Diesel. Yet Another Asynchronous Python Comet Library, of interest because this is the first one I’ve seen that uses Python’s generator coroutines, taking advantage of the return value of the yield statement to feed messages in to a generator function. Currently only works on Python 2.6 on Linux due to a dependency on 2.6’s epoll support.
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There are plenty of other generator coroutine based libraries before diesel. And some even have unittests.
Got any links? I've not seen one that uses the ability to pass messages in to a generator and have them returned by the yield statement before.
From your blog, it looks like cogen uses that trick. I'll check it out.
Looks like Diesel got poll and kqueue support by now as well, I added plain select() support last night too (although it seems to break epoll due to a typo *oops*, will fix tonight), check the forks on bitbucket.