Generic method to display enum value names

Question

Is there a way to display the name of an enum's value? say we have:

enum fuits{
    APPLE,
    MANGO,
    ORANGE,
};

main(){
enum fruits xFruit = MANGO;
...
printf("%s",_PRINT_ENUM_STRING(xFruit));
...
}

using the preprocessor

#define _PRINT_ENUM_STRING(x) #x

won't work as we need to get the value of the variable 'x' and then convert It to string. Is this at all possible in c/C++?

Answer 1

You can use a mapping in this case.

char *a[10] = { "APPLE","MANGO","ORANGE"};

printf("%s",a[xFruit]);

Yes the preprocessor won't work unless you provide the exact enum -value.

Also check this question for more insights.

Answer 2

I've used preprocessor programming successfully to get a macro of this kind:

DEFINE_ENUM(Fruits, (Apple)(Mango)(Orange));

It does a tad more than just printing the names, but it could easily be simplified to 2 switches if necessary.

It's based on Boost.Preprocessor facilities (notably BOOST_PP_SEQ_FOREACH) which is a must have for preprocessor programming, and I find it much more elegant than the X facility and its file reinclusion system.