I’ve tried several ways to attempt to get async working in Playground. The weird thing is that it works in Project. I’ve read various reasons why that may be. Anyway, on lower numbers of inputs this sometimes will work, but higher volumes it does not. But because async does not work, this eventually will somehow clog up Xcode process that I can actually see in Activity Monitor and prevent it from opening so I’ll have to reboot. There is an answer on this website that says for Playground we wrap the code in:

The funny thing is everything executes fine. I get all my last print line but then it is crashing when it exits. If I take out: