Following recent discussion in the General group, I had the idea
to use `opCast` in order to return a specially cooked interface
instance.
That would not be a decent solution because for example `opCast`
template func is not virtual but nonetheless I'd like to know if
this could work...
Only problem is that I cant manage to build the custom interface,
or more exactly, it is not binary compatible:
```d
import core.stdc.stdio, core.memory;
interface CanStart
{
void start();
}
class Base : CanStart
{
public void start()
{
puts("object start()");
}
public void interfaceStart()
{
puts("itf start()");
}
T opCast(T)()
{
static if (is(T == CanStart))
{
auto s = GC.malloc(size_t.sizeof*2);
auto r = cast(void**) s;
r[0] = cast(void*)this; // likely the issue
r[1] = (&interfaceStart).ptr;
auto result = *cast(CanStart*) s;
assert(result);
return result;
//assert(0, "smthg can be done here...");
}
return cast(T) this;
}
}
void main()
{
scope b = new Base;
b.start();
scope cs = cast(CanStart) b;
cs.start();
}
```
