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As noted in the comments, first take a look at <code>BOOST_FUSION_ADAPT_STRUCT</code> (and friends): <pre><code>#include <boost/fusion/include/adapt_struct.hpp> #include <string> struct Data { std::string firstMember; std::string secondMember; std::string thirdMember; }; BOOST_FUSION_ADAPT_STRUCT( Data, (std::string, firstMember) (std::string, secondMember) (std::string, thirdMember) ) </code></pre> This turns your <code>Data</code> structure into a sequence usable by Fusion: <pre><code>#include <boost/fusion/include/at_c.hpp> int main() { Data d = { "firstData", "secondData", "thirdData" }; std::cout << boost::fusion::at_c<0>(d) << std::endl; } </code></pre> This prints <code>"firstData"</code>. Change the index to refer to the members in order. There, now we can refer to members at compile-time using a number. But you wanted a name. Also noted in the comments, processing strings is a runtime feature...almost. C++11 gives us <code>constexpr</code>. It's a bit tricky, but ultimately it looks like this: <pre><code>#include <boost/fusion/include/adapt_struct.hpp> #include <boost/preprocessor/cat.hpp> #include <boost/preprocessor/repetition/repeat.hpp> #include <boost/preprocessor/seq.hpp> #include <boost/preprocessor/tuple/elem.hpp> #include <stdexcept> // and repeat for BOOST_FUSION_ADAPT_TPL_STRUCT, etc... #define REFLECT_STRUCT(NAME, ATTRIBUTES) \ REFLECT_STRUCT_DETAIL(NAME, \ ATTRIBUTES, \ BOOST_PP_SEQ_POP_FRONT( \ BOOST_PP_CAT( \ /* warning: uses fusion implementation details: */ \ BOOST_FUSION_ADAPT_STRUCT_FILLER_0(0,0)ATTRIBUTES, \ _END))) \ #define REFLECT_STRUCT_DETAIL(NAME, ATTRIBUTES, WRAPPEDATTRIBUTES) \ BOOST_FUSION_ADAPT_STRUCT(NAME, ATTRIBUTES) \ \ namespace detail \ { \ namespace BOOST_PP_CAT(reflect_, NAME) \ { \ template <int N> \ struct member_name; \ \ BOOST_PP_SEQ_FOR_EACH_I(REFLECT_STRUCT_DETAIL_MEMBER_NAME, \ BOOST_PP_EMPTY, \ WRAPPEDATTRIBUTES) \ \ template <int N> \ constexpr bool member_match_index(const std::size_t index, \ const char* const str, \ const std::size_t len) \ { \ return index == len || \ (member_name<N>::value()[index] == str[index] \ && member_match_index<N>(index + 1, str, len)); \ } \ \ template <int N> \ constexpr bool member_match(const char* const str, \ const std::size_t len) \ { \ return len == member_name<N>::value_length \ && member_match_index<N>(0, str, len); \ } \ \ constexpr int find_member(const char* const str, \ const std::size_t len) \ { \ return BOOST_PP_REPEAT(BOOST_PP_SEQ_SIZE(WRAPPEDATTRIBUTES), \ REFLECT_STRUCT_DETAIL_MEMBER_NAME_TEST, \ BOOST_PP_EMPTY) \ throw std::runtime_error("could not find " \ BOOST_PP_STRINGIZE(NAME) \ " member"); \ } \ } \ } \ \ constexpr int BOOST_PP_CAT(indexof_, NAME)(const char* const str, \ const std::size_t len) \ { \ return detail::BOOST_PP_CAT(reflect_, NAME)::find_member(str, len); \ } \ \ template <std::size_t N> \ constexpr int BOOST_PP_CAT(indexof_, NAME)(const char (&str)[N]) \ { \ return detail::BOOST_PP_CAT(reflect_, NAME)::find_member(&str[0], N); \ } #define REFLECT_STRUCT_DETAIL_EXTRACT_NAME(pair) \ BOOST_PP_STRINGIZE(BOOST_PP_TUPLE_ELEM(1, pair)) #define REFLECT_STRUCT_DETAIL_MEMBER_NAME(r, data, n, elem) \ REFLECT_STRUCT_DETAIL_MEMBER_NAME_DETAIL(n, REFLECT_STRUCT_DETAIL_EXTRACT_NAME(elem)) #define REFLECT_STRUCT_DETAIL_MEMBER_NAME_DETAIL(n, name) \ template <> \ struct member_name<n> \ { \ static constexpr std::size_t value_length = sizeof(name); \ typedef const char value_type[value_length]; \ \ static constexpr const value_type& value() \ { \ return name; \ } \ }; #define REFLECT_STRUCT_DETAIL_MEMBER_NAME_TEST(z, n, text) \ member_match<n>(str, len) ? n : </code></pre> It looks scary but its readable if you take the time to pick it apart. We have to introduce our own macros to give constant-expression access to the member names; most of the ugly comes from processing Boost.Preprocessor lists. Although Fusion does record the names during adaptation as well (see <code>boost::fusion::extension::struct_member_name</code>), they are not marked as <code>constexpr</code> so aren't usable to us, unfortunately. This gives: <pre><code>#include <boost/fusion/include/at_c.hpp> #include <iostream> #include <string> struct Data { std::string firstMember; std::string secondMember; std::string thirdMember; }; REFLECT_STRUCT( Data, (std::string, firstMember) (std::string, secondMember) (std::string, thirdMember) ) // your desired code: // (note the use of at_c ensures this is evaluated at comple-time) #define GETMEMBER(data, member) boost::fusion::at_c<indexof_Data(member)>(data) int main() { Data d = { "firstData", "secondData", "thirdData" }; std::cout << boost::fusion::at_c<indexof_Data("firstMember")>(d) << std::endl; std::cout << GETMEMBER(d, "secondMember") << std::endl; std::cout << GETMEMBER(d, "thirdMember") << std::endl; /* causes error: std::cout << GETMEMBER(d, "nonexistent_member") << std::endl; */ } </code></pre> Which I think is close to what you were after. But keep in mind this may not all be necessary: Boost.Fusion may already have what you need. It lives in the area between pure compile-time stuff (Boost.MPL) and regular run-time stuff; adapt your struct and you can already do things like iterate over it (<code>boost::fusion::for_each</code>).
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