How to make result of variadicsForEach be comma-separated

[pdietl]

The following nearly does what I want it to do:

#include <stdio.h>
#include <metalang99.h>

#define CASE_ENUM_VARIANT(c) case c: return #c;

#define ENUM_CONSTANT_IMPL(prefix, name) v(k##prefix##_##name)
#define ENUM_CONSTANT_ARITY 2

#define ENUM_PRINTABLE(name, ...) \
    typedef enum { \
        ML99_EVAL(ML99_variadicsForEach(ML99_appl(v(ENUM_CONSTANT), v(name)), \
           v(__VA_ARGS__))) \
    } name##_t; \
    \
    const char *name##ToString(name##_t val) \
    { \
        switch (val) \
        { \
        ML99_EVAL(ML99_variadicsForEach( \
            ML99_compose( \
                ML99_reify(v(CASE_ENUM_VARIANT)), \
                ML99_appl(v(ENUM_CONSTANT), v(name)) \
            ), \
            v(__VA_ARGS__)) \
        ) \
            default: return "Unknown"; \
        } \
    }

ENUM_PRINTABLE(Color,
    Red,
    Green,
    Blue,
    Orange,
    Purple
)

int main()
{
    Color_t c = kColor_Red;
    printf("The color is %s\n", ColorToString(c));
    return 0;
}

Output after preprocessing:

typedef enum { kColor_Red kColor_Green kColor_Blue kColor_Orange kColor_Purple } Color_t; const char *ColorToString(Color_t val) { switch (val) { case kColor_Red: return "kColor_Red"; case kColor_Green: return "kColor_Green"; case kColor_Blue: return "kColor_Blue"; case kColor_Orange: return "kColor_Orange"; case kColor_Purple: return "kColor_Purple"; default: return "Unknown"; } }
int main()
{
    Color_t c = kColor_Red;
    printf("The color is %s\n", ColorToString(c));
    return 0;
}

But I cannot figure out how to get the things inside typedef enum { ... } to be comma-separated. Any suggestions? Thanks!

[hirrolot]

Hi! Perhaps the easiest solution would be:

// Same...

#define ENUMERATE(c) c,

#define ENUM_PRINTABLE(name, ...) \
    typedef enum {  \
        ML99_EVAL(ML99_variadicsForEach( \
            ML99_compose(ML99_reify(v(ENUMERATE)), ML99_appl(v(ENUM_CONSTANT), v(name))), \
            v(__VA_ARGS__))) \
    } name##_t; \
 \
    /* Same... */

// Same...

The function main prints The color is kColor_Red on my end.

[pdietl]

Oh, thank you!