For application-level concurrency I really like the way Lua explicitly excludes the most error-prone and system-dependent concurrency primitives (preemptive thr

For application-level concurrency I really like the way Lua explicitly excludes the most error-prone and system-dependent concurrency primitives (preemptive threads, mutexes, semaphores, shared memory, etc) and instead offers API's for efficient non-preemptive coroutines and states which share no memory.