Hi, Is it possible to use references as the type of the function wrapped by lazy function. The reason I need this is because I need to instatiate a lazy function inside a class and to a class while the class does not have yet a complete definition. The application may sound exotic but I see no intrinsic limitation why the following doesn't work. If this is not possible because an intrinsic limitation of phoenix, is there a workaround? -- Thanks -- Alfredo ... is_odd_impl is defined as in http://svn.boost.org/svn/boost/sandbox/SOC/2010/phoenix3/libs/phoenix/doc/ht... #include<iostream> #include<boost/phoenix/core.hpp> #include<boost/phoenix/function.hpp> using namespace std; using boost::phoenix::arg_names::arg1; int main(){ int cuatro = 4.; is_odd_impl ioi; clog << ioi(cuatro) << endl; boost::phoenix::function<is_odd_impl> fioi; clog << fioi(arg1)(cuatro) << endl; boost::phoenix::function<is_odd_impl&> fioi_ref(ioi); clog << fioi_ref(arg1)(cuatro) << endl; //doesn't compile !!! boost::phoenix::function<is_odd_impl const&> fioi_cref(ioi); clog << fioi_cref(arg1)(cuatro) << endl; //doesn't compile !!! return 0; } example error message: usr/include/boost/phoenix/core/preprocessed/expression_10.hpp:101:17: error: invalid initialization of reference of type ‘const is_odd_impl&’ from expression of type ‘const boost::proto::result_of::make_expr<boost::proto::tag::function, boost::phoenix::default_domain_with_basic_expr, const is_odd_impl, const boost::phoenix::actor<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::phoenix::detail::argument<1> >, 0l>
, void, void, void, void, void, void, void, void, void, void>::type’