Optimizing for RVO

[SVN r35249]

include/boost/fusion/sequence/adapted/array/detail/distance_impl.hpp

@@ -31,10 +31,10 @@ namespace boost { namespace fusion
 
                 call(First const&, Last const&)
                 {
-                    static typename mpl::minus<
+                    typedef typename mpl::minus<
                         typename Last::index, typename First::index>::type 
                     result;
-                    return result;
+                    return result();
                 }
             };
         };