On Thu, Apr 30, 2026 at 04:54:02PM +0300, Yair Lenga wrote:
> Thanks for taking the time.
> My focus is on the C compiler. Assuming the enum "metadata" is stored
> in a structure/variables that are readable by the program - can C
> programs access it ? Does it apply to "C" enums, or only to "C++" enum
> classes.
Any kind of enum.
It is roughly
#include <meta>
template <typename E>
constexpr const char *
enum_to_string (E v)
{
template for (constexpr auto e : std::define_static_array (enumerators_of
(^^E)))
if (v == [:e:])
return std::define_static_string (identifier_of (e));
return nullptr;
}
example of how it can be used:
enum E { F, G, H } i;
int
main ()
{
const char *f = enum_to_string (F);
const char *g = enum_to_string (G);
const char *h = enum_to_string (H);
const char *j = enum_to_string (i);
}
Of course, if compiled with C++26 for use in C, one would need to
wrap it in a wrapper, one per enum so that C can use it.
Also, note the above function when not evaluated at compile time doesn't
have a switch but a series of ifs, but e.g. GCC when optimizing ought to
transform that into a switch and later perhaps into an array access or
whatever is appropriate based on how dense the enumerals in the enumeration
type are, how many etc.
Jakub
