On 26 October 2012 19:41, weiqingh wrote:

hi there,

I would like to use boost preprocessor to generate something like this: (for n from 0 to N with n = 2 in the following example)

template void foo(T1 t1, T2 t2)

I have tried to use BOOST_PP_ENUM_PARAMS but cannot figure out how to get both T_i and t_i changed each time. is there some other macros I can use? any help is highly appreciated.

You want BOOST_PP_ENUM_BINARY_PARAMS.

I would like to use boost preprocessor to generate something like this: (for n from 0 to N with n = 2 in the following example)

template void foo(T1 t1, T2 t2)

I have tried to use BOOST_PP_ENUM_PARAMS but cannot figure out how to get both T_i and t_i changed each time. is there some other macros I can use? any help is highly appreciated.

Well I hope this can work for you:     // This wont output a template for nullary function     #define TEMPLATE_IF(n) BOOST_PP_IF(n, BOOST_PP_TUPLE_REM(1), BOOST_PP_TUPLE_EAT(1))     #define EACH(z, n, data) \     TEMPLATE_IF(n)(template) \     void foo(BOOST_PP_ENUM_BINARY_PARAMS_Z(z, n, T, t) )     BOOST_PP_REPEAT(3, EACH, ~) This will output:     void foo( )     template< typename T0> void foo( T0 t0 )     template< typename T0 , typename T1> void foo( T0 t0 , T1 t1 )