Guido van Rossum added the comment: Thanks for understanding.
It's definitely subtle: there is also some code in asyncio that logs an error when a Future holding an exception becomes unreachable before anyone has asked for it; this has been a valuable debugging tool, and it depends on *not* holding references to Futures. Regarding the difference between Python 3.3 and 3.4, I don't know the exact reason, but GC definitely gets more precise with each new revision, and there are also some differences in how exactly the debug feature I just mentioned is implemented (look for _tb_logger in asyncio/futures.py). OTOH it does seem a little odd to just GC a coroutine that hasn't exited yet, and I'm not 100% convinced there *isn't* a bug here. The more I think about it, the more I think that it's suspicious that it's always the *first* iteration that gets GC'ed. So I'd like to keep this open as a reminder. Finally, I'm not sure the analogy with threads holds -- a thread manages OS resources that really do have to be destroyed explicitly, but that's not so for tasks, and any cleanup you do need can be handled using try/finally. (In general drawing analogies between threads and asyncio tasks/coroutines is probably one of the less fruitful lines of thinking about the latter; there are more differences than similarities.) ---------- resolution: invalid -> remind _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue21163> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
