C++ preprocessor conditional parameter

Question

Please note C++03! any C++11 solutions are not good for me, but do post them just for knowledge sake.

I know the preprocessor can do things like:

#de         


        

Answer 1

If you can use Boost, you could do this with Boost.Preprocessor:

#define BAR(X) BOOST_PP_EXPR_IF(BOOST_PP_EQUAL(X, 4), cout << "hi" << endl;)