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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: constexpr keyword is unnecessary
Date: Sat, 19 Oct 2024 14:49:55 -0700
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Thiago Adams <thiago.adams@gmail.com> writes:
> Em 10/19/2024 1:53 PM, Michael S escreveu:
>> On Sat, 19 Oct 2024 12:18:04 -0300
>> Thiago Adams <thiago.adams@gmail.com> wrote:
>> 
>>> Em 10/18/2024 8:54 PM, Keith Thompson escreveu:
>>>> Thiago Adams <thiago.adams@gmail.com> writes:
>>>>> I think constexpr keyword is unnecessary.
>>>>
>>>> Sure, most language features are strictly unnecessary.
>>>>    
>>>>> Anything you do with it could/should be done with const.
>>>>
>>>> No, absolutely not.
>>>>    
>>>
>>> If not, do you have a sample where, using "const" as "constexpr",
>>> would create problems?
>>>
>>> The sample I know is VLA.
>>>
>>> const int c = 2;
>>> int a[c]; //a is VLA because c is not a constant expression.
>>>
>>>
>>> But this is not enough to convince me because it is better not to be
>>> a VLA here.
>>>
>>>
>>>
>> const int c = 2;
>> struct bar {
>>    int a[c];
>>    int b;
>> };
>> 
>
> Yes, but in this case, you're changing something that was previously
> an error into something that now works.

Or you can change something that's an error into something that works in
C23 by typing "constexpr" rather than "const".

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */