Class Arg

tests/catch.h:4226–4259

    class CommandLine {

        struct Arg : CommonArgProperties<ConfigT>, OptionArgProperties, PositionalArgProperties {
            Arg() {}
            Arg( Detail::BoundArgFunction<ConfigT> const& _boundField ) : CommonArgProperties<ConfigT>( _boundField ) {}

            using CommonArgProperties<ConfigT>::placeholder; // !TBD

            std::string dbgName() const {
                if( !longName.empty() )
                    return "--" + longName;
                if( !shortNames.empty() )
                    return "-" + shortNames[0];
                return "positional args";
            }
            std::string commands() const {
                std::ostringstream oss;
                bool first = true;
                std::vector<std::string>::const_iterator it = shortNames.begin(), itEnd = shortNames.end();
                for(; it != itEnd; ++it ) {
                    if( first )
                        first = false;
                    else
                        oss << ", ";
                    oss << "-" << *it;
                }
                if( !longName.empty() ) {
                    if( !first )
                        oss << ", ";
                    oss << "--" << longName;
                }
                if( !placeholder.empty() )
                    oss << " <" << placeholder << ">";
                return oss.str();
            }
        };

        typedef CLARA_AUTO_PTR( Arg ) ArgAutoPtr;