Re: is it possible to have functions with 0, 1, or 2 args?

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From	Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups	comp.lang.c
Subject	Re: is it possible to have functions with 0, 1, or 2 args?
Date	Sun, 11 Aug 2024 10:43:03 -0700
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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.

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Thread

is it possible to have functions with 0, 1, or 2 args? Mark Summerfield <mark@qtrac.eu> - 2024-08-05 08:26 +0000
  Re: is it possible to have functions with 0, 1, or 2 args? Michael S <already5chosen@yahoo.com> - 2024-08-05 15:19 +0300
    Re: is it possible to have functions with 0, 1, or 2 args? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-11 22:20 -0700
      Re: is it possible to have functions with 0, 1, or 2 args? Richard Harnden <richard.nospam@gmail.invalid> - 2024-08-12 09:33 +0100
        Re: is it possible to have functions with 0, 1, or 2 args? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-12 02:28 -0700
          Re: is it possible to have functions with 0, 1, or 2 args? Richard Harnden <richard.nospam@gmail.invalid> - 2024-08-12 11:37 +0100
            Re: is it possible to have functions with 0, 1, or 2 args? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-12 15:39 -0700
  Re: is it possible to have functions with 0, 1, or 2 args? Blue-Maned_Hawk <bluemanedhawk@invalid.invalid> - 2024-08-05 18:46 +0000
  Re: is it possible to have functions with 0, 1, or 2 args? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-08-07 23:04 +0000
  Re: is it possible to have functions with 0, 1, or 2 args? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-11 10:43 -0700
  Re: is it possible to have functions with 0, 1, or 2 args? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-11 22:15 -0700

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