Recursive delegate type?

[WB]

Most typed programming languages, other than maybe Haskell or 
Ocaml can do it, but throwing it here, as a puzzle:


```d

alias OpCodeHandler = void function(OpCode *ops, Reg *regs, 
void*);


private string next(string offset = "1", string dispatch_table = 
"d", string ops = "ops", string pc = "pc", string args = ", 
regs") {
   return `return (cast(OpCodeHandler*)(` ~ dispatch_table ~ 
`))[*((` ~ ops ~ `) + (` ~ offset ~ `))]((` ~ ops ~ `) + (` ~ 
offset ~ `)` ~ args ~ `, (` ~ dispatch_table ~ `));`;
}


void add_int(OpCode *ops, Reg *regs, void* d) {
   regs[0].Int += 1;
   mixin(next(/*offset=*/"2"));
}
...

static __gshared OpCodeHandler[256] dispatch = [
   &add_int,
   ...
];

```

So the 3rd argument to the function (`d`), is actually of type 
`OpCodeHandler*`, but obviously that is not an option:


```d
alias OpCodeHandler = void function(OpCode *ops, Reg *regs, 
OpCodeHandler*);
```

Any ideas, how to make it prettier, and avoid casts? I doubt it 
is possible.