need help to find a way to replace c macro

[Dakota]

```c
typedef union JSCFunctionType {
     JSCFunction *generic;
     JSValue (*generic_magic)(JSContext *ctx, JSValueConst 
this_val, int argc, JSValueConst *argv, int magic);
     JSCFunction *constructor;
     JSValue (*constructor_magic)(JSContext *ctx, JSValueConst 
new_target, int argc, JSValueConst *argv, int magic);
     JSCFunction *constructor_or_func;
     double (*f_f)(double);
     double (*f_f_f)(double, double);
     JSValue (*getter)(JSContext *ctx, JSValueConst this_val);
     JSValue (*setter)(JSContext *ctx, JSValueConst this_val, 
JSValueConst val);
     JSValue (*getter_magic)(JSContext *ctx, JSValueConst 
this_val, int magic);
     JSValue (*setter_magic)(JSContext *ctx, JSValueConst 
this_val, JSValueConst val, int magic);
     JSValue (*iterator_next)(JSContext *ctx, JSValueConst 
this_val,
                              int argc, JSValueConst *argv, int 
*pdone, int magic);
} JSCFunctionType;

typedef struct JSCFunctionListEntry {
     const char *name;
     uint8_t prop_flags;
     uint8_t def_type;
     int16_t magic;
     union {
         struct {
             uint8_t length; /* XXX: should move outside union */
             uint8_t cproto; /* XXX: should move outside union */
             JSCFunctionType cfunc;
         } func;
         struct {
             JSCFunctionType get;
             JSCFunctionType set;
         } getset;
         struct {
             const char *name;
             int base;
         } alias;
         struct {
             const struct JSCFunctionListEntry *tab;
             int len;
         } prop_list;
         const char *str;
         int32_t i32;
         int64_t i64;
         double f64;
     } u;
} JSCFunctionListEntry;

#define JS_CFUNC_DEF(name, length, func1) { name, 
JS_PROP_WRITABLE | JS_PROP_CONFIGURABLE, JS_DEF_CFUNC, 0, .u = { 
.func = { length, JS_CFUNC_generic, { .generic = func1 } } } }
#define JS_CFUNC_MAGIC_DEF(name, length, func1, magic) { name, 
JS_PROP_WRITABLE | JS_PROP_CONFIGURABLE, JS_DEF_CFUNC, magic, .u 
= { .func = { length, JS_CFUNC_generic_magic, { .generic_magic = 
func1 } } } }
#define JS_CFUNC_SPECIAL_DEF(name, length, cproto, func1) { name, 
JS_PROP_WRITABLE | JS_PROP_CONFIGURABLE, JS_DEF_CFUNC, 0, .u = { 
.func = { length, JS_CFUNC_ ## cproto, { .cproto = func1 } } } }
#define JS_ITERATOR_NEXT_DEF(name, length, func1, magic) { name, 
JS_PROP_WRITABLE | JS_PROP_CONFIGURABLE, JS_DEF_CFUNC, magic, .u 
= { .func = { length, JS_CFUNC_iterator_next, { .iterator_next = 
func1 } } } }
#define JS_CGETSET_DEF(name, fgetter, fsetter) { name, 
JS_PROP_CONFIGURABLE, JS_DEF_CGETSET, 0, .u = { .getset = { .get 
= { .getter = fgetter }, .set = { .setter = fsetter } } } }
#define JS_CGETSET_MAGIC_DEF(name, fgetter, fsetter, magic) { 
name, JS_PROP_CONFIGURABLE, JS_DEF_CGETSET_MAGIC, magic, .u = { 
.getset = { .get = { .getter_magic = fgetter }, .set = { 
.setter_magic = fsetter } } } }



static const JSCFunctionListEntry js_std_funcs[] = {
     JS_CFUNC_DEF("exit", 1, js_std_exit ),
     JS_CFUNC_DEF("gc", 0, js_std_gc ),
     JS_CFUNC_DEF("evalScript", 1, js_evalScript ),
     JS_CFUNC_DEF("loadScript", 1, js_loadScript ),
     JS_CFUNC_DEF("getenv", 1, js_std_getenv ),
     JS_CFUNC_DEF("setenv", 1, js_std_setenv ),
     JS_CFUNC_DEF("unsetenv", 1, js_std_unsetenv ),
     JS_CFUNC_DEF("getenviron", 1, js_std_getenviron ),
     JS_CFUNC_DEF("urlGet", 1, js_std_urlGet ),
     JS_CFUNC_DEF("loadFile", 1, js_std_loadFile ),
     JS_CFUNC_DEF("strerror", 1, js_std_strerror ),
     JS_CFUNC_DEF("parseExtJSON", 1, js_std_parseExtJSON ),

     /* FILE I/O */
     JS_CFUNC_DEF("open", 2, js_std_open ),
     JS_CFUNC_DEF("popen", 2, js_std_popen ),
     JS_CFUNC_DEF("fdopen", 2, js_std_fdopen ),
     JS_CFUNC_DEF("tmpfile", 0, js_std_tmpfile ),
     JS_CFUNC_MAGIC_DEF("puts", 1, js_std_file_puts, 0 ),
     JS_CFUNC_DEF("printf", 1, js_std_printf ),
     JS_CFUNC_DEF("sprintf", 1, js_std_sprintf ),
};

```

the js_std_funcs better to be defined as const, so in runtime the 
memory address is non-writable for some platform.


I am not sure how to translate JS_CFUNC_DEF, JS_CFUNC_MAGIC_DEF 
into D, so I can use it like c here to create a nice const array 
of JSCFunctionListEntry