Get current task ID in Chapel?

How can I find out what tasks are executing which iterations of a forall loop?

For example, I'd like to get a feel for how the different DynamicIters behave,

use DynamicIters;
var r = 1..1000;
var A: [r] int;

forall i in adaptive(r) {
       A[i] = ???;
}

I can use here.id to discover what locale a forall loop has put an iteration on, but I don't know how to "see" what task within the locale each iteration was assigned to.