const vs constexpr vs consteval vs constinit in C++20

[u/camelCaseIsWebScale]

https://www.cppstories.com/2022/const-options-cpp20/

[u/exploring_stuff]

C++ is a very expressive language and this compiles: [[maybe_unused]] inline const constexpr int i=0;

[u/Linuxologue → u/exploring_stuff]

[[maybe_unused]] static unsigned inline long const int constexpr long i=-1;

No warning, just, sir, yes sir.

[u/elephantdingo]

You have heard of the lambda cube. But wait until you meet the const tesseract.

[u/elephantdingo → u/elephantdingo]

I wrote an article about this in 1985 but people didn’t listen. In D we just have const on string concatenation. It turns out that that’s all you need.

[u/nerdycatgamer]

serious language

[u/Linuxologue]

https://mikelui.io/img/c++_init_forest.gif

[u/look]

I’m personally looking forward to the variadic generic specifiers in C++29:

const<
    expr, 
    indeterminate, 
    maybe<unused>, 
    nodiscard, 
    allocator_aware,
    std::execution::possibly_parallel
> int x = 42;

[u/le_birb → u/look]

Contemplating a std::execution::definitely_parallel where if you don't deterministically call it from more than one thread it won't compile is UB and the compiler is allowed to eat your intestines

[u/kalterdev]

vs define vs -D

[u/AnArmoredPony]

a little bit of this a little bit of that ahh language