On Wed, 14 Aug 2024 23:10:17 +0200
Alejandro Colomar via Gcc <gcc@gcc.gnu.org> wrote:
> - Rename lengthof => elementsof. Aaron found incompatible existing
> functions called lengthof() in the wild.
Hi Alejandro,
I have a suggestion and an open-ended question.
The suggestion: Instead of elementsof, name it "countof".
I use in my code
#define COUNT_OF(A) sizeof(A) / sizeof(*(A))
i don't know why anyone does anything else. It sure would be nice to
have an integrated solution, though, so A could be either an array or a
pointer. That's been a bugaboo of mine for years.
I don't think "elementsof" is a good name because it doesn't return
elements. sizeof returns a size; countof returns a count.
"elementsof" is plural, so should return elements, plural, not a
number.
If "count" is not acceptable for some reason, then "nelemof" would at
least say what it means, albeit awkwardly.
My question regards metadata more generally. I would sincerely like to
have a way to iterate over structure members. That is, given
struct T_t { int i; char *s; };
I would like to be able to do something like
forall member in T_t:
print offset, size, type, name // of T_t
}
producing
0, 4, int, i
4, 8, char*, s
The user would use that information for I/O as kind of poor man's
iostream. Put the loop in macro, and you have an instant, consistent
way to serialize and deserialize C structs.
Has anything like that been discussed for C at the standards level, as
far as you know?
Kind regards,
--jkl
