Passing myself, a struct, as a C callback context

[via Digitalmars-d-learn]

On Monday, 30 March 2015 at 02:53:36 UTC, Paul O'Neil wrote:
> I'm registering a callback with some C code.  The simplified 
> story is
> here, but the actual code is on GitHub [1] at the end if you 
> care.
>
> The call looks something like this.
>
> void register(void(*fp)(void*), void* context);
>
> I have a class that holds state for the callback and registers 
> itself:
>
> final class Klass
> {
>     void method()
>     {
>         register(callback_function, &this);
>     }
> }

`this` is already a reference. You're taking the address of that 
reference. A  simple cast should work: `cast(void*) this`.