template instantiation --- having trouble therewith

[Carl Sturtivant]

On Tuesday, 3 September 2013 at 13:42:44 UTC, Manfred Nowak wrote:
> Carl Sturtivant wrote:
>
>> No it isn't according to dmd.
> dmd does not express this.
>
> according to
>> p1.d(15): Error: [...]
> dmd "cannot deduce" that `Dptr!(T, U)' might be equal to
> `int delegate(int)'
>
> -manfred

I understood that. How do I fix this? Writing muddle!(int,int) in
the unit test so there's no type inference needed gives the same 
error message.