Boost.Preprocessor has a macro BOOST_PP_INTERCEPT to eat a numeric value that it is token-concatenated onto.  Is there a similar macro that just returns the value?  I.e., some BOOST_PP_EMPTY_FOR_CONCAT such that BOOST_PP_EMPTY_FOR_CONCAT ## 3 turns into 3?  As with BOOST_PP_INTERCEPT, it only needs to work for small integer values.  Is there some other technique I can use for this?  I am using it to generate std::get<> invocations in BOOST_PP_ENUM_BINARY_PARAMS.  Thank you for your help.