I could get something like: "-f filename (=STDIN) :" instead of "-f arg (=STDIN) :"?
No, it's not possible at the moment. Since its not a showstopper, I'd like to take some time to think about it. The typed_value class is getting too big... Surely this would not be greatly affected by something like:
class typed_value ... { public: std::string arg_name; typed_value* arg_name(const std::string& arg_name_) { arg_name = arg_name_; return this; } ... and template<class T, class charT> std::string typed_value<T, charT>::name() const { std::string arg_name_ = arg_name; if (!arg_name_.length()) arg_name_ = arg; if (!m_default_value.empty() && !m_default_value_as_text.empty()) { return arg_name_ + " (=" + m_default_value_as_text + ")"; } else { return arg_name_; } } which would be used as
value<Infile>(&forests_file)->default_value(default_in,"STDIN")
value<Infile>(&forests_file)->default_value(default_in)->arg_name("STDIN")