Hello boost-users, You can download sources here: https://sourceforge.net/project/showfiles.php?group_id=198908&package_id=243070&release_id=552700 Main idea of this update is to add new macros BOOST_PP_MACRO_IF/BOOST_PP_MACRO_IIF to use BOOST_PP_IF/BOOST_PP_IIF more complex when i need to pass in multiple arguments like what: /////////////////////////////////////////////////////////////////////////////// //The same as BOOST_PP_IDENTITY, but different #define MY_PP_EVAL1(x1) x1 #define MY_PP_EVAL2(x1,x2) x1,x2 #define MY_PP_EVAL3(x1,x2,x3) x1,x2,x3 #define MY_PP_EVAL4(x1,x2,x3,x4) x1,x2,x3,x4 #define MY_PP_EVAL5(x1,x2,x3,x4,x5) x1,x2,x3,x4,x5 #define MY_PP_EVAL6(x1,x2,x3,x4,x5,x6) x1,x2,x3,x4,x5,x6 #define n 0 //basically is argument of another macro // if n == 0 -> //1,2; // if n != 0 -> //1,2,3; BOOST_PP_MACRO_IF(n, (1,2,3), (1,2), MY_PP_EVAL3, MY_PP_EVAL2); //More complex usage // if n == 0 -> //1,2; // if n == 1 -> //-1,0,1,2,3; // if n > 1 -> //-1,0,1,2,3,4; BOOST_PP_MACRO_IF(n, (-1,0, BOOST_PP_MACRO_IF(BOOST_PP_GREATER(n,1), (1,2,3,4), (1,2,3), MY_PP_EVAL4, MY_PP_EVAL3)), (1,2), BOOST_PP_IF(BOOST_PP_GREATER(n,1), MY_PP_EVAL6, MY_PP_EVAL5), MY_PP_EVAL2); /////////////////////////////////////////////////////////////////////////////// I uses it to properly generate template classes implementations. PS: This is slightly different than BOOST_PP_IF(n, BOOST_PP_IDENTITY(x), BOOST_PP_EMPTY)() cause x can have multiple values and used as an expression to subsequent macro. -- Best regards, Andry mailto:andry@inbox.ru