So, I conclude, using upvars in stream functions is inherently tricky. OK, it’s an answer, and I’ll just have to make do with that.
One open question to me is if stream operations involving hundreds of thousands of “promises” are ever going to work (i.e. not crash) in Snap!. Since you (jens)
I don’t expect you’ll search any farther for a solution (or am I jumping to conclusions now?). Hmm, I may have to accept that, too, as a fact then. BTW thanks for repairing tail call optimization!
I take it you meant “shrewd” 