On Mon, Jun 2, 2014 at 11:40 AM, Aseem Bansal <asmbans...@gmail.com> wrote: > I read in these groups that asyncio is a great addition to Python 3. I have > looked around and saw the related PEP which is quite big BTW but couldn't > find a simple explanation for why this is such a great addition. Any simple > example where it can be used? > > It can be used to have a queue of tasks? Like threads? Maybe light weight > threads? Those were my thoughts but the library reference clearly stated that > this is single-threaded. So there should be some waiting time in between the > tasks. Then what is good? > > These are just jumbled thoughts that came into my mind while trying to make > sense of usefulness of asyncio. Anyone can give a better idea?
You're right, neither the PEP nor the docs to much to motivate the module's existence. I suggest you start here: http://en.wikipedia.org/wiki/Asynchronous_I/O The asynchronous model lets you initiate a task (typically an I/O task) that would normally block, and then go on to do other things (like initiating more tasks) while waiting on that task, without having to resort to multiple threads or processes (which have the disadvantages of consuming more system resources as well as introducing the risk of race conditions and deadlocks). It does this by using callbacks; when a task is complete, a callback is called that handles its completion. Often in asynchronous code you end up with large networks of callbacks that can be confusing to follow and debug because nothing ever gets called directly. One of the significant features of the asyncio module is that it allows asynchronous programming using coroutines, where the callbacks are abstracted away and essentially have the effect of resuming the coroutine when the task completes. Thus you end up writing code that looks a lot like threaded, sequential code with none of the pitfalls. -- https://mail.python.org/mailman/listinfo/python-list
