Disqus - Latest Comments for dhellmann

Re: Producing Results Asynchronously¶

Doug Hellmann — Sat, 28 Jan 2017 17:38:23 -0000

It's just for illustration.

Re: Composing Coroutines with Control Structures¶

Doug Hellmann — Fri, 27 Jan 2017 16:22:39 -0000

Yes, that's correct.

Re: Executing Tasks Concurrently¶

Doug Hellmann — Fri, 27 Jan 2017 16:21:52 -0000

I haven't tested any of the code under 3.4, unfortunately. It sounds like the conversion you did was incomplete, based on the error message. A string is being passed somewhere that is expecting a coroutine.

Re: Producing Results Asynchronously¶

Doug Hellmann — Tue, 17 Jan 2017 11:24:34 -0000

register_callbacks() is a coroutine, so if it's called without the await I wouldn't think it would work properly.

Re: Debugging with asyncio¶

Doug Hellmann — Tue, 17 Jan 2017 09:26:38 -0000

Yes, since inner() is a coroutine it can be used directly with await.

Re: queue — Thread-safe FIFO Implementation¶

Doug Hellmann — Sun, 15 Jan 2017 09:28:15 -0000

No, not necessarily. The GIL is held between opcode execution, not for an entire expression or statement. So it's possible for the lock to switch while computing the key to use to pass to a dictionary, for instance, changing part of the inputs to the expression. And of course operations that require updating multiple data structures atomically need to be managed with a lock.

Re: namedtuple - Python Module of the Week

Doug Hellmann — Fri, 13 Jan 2017 10:42:33 -0000

Comments here are really not the best forum for that sort of question. You may want to try posting to the python-list mailing list.

Re: Communication Between Processes - Python Module of the Week

Doug Hellmann — Fri, 06 Jan 2017 12:53:56 -0000

I haven't worked with PyGame before, so I can't help with your question. You may have better luck asking on their mailing list or on python-list.

Re: Communication Between Processes - Python Module of the Week

Doug Hellmann — Thu, 22 Dec 2016 09:17:00 -0000

Good question. It doesn't matter how you save the reference to the lock. It doesn't know what object or code path is being protected. It's up to the users of the lock to coordinate and all use the same lock instance. One convenient way to do that is to attach the lock to the object being locked so it is easy to access, but that's not a requirement.

Re: decimal – Fixed and floating point math - Python Module of the Week

Doug Hellmann — Sun, 11 Dec 2016 11:01:05 -0000

Decimals support the same formatting instructions as ints, floats, and other numerical types. https://docs.python.org/3.5...

Re: Scheduling Calls to Regular Functions¶

Doug Hellmann — Sun, 11 Dec 2016 09:33:34 -0000

Good eyes, thanks! I found similar errors in a few other files and fixed them, too.

Re: threading — Manage Concurrent Operations¶

Doug Hellmann — Sun, 11 Dec 2016 09:02:13 -0000

Thanks, it looks like at some point I adjusted the timeouts to make them shorter, but I missed one. That's fixed now.

Re: Using SSL — PyMOTW 3

Doug Hellmann — Sun, 11 Dec 2016 08:53:05 -0000

Thanks, I broke the page rendering when I changed the file headers a little. I've fixed it here, too.

Re: Asynchronous I/O Using Coroutines and Streams¶

Doug Hellmann — Sun, 11 Dec 2016 08:52:47 -0000

Thanks, I broke the page rendering when I changed the file headers a little. I've fixed it.

Re: TCP/IP Client and Server - Python Module of the Week

Doug Hellmann — Wed, 07 Dec 2016 13:06:48 -0000

You'll probably have more luck with that level of question if you ask on python-list (https://www.python.org/comm... where more folks are actively discussing design questions like this.

Re: dbhash – DBM-style API for the BSD database library¶

Doug Hellmann — Fri, 02 Dec 2016 17:30:53 -0000

Thanks for reporting this problem. I have been working on the Python 3 updates (see https://pymotw.com/3/) so I've let this part of the site get a little stale. The links should now be pointing to the right places.

Re: webbrowser – Displays web pages - Python Module of the Week

Doug Hellmann — Fri, 02 Dec 2016 17:19:31 -0000

Great example!

Re: Executing Tasks Concurrently¶

Doug Hellmann — Fri, 02 Dec 2016 08:24:14 -0000

Hmm, yes, it seems I left a bit of cruft in at least one example. Thanks for pointing it out.

Re: asyncio — Asynchronous I/O, event loop, and concurrency tools¶

Doug Hellmann — Fri, 02 Dec 2016 08:23:14 -0000

Thanks for the kind words! I'm glad you've found this helpful.

Re: selectors — I/O Multiplexing Abstractions¶

Doug Hellmann — Mon, 28 Nov 2016 08:37:25 -0000

For small amounts of data, under light load, there is not likely to be that much difference. You'll notice the difference under higher load, since buffers in the networking stack may fill up, or not, differently. The blocking socket will pause the application until more data arrives. The non-blocking socket will provide the data available, even if it is less than was requested by the read() call.

Re: unittest — Automated Testing Framework¶

Doug Hellmann — Sun, 27 Nov 2016 11:06:44 -0000

You’re absolutely right, thanks!

Re: Producing Results Asynchronously¶

Doug Hellmann — Sat, 26 Nov 2016 07:09:00 -0000

Your guess is right. The callbacks run as part of the event loop processing, so as long as control is inside one of your coroutines the callbacks won't execute. If your coroutine yields control, either by awaiting something or returning, the event loop will regain control and process the callbacks on the next iteration.

Re: warnings — Non-fatal Alerts¶

Doug Hellmann — Tue, 15 Nov 2016 13:01:17 -0000

Yes, it's less than ideal, but according to the standard library documentation it's meant to be overridden. https://docs.python.org/3.5...

Re: threading – Manage concurrent threads - Python Module of the Week

Doug Hellmann — Tue, 15 Nov 2016 12:59:35 -0000

You're right, that's a typo. I probably had an earlier version of the example using 5 threads instead of 2, and failed to update the text when I updated the code.

Re: threading – Manage concurrent threads - Python Module of the Week

Doug Hellmann — Mon, 14 Nov 2016 13:18:51 -0000

If you're working with a queue, you should look at the join() method. https://pymotw.com/2/Queue/...