Sujet : Re: is it possible to have functions with 0, 1, or 2 args?
De : tr.17687 (at) *nospam* z991.linuxsc.com (Tim Rentsch)
Groupes : comp.lang.cDate : 11. Aug 2024, 18:43:03
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <86y153klaw.fsf@linuxsc.com>
References : 1 2
User-Agent : Gnus/5.11 (Gnus v5.11) Emacs/22.4 (gnu/linux)
ram@zedat.fu-berlin.de (Stefan Ram) writes:
Mark Summerfield <mark@qtrac.eu> wrote or quoted:
>
This does *not* work for the `va_test()` call. But if I supply 1 or 2 args
it works great.
>
Here's an
>
SSCCE, a short self-contained correct compilable example, aka,
MWE - minimal working example.
>
Some coders whip up these examples themselves for their post!
>
It's a quick and dirty demo that can be compiled and run to
show what's buggin' them.
>
In this case, it's hella clear the macros are trippin', thinkin'
the number of args is "1" when it's actually zilch, nada, zero.
>
main.c
>
#include <stdio.h>
>
#define NARGS(...) NARGS_(__VA_ARGS__, 5, 4, 3, 2, 1, 0)
#define NARGS_(_5, _4, _3, _2, _1, N, ...) N
#define va_test(...) NARGS(__VA_ARGS__)
>
int main( void ){ printf( "%d\n", va_test() ); }
>
transcript
>
1
It appears you have missed the point of the question. What is being
sought is a way to distinguish between macro calls like va_test()
and macro calls like va_test(x). The above definition of va_test()
doesn't do that.
Date | Sujet | # | | Auteur |
5 Aug 24 | is it possible to have functions with 0, 1, or 2 args? | 15 | | Mark Summerfield |
5 Aug 24 |  Re: is it possible to have functions with 0, 1, or 2 args? | 1 | | Stefan Ram |
5 Aug 24 |  Re: is it possible to have functions with 0, 1, or 2 args? | 4 | | Stefan Ram |
5 Aug 24 |   Re: is it possible to have functions with 0, 1, or 2 args? | 2 | | Stefan Ram |
8 Aug 24 |    Re: is it possible to have functions with 0, 1, or 2 args? | 1 | | Lawrence D'Oliveiro |
11 Aug 24 |   Re: is it possible to have functions with 0, 1, or 2 args? | 1 | | Tim Rentsch |
5 Aug 24 |  Re: is it possible to have functions with 0, 1, or 2 args? | 6 | | Michael S |
12 Aug 24 |   Re: is it possible to have functions with 0, 1, or 2 args? | 5 | | Tim Rentsch |
12 Aug 24 |    Re: is it possible to have functions with 0, 1, or 2 args? | 4 | | Richard Harnden |
12 Aug 24 |     Re: is it possible to have functions with 0, 1, or 2 args? | 3 | | Tim Rentsch |
12 Aug 24 |      Re: is it possible to have functions with 0, 1, or 2 args? | 2 | | Richard Harnden |
12 Aug 24 |       Re: is it possible to have functions with 0, 1, or 2 args? | 1 | | Tim Rentsch |
5 Aug 24 |  Re: is it possible to have functions with 0, 1, or 2 args? | 1 | | Stefan Ram |
5 Aug 24 |  Re: is it possible to have functions with 0, 1, or 2 args? | 1 | | Blue-Maned_Hawk |
12 Aug 24 |  Re: is it possible to have functions with 0, 1, or 2 args? | 1 | | Tim Rentsch |