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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: Mon, 12 Aug 2024 15:39:10 -0700
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Richard Harnden <richard.nospam@gmail.invalid> writes:

> On 12/08/2024 10:28, Tim Rentsch wrote:
>
>> Richard Harnden <richard.nospam@gmail.invalid> writes:
>>
>>> On 12/08/2024 06:20, Tim Rentsch wrote:
>>>
>>>> Michael S <already5chosen@yahoo.com> writes:
>>>>
>>>>> On Mon, 05 Aug 2024 08:26:04 +0000
>>>>> Mark Summerfield <mark@qtrac.eu> wrote:
>>>>>
>>>>> According to my understanding, vararg functions without arguments will
>>>>> become possible in C23.  But since fully functional C23 compilers do not
>>>>> exist yet, right now the answer to your question is "No".
>>>>
>>>> Even in C99 varargs functions can be called without arguments.
>>>> The question here is more subtle.  In fact it is possible even
>>>> in C99 and C11 to do what he wants, but it isn't easy, and it
>>>> is far from obvious how to go about it.  Still, if the question
>>>> is "can this be done?", the answer is Yes even now.
>>>
>>> How does va_start know where to, um, start from if there's no last
>>> named argument?
>>
>> Sorry, I meant to say macros, not functions (using ... and __VA_ARGS__).
>> The original question is about macro definitions, not function
>> definitions, and I didn't read carefully enough.
>
> No worries.
>
> So ... how can you do it with macros?

I'm still working on preparing an answer to that question.

> And, even if it's possible, is it a good idea?

An excellent question.  I expect there are two schools of thought. :)