to yield another anecdote into this stream of feedback, i spent the better part of a day trying to figure out the answer to this question, which i only found after digging up this thread and sifting through a discussion that mostly consists of interpersonal conflict to find the information i needed.
as a low-hanging action item, can we take @John_McCall ’s reply here:
The closure is executed synchronously, without allowing any interleaving on the actor; your first code is correct.
and put it somewhere more accessible?