On Friday, 4 May 2012 at 14:57:14 UTC, Timon Gehr wrote:

What would be the meaning of

void foo(ref void function() fn) { }

?

Parameter storage classes can only go before the type, while function attributes can also go after the parameter list (of the function pointer or delegate for this case). So I would think that:

   void foo(ref void function() fn) { }

The above 'foo' would receive a function pointer by reference, while:

   void foo(void function() ref fn) { }

Would receive a function pointer which returns by ref.