[Boost-users] [preprocessor] Identity function for token concatenation

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. -- Jeremiah Willcock