Mailman 3 July 2022 - pypy-dev

Re: Injecting an exception into another thread
by Audrey Dutcher May 10, 2023

May 10, 2023

Hi! Sorry for the delay, I didn't realize I needed to be subscribed to the mailing list to participate in conversations. My use case is that I have a gui application which runs arbitrary tasks as background threads, and needs to provide a cancel button to interrupt them. The tasks are often legacy code and/or are very difficult to find reasonable points to insert checks for interruption. Another use case would be implementing a python shell in a gui. If you want to maintain responsiveness while commands execute, they must be able to run in another thread (or another process, but this is not ideal if the shell is supposed to interact with the internals of your application). Interrupting lines with ctrl-c requires being able to send an exception to worker threads. Hope this helps! Thanks, - Audrey

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PyPy Winter Sprint + cpyext
by Stefan Beyer Dec. 21, 2022

Dec. 21, 2022

Hey everyone! Those of you who attended or followed one of the last two winter sprints in Leysin might know me, the others probably won't. I'm (still) a Master's student writing my thesis on PyPy's current issue with cross-heap cycles when using cpyext. The main point is, that they are not collected and stay around as floating garbage, even if they are not reachable any more. Correct me if I'm wrong, but I didn't notice anyone else working on that topic (and/or committing something) since I've picked it up two years ago (yeah, I know, that long ago...). I saw that you would be working on "cpyext performance and completeness" during the current winter sprint this week and thought that this might also concern my thesis. So I thought I'll give you an update. I recently pushed my current (non-optimized, breaking-some-tests, but more or less working) implementation of the "CPython-style" GC-extension for cpyext. It is still in an early stage and not all cases (legacy and non-legacy-finalizers, weakrefs) are handled. However, I picked up some pace during the last couple of weeks and I'm determined to finish this implementation during the following weeks (some quirks with the tests have been haunting me, but I think I figured most of them out by now). After that, I will implement a second alternative implementation (to compare to, mostly for the sake of my thesis), which will take some more time. I also added a couple of fancy test cases (the so called "dot-tests"), so that we can test complex object graphs a little bit easier (and also because it was kind of cool to have another language inside PyPy/RPython, even if it was only for the tests...), with more test cases to come (the current ones are a bit messy). None of the new changes concerning low-latency applications are currently integrated, but that should not be too hard. I guess it won't make much sense for me to join you at this year's winter sprint, especially as I won't be able to get there before Thursday, but I might be able to join you over the IRC channel (or some other form of communication if you like). If there is anything that is worth discussing please let me know! Also feel free to comment on my code, but beware that I might change some things once I try to do some optimizations (probably not many, but at least fix the worst issues) and make it a little bit more readable. You can find my code on the cpyext-gc-cycle branch.<https://bitbucket.org/pypy/pypy/commits/branch/cpyext-gc-cycle> Looking forward to hearing from you! Greetings, Stefan

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CFFI docs
by Alex Martelli July 21, 2022

July 21, 2022

Hi Maciej, Armin, et al! Together with co-authors I've CC'd, I'm getting close to finishing the 4th edition of "Python in a Nutshell", and in particular I'm in charge of the "extending and embedding" chapter ("chap 24" based on the 3rd Ed's number), which in the first three editions focused almost exclusively on Python's C API. Working on the 4th edition I dug deeper into CFFI and I'm getting close to being convinced that it's THE way to extend (dunno about embed?) Python -- CPython as well as of course PyPy -- putting ctypes for sure, the API likely, and maybe even Cython in the shade. HOWEVER -- I now face the task of subtly convincing people who've been mostly using (especially!) ctypes, to switch to CFFI (esp. now that they can easily download free C compilers for all platforms, inc. Windows). Alas, I don't have enough real-life CFFI experience myself (and it's hard for me to get any since I'm still working 60%-time for Google, where CLIF is THE approved way to extend Python). I wonder if any of you would like to take a look and offer suggestions about the chapter, *especially* after the way-too-miniscule coverage of CFFI. I need (for evangelism purposes!) credible examples, esp. one setting CFFI head-to-head against ctypes (but comparisons with cython and the API would be fine too -- IF I could figure out how to define completely new Python types in CFFI, which so far escapes me). If asking for your collaboration is too much, is there at least a way to get your OK about reusing, with small adaptations, some of the excellent examples you give on CFFI's docs? That would probably work better than me trying to work things out from scratch, but, without your explicit permission, it would likely break copyright or something. BTW, since we're trying to slim down the page count of the Nutshell, I suspect that ch.24 will live mostly online, accessible 100% freely, with the paper book devoting just very few pages to summarizing the options for extending and embedding and linking to the online materials. I know my co-authors (CC'd) are fine with that but I still need an official OK from O'Reilly (I think I'll get it). Just in case this makes a difference to your attitude about cooperating with us in crafting this chapter!-) Thanks, Alex

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Düsseldorf Sprint Pre-Announcement September 19-23 2022 PyPy/HPy/GraalPy/...
by Carl Friedrich Bolz-Tereick July 12, 2022

July 12, 2022

Hi all, We will have a sprint in Düsseldorf in September again, from September 19-23, 2022. I'm slightly behind in organizing, so I am already sending out the dates with this mail (I just got the confirmation for the sprint room). As usual, the sprint will take place in the CS department of Heinrich-Heine-Universität Düsseldorf and will be fully public. The plan is to have a number of other Python implementations and some HPy people join us. Some GraalPy people and HPy people will definitely be there but I am also talking to other implementations. I will post a proper announcement soon! Cheers, Carl Friedrich

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module pyaesni on pypy
by Nicola Di Bona July 1, 2022

July 1, 2022

Hi, is there a way to install the pyaesni module on pypy or is it incompatible? best regards Nicola Di Bona

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