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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 18:43:14 -0300
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Em 10/12/2024 10:53 AM, Bart escreveu:
> 
> It depends on what constexpr means.

It means the initialization expression must be evaluated at compilation.
Also the declarator can be used in another expression as constant.

Sample
constexpr int a = 1;
constexpr int b = a+1;

But the expression is always something the compiler need to check if is 
constant or not.

So, what I suggest is if the init expression is a constant expression 
(something we know at compile time) then the declarator is real 
constexpr (no need for a new keyword)

For instance:

const int a = 1;
const int b = a+1;


Even if not constant, the compiler can do at compile time.
for instance.
int a = 1+2;
So this has to be done anyway.
The only difference is that using 'a' cannot be used as constant in 
another expression.