8 ms·

Very cool! I assume that anything captured will still need to have Sync/Send?

• yakubin 4y ago
  Yes. The reason why currently you need to wrap Mutexes in Arcs is not thread-safety per se. Without std::thread::scope the Rust compiler doesn't know if the spawned threads won't outlive the Mutex (which is borrowed by the closures). So it's more about memory-safety than thread-safety in this case. std::thread::scope guarantees that the threads will be joined in the std::thread::scope, thus providing enough information to the compiler (via lifetime annotations) for it to decide that they won't outlive the Mutex, so borrowing is safe in this case. That sorted, Mutex always had Sync and Send, so everything is in place to use it from multiple threads.