easily convert any method/function to a delegate

[BCS]

Daniel Korsgaard wrote:
> two simple function templates that together will enable you to 
> mindlessly use delegates everywhere.
> 
> Whee first post on this NG :D
> .. hope you like it..
> 
> -------------------
>
[...]

> /// two functions that will convert any
> R delegate(P) to_delegate(R, P...)(R delegate(P) dg)
> {
>     // insanely advanced operation!
>     return dg;
> }
> 
> /// ditto
> R delegate(P) to_delegate(R, P...)(R function(P) fp)
> {
>     R delegate(P) dg;
>     dg.funcptr = fp;
>     dg.ptr = null;
>     return dg;
> }



IIRC that doesn't (quite) work because some functions pass an arg in the 
same place as methods pass "this"

However IIRC you /can/ pass the function pointer as the delegate ptr and 
then have the delegate code convert it back to the correct type and call it.

R delegate(P) to_delegate(R, P...)(R function(P) fp)
{
     auto dg = delegate R(P p)
         {return (cast(R function(P))(cast(void*)this))(p);}
     dg.ptr = cast(void*)fp;
     return dg;
}