Extension to the FFI to allow macro expansions to be avoided

[Simon Marlow]

> Alastair Reid wrote:
> > [...] where the decision to insert parens is decided by a 
> command-line flag. [...]
> 
> I'm still not convinced that any change is really necessary, 
> but I'd really
> prefer a command-line flag over a change in the FFI syntax. 
> The latter will
> lead to much more portability trouble than the former.

Adding a flag is fine by me.

Cheers,
	Simon