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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Concatenated if and preprocessor
Date: Fri, 14 Mar 2025 09:26:07 -0700
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Lynn McGuire <lynnmcguire5@gmail.com> writes:

> On 3/13/2025 4:37 PM, Tim Rentsch wrote:
>
>> pozz <pozzugno@gmail.com> writes:
>>
>>> Consider this code:
>>>
>>> if (cond1) {
>>> ...
>>> } else if (cond2) {
>>> ...
>>> } else if (cond3) {
>>> ...
>>> }
>>>
>>> I want to activate every single if with a macro preprocessor.  All the
>>> combinations are possible:  only the first, only the second, only the
>>> third, the first and second... and so on.
>>>
>>> What's the best method to have a clean code that is always compiled
>>> without errors?
>>
>>      if ( ..bypass all further tests.. ) {
>>          // for a "skip all conditional segments" case (if needed)
>>          ...
>>
>>   #if TEST_1
>>      } else if (cond1) {
>>          ...
>>   #endif
>>
>>   #if TEST_2
>>      } else if (cond2) {
>>          ...
>>   #endif
>>
>>   #if TEST_3
>>      } else if (cond3) {
>>          ...
>>   #endif
>>
>>      } else {
>>          // for a "no conditional segment" ran case (if needed)
>>          ...
>>      }
>>      >
>> Having said that, it's hard to imagine a scenario where doing
>> something like this is the best way to solve the higher level
>> problem.  It is almost certainly better to rethink the reasoning
>> that resulted in choosing this scheme, and find a way to avoid it.
>
> It is code that must run on several platforms.

Yes, I already understood that.  The point of my comment is
not to eliminate the preprocessor dependencies but to express
them in a more aesthetically pleasing way.