Re: [Boost-users] [preprocessor] Comparing strings in BOOST_PP_NOT_EQUAL

Steven Watanabe schrieb:

AMDG

Maximilian Matthe wrote:

...

Hi!

I'm developing with preprocessor a class generator, that generates the wrapper classes needed by boost.python when you want to derive in python from polymorph c++-base classes.

I would need a Macro that expands to "return" if its argument is not void. I tried the following, but that obiously does not work:

#define Return(type) \ BOOST_PP_EXPR_IF(BOOST_PP_NOT_EQUAL(type, void), return)

I made a workaround by adding an integer value to my Array that defines the methods signature. But that is redundant.

Is there a way to achieve the behaviour above?

It's possible (See BOOST_MPL_PP_TOKEN_EQUAL) but it's probably easier to use void returns:

void f();

void g() { return f(); }

In Christ, Steven Watanabe

Thanks for your advice. I'm going to use BOOST_MPL_PP_TOKEN_EQUAL. Using void returns would result in writing two functions for each function I want to wrap, so using this macro seems to be a better solution.