compile time 'address'

[Dominic Jones]

Hello Steve,

Thank you for your comments. A couple of replies:


On Thursday, 29 November 2018 at 16:29:00 UTC, Steven 
Schveighoffer wrote:
> 1. No you cannot read c0 or c1 at compile time, because they 
> are runtime values. You can fix this by changing them to 
> immutable or enum.

The variables are deliberately 'auto' rather than 'auto 
constexpr' as per the C++ example, so I do wish to preserve that 
in the D example. Nevertheless, in C++ querying (at least to 
perform comparison) the sudo-address, whatever it is (perhaps, 
behind the scenes it is simply a stack frame offset), is 
permitted.


> 2. D doesn't like you taking the address of compile-time 
> values, but the error message is really bad.
>
> If I do this:
>
> auto cmp(T, U)(const T t, const U u) // note, no ref
> {
>   return t == u; // note, change to value not address
> }

Presumably, this is now simply comparing values held by the 
variables, rather than the sudo-address of the original variables 
as per the C++ example?