A fusion transform_view of a random access sequence should itself be a random access sequence, and its category is random access, but it doesn't seem to implement the complete interface. For instance: struct plus1 { template<typename T> struct result { typedef T type; }; template<typename T> T operator ()(T const &t) const { return t + 1; } }; template<typename V> void bar(V const &v) { boost::fusion::at_c<1>(v); // OK boost::fusion::transform_view<V const, plus1> view(v, plus1()); boost::fusion::at_c<1>(view); // ERROR } int main() { bar(boost::fusion::make_vector(1,2,3)); return 0; } I can't randomly access elements of a transformed fusion::vector. Bug? -- Eric Niebler Boost Consulting www.boost-consulting.com