Hello, I have some proto::terminal's as follows : template<typename T> struct Var { unsigned int id; }; typedef proto::terminal<Var<int> >::type int32_; typedef proto::terminal<Var<float> >::type float_; typedef proto::terminal<Var<double> >::type double_; I can write a callable transform, with templated operator() functions to handle each Var<> type as follows : struct _var_tostr : proto::callable { typedef std::string result_type; template<typename T> result_type operator()(variables::Var<T> const &v) const { std::stringstream sout; sout << "S" << v.id; return sout.str(); } template<typename T> result_type operator()(variables::VecVar<T> const &v) const { std::stringstream sout; sout << "V" << v.id; return sout.str(); } }; To activate the transform, I end up writing one rule for each Var<> type as follows : struct var_tostr : proto::or_< proto::when<proto::terminal<variables::Var<int> >, _var_tostr(proto::_value)> ,proto::when<proto::terminal<variables::Var<float> >, _var_tostr(proto::_value)> ,proto::when<proto::terminal<variables::Var<double> >, _var_tostr(proto::_value)>
{ };
This gets cumbersome when I have more Var<> types. Is there a way to not list each Var<> type in the grammar? That is, I want to match any Var<T> and just call the _var_tostr(proto::_value) transform. How can I accomplish this? Thanks, Manjunath