpp
@@ -5,32 +5,33 @@
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 #ifndef BOOST_INTEROPERABLE_23022003THW_HPP
-# define BOOST_INTEROPERABLE_23022003THW_HPP
+#define BOOST_INTEROPERABLE_23022003THW_HPP
 
-# include <boost/iterator/detail/type_traits/disjunction.hpp>
+#include <type_traits>
+#include <boost/iterator/detail/type_traits/disjunction.hpp>
 
 namespace boost {
 namespace iterators {
 
-  //
-  // Meta function that determines whether two
-  // iterator types are considered interoperable.
-  //
-  // Two iterator types A,B are considered interoperable if either
-  // A is convertible to B or vice versa.
-  // This interoperability definition is in sync with the
-  // standards requirements on constant/mutable container
-  // iterators (23.1 [lib.container.requirements]).
-  //
-  // For compilers that don't support is_convertible
-  // is_interoperable gives false positives. See comments
-  // on operator implementation for consequences.
-  //
-  template <typename A, typename B>
-  struct is_interoperable
-    : detail::disjunction<std::is_convertible<A, B>, std::is_convertible<B, A>>
-  {
-  };
+//
+// Meta function that determines whether two
+// iterator types are considered interoperable.
+//
+// Two iterator types A,B are considered interoperable if either
+// A is convertible to B or vice versa.
+// This interoperability definition is in sync with the
+// standards requirements on constant/mutable container
+// iterators (23.1 [lib.container.requirements]).
+//
+// For compilers that don't support is_convertible
+// is_interoperable gives false positives. See comments
+// on operator implementation for consequences.
+//
+template< typename A, typename B >
+struct is_interoperable :
+    public detail::disjunction< std::is_convertible< A, B >, std::is_convertible< B, A > >
+{
+};
 
 } // namespace iterators