const and immutable values, D vs C++?

[kerdemdemir]

On Wednesday, 4 December 2019 at 14:44:43 UTC, Ola Fosheim 
Grøstad wrote:
> When is there a noticable difference when using const values 
> instead of immutable values in a function body? And when should 
> immutable be used instead of const?
>
> f(){
>   const x = g();
>   immutable y = g();
>   ... do stuff with x and y …
> }
>
> I'm comparing D to C++ and I get the following mapping:
>
> D:
> enum constant = number
>
> C++:
> enum : decltype(number) { constant = number }
>
> D:
> auto p =  g()
>
> C++:
> auto p = g()
>
> D:
> const p = g()
>
> C++:
> const auto p = g()
>
> D:
> immutable p = g()
>
> C++:
> hmmm...
>
> Has anyone done a feature by feature comparison with C++? It 
> would be interesting to see what it looks like.

Unfortunately I am not yet good with D to answer your question .
But Ali Çehreli made some comparesions with C++.
https://dconf.org/2013/talks/cehreli.pdf
And I think you will find the answers of your questions in it 
also.