Hi, Would it be possible to add BOOST_PP_RESET_COUNTER() macro. The effect is to reset BOOST_PP_COUNTER to zero. These lines of code can do the job: #undef BOOST_PP_COUNTER #define BOOST_PP_COUNTER 0 There are several uses of this facility. For example I want to be sure, that the counter starts at zero when I use it first time in my header, regardless of the other inclusions. Implementation can be similar to BOOST_PP_UPDATE_COUNTER(). new file boost/preprocessor/slot/detail/reset_counter.hpp: #undef BOOST_PP_COUNTER #define BOOST_PP_COUNTER 0 new macro in boost/preprocessor/slot/counter.hpp: #define BOOST_PP_RESET_COUNTER \ <boost/preprocessor/slot/detail/reset_counter.hpp> usage: #include <boost/preprocessor/slot/counter.hpp> BOOST_PP_COUNTER // 0 #include BOOST_PP_UPDATE_COUNTER() BOOST_PP_COUNTER // 1 #include BOOST_PP_UPDATE_COUNTER() BOOST_PP_COUNTER // 2 #include BOOST_PP_RESET_COUNTER() BOOST_PP_COUNTER // 0 Regards, Pavol