[boost] Re : Re : Re : [preprocessor] ifdef equivalent inside a macro, is it possible?

Subject: [boost] Re : Re : Re : [preprocessor] ifdef equivalent inside a macro, is it possible?
From: damien benoist (damien_benoist_at_[hidden])
Date: 2011-08-11 09:05:49

> Is it possible for you to make the macro defined to some special value

> rather than being undefined ?

Yes, but I have many cases like this.
This time it will look like this
(the ifdef DEFINE_FOO is not needed):

// my default values
#define FOO1    foo1
#define FOO2   foo2
...
#define FOO42    foo42

// optional overriding values
# define FOO1_OVERRIDE (BOOST_PP_NIL)
...
# define FOO23_OVERRIDE (BOOST_PP_NIL)

// The only macro I would like to have to write
# define FOO24_OVERRIDE (myFoo24, BOOST_PP_NIL)

# define FOO25_OVERRIDE (BOOST_PP_NIL)
...
# define FOO42_OVERRIDE (BOOST_PP_NIL)


And it turns out to be simpler to write:

#define FOO1_OVERRIDE    FOO1
...
#define FOO23_OVERRIDE    FOO23
#define FOO24_OVERRIDE    myFoo24
#define FOO25_OVERRIDE    FOO25
...
#define FOO42_OVERRIDE    FOO42

Thanks for your help.