Simple example of how to enumerate an enum's values (preprocessor + boost.spirit)

spirit_enums.cpp

#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/phoenix_core.hpp>
#include <boost/spirit/include/phoenix_operator.hpp>
#include <boost/spirit/include/phoenix_stl.hpp>
#include <iostream>
#include <vector>
#include <string>

std::vector<std::string> parse_enum(const std::string enum_str) {
    namespace spirit = boost::spirit;
    namespace qi = spirit::qi;
    namespace nix = boost::phoenix;

    std::vector<std::string> vec;

    qi::rule<std::string::const_iterator, std::string(), qi::space_type> value
        = +qi::alnum; // \todo take assignments into account

    bool r = qi::phrase_parse(
        enum_str.begin(),                          
        enum_str.end(),                           
        qi::lit("enum") >> +qi::alnum >> '{'
                        >> value[nix::push_back(nix::ref(vec), qi::_1)] % ','
                        >> -qi::char_(',') 
                        >> '}', 
        qi::space                           
    );

    return vec;
}

// __VA_ARGS__ is used to allow comas in the enum definition
#define  REFLEXIVE_ENUM(NAME, ...) \
    const std::vector<std::string> ValuesOf##NAME = parse_enum(#__VA_ARGS__); \
    __VA_ARGS__;


// EXAMPLE:

REFLEXIVE_ENUM(Foo, // the values will be put in a vector named ValuesOfFoo
    enum Foo {
        Bjarn,
        Douglas,
        Harry
    };
);

int main() {
    std::vector<std::string>::const_iterator it;
    for (it = ValuesOfFoo.begin(); it != ValuesOfFoo.end(); it++)
        std::cout << *it << std::endl; 

    Foo bar = Douglas;

    return 0;
}