overload .

[aliak]

On Monday, 25 June 2018 at 13:37:01 UTC, Mr.Bingo wrote:
>
> One can overload assignment and dispatch so that something like
>
> A.x = ... is valid when x is not a typical member but gets 
> resolved by the above functions.
>
> Therefore, I can create a member for assignment. How can I 
> create a member for getting the value?
>
> A.x = 3; // Seems to get translated in to A.opDispatch!("x")(3)
>
> works but
>
> foo(A.x); // fails and the compiler says x does not exist
>
>
> I need something consistent with opDot. I am trying to create 
> "virtual"(not as in function) fields and I can only get 
> assignment but not accessor.

A.x is translated in to A.opDispatch!"x" with no args. So I guess 
you can overload or you can static if on a template parameter 
sequence:

import std.stdio;
struct S {
     auto opDispatch(string name, Args...)(Args args) {
         static if (!Args.length) {
             return 3;
         } else {
             // set something
         }
     }
}
void main()
{
     S s;
     s.x = 3;
     writeln(s.x);
}

Cheers,
- Ali