Why we cannot use string in mixins?

[Jesse Phillips via Digitalmars-d-learn]

On Sunday, 28 February 2016 at 03:08:14 UTC, mahdi wrote:
> Thanks.
>
> So the author was plain wrong about using enums instead of 
> strings. The misconception is due to assuming we can use 
> `string` variables at compile time but we cannot (as they are 
> run-time data).

Not exactly either.

     #define str "My string for use"

In C people know the processor which creates a "manifest const." 
In D, it was chosen to reuse enum as the keyword to declare 
manifest const.

     enum string str = "My string for use";

But in D, we don't required declaring the type everywhere so you 
can just specify a storage class:

     const str = "My string for use";

Combine the things together and you create a compile time string 
without specifying that the type is string.

     enum str = "My string for use";