Bonus points if it has the ability for users to define static analysis a la borrow checking.
Async makes things possible that are hard or impossible to do with synch programming.
It’s a real game changer for python especially. Cant comment on rust, hopefully its implementation is smooth.
How is this not more natural than creating various state machines and passing around all sorts of weird highly abstract Future-objects?
Async code maximizes the potential of the thread it’s running in.
This sounds like an issue with the implementation of threads and scheduling in common operating systems, and I don't see how replicating all that functionality inside of each sufficiently large programming language is remotely taken seriously.
But also, you didn't respond to what I even said. You claimed that async is 'beautiful and natural'. I disagreed. You...fell back to a performance claim that's uncontroversially true, but irrelevant to what I said.
No race conditions, no inter thread coordination, no concerns about all the weird shit that happens when doing multi threading.
Only if you limited async to only one thread on one core (why would you do that?) you could avoid that.