Pass field as a template parameter

[Ben Jones]

I'm trying to write a template function like the below... is it 
possible without using string mixins?


void fun( alias(?) field, alias p1, alias p2)()
{
     if(p1.field)
        use(p2.field);
}

called with something like


static foreach( list of fields){
   fun!(field, p1, p2)();
}

I have no idea how to specify the list of fields and I'm not sure 
if alias is the right "type" for the field template parameter.