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From: Thiago Adams <thiago.adams@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: constexpr keyword is unnecessary
Date: Sat, 12 Oct 2024 10:23:32 -0300
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Em 10/12/2024 1:39 AM, Bonita Montero escreveu:
> Am 11.10.2024 um 21:30 schrieb Thiago Adams:
>> Em 10/11/2024 4:17 PM, Bonita Montero escreveu:
>>> Am 11.10.2024 um 20:11 schrieb Thiago Adams:
>>>
>>>
>>>
>>>> constant expression make sense in C. It is not new, it is very old.
>>>
>>> const has a definition and it allows non compile-time evaluated
>>> variables.
>>
>> yes. but?
> 
> With constexpr you could enforce that the expression you assign is
> compile-time evaluated. That's while constexpr would make sense.

This is already the default in C  for file scope variables and places 
where constant expression are required like enums.

Let's see local variables, that may or may not have a compile time value.

For instance


int main(){
   const int a = 1;
   constexpr int i = a; //error
}

i must be initialized with a constant expressions.
What I am suggesting is

  const int a = 1; // is a constant expression
  const int i = a; // is a constant expression


Note that C++ is already like that