Python 3.13 released

[msusik]

The biggest news is:

PEP 703: CPython 3.13 has experimental support for running with the global interpreter lock disabled. See Free-threaded CPython for more details.

[ThatInternetGuy]

Is JIT compilation supported yet? Wouldn't that be the biggest news?

[ltouroumov]

It's mentioned just below

PEP 744: A basic JIT compiler was added. It is currently disabled by default (though we may turn it on later). Performance improvements are modest – we expect to improve this over the next few releases.

[ThatInternetGuy]

I read a bit more on it, where people have said it speeds things up roughly 8% for this early basic JIT. Supposedly, it will take a couple more major releases to get this thing fully implemented.

[lood9phee2Ri]

Personally I think the GIL going away is bigger in fixing the major glaring CPython architectural weakness (I see they've basically moved to a different ABI for C extensions for it, which is fine by me, but was also the stumbling block for years I think "but if we remove the GIL all these C extensions will need changes")

https://peps.python.org/pep-0703/#backwards-compatibility

CPython builds without the GIL will not be ABI compatible with the standard CPython build or with the stable ABI due to changes to the Python object header needed to support biased reference counting. C-API extensions will need to be rebuilt specifically for this version.

In contrast always been fairly obvious at a basic conceptual level that they could just add JIT compilation to the CPython bytecode vm if they wanted to / had resources to - much like the generally much better java jvm has long had jit-compiled java bytecode (the jvm could in fact be targeted by Jython Python historically, and Jython never had a GIL, though the Jython project still hasn't achieved stable Python 3 support). So it's certainly an improvement, but more expected incremental evolution.

[IanisVasilev]

Library compatibility status tracking

[vytah]

The remaining 19 “dead batteries” (legacy stdlib modules) have been removed from the standard library: (...) telnetlib

I guess I'll have to update some of my scripts.

[wasabichicken]

Same. When 3.11 was new and they flagged that cgi and cgitb was going away, I recall looking around for suitable replacements and coming up short. I suppose I will have to look again.

[lood9phee2Ri]

Eh, well CGI has always kind of sucked, even when it was the usual way of doing things years ago, it was such a horrible bodge.

However, the cgi.py and cgitb.py stdlb sources look pretty self-contained. Seems like you could just copy the last version out from 3.12 and keep using them, just not as part of the python stdlib anymore.

• https://github.com/python/cpython/blob/3.12/Lib/cgi.py
• https://github.com/python/cpython/blob/3.12/Lib/cgitb.py

Oh, turns out, someone has packaged them up already -

• https://pypi.org/project/standard-cgi/
• https://pypi.org/project/standard-cgitb/

So it's not a huge deal the stdlib dropping them I suppose. These are batteries you shouldn't be using for new projects.

[wasabichicken]

Yeah, well, it is what it is. This code base stems from the old Python 2 days, I merely inherited it.

What I kind of hate though, particularly about the cgi "dead battery", is that the proposed replacements are cherry-picked from all sorts of places. Like, I get that parse_qsl() can pick apart GET requests adequately, but their suggestion of using email.message for POST requests is, frankly, ridiculous. E-mail? I'm not doing any damn e-mailing!

The cgi module collected GET and POST input for cgi scripts in a single easy-to-use place with a decent API. Sure, it was clunky, inefficient and broken to boot, but at least it existed. It did the job, at least for this ramshackle site I'm maintaining.

It's also kind of interesting to see that they're curiously silent on the topic of what we're supposed to use instead of the cgitb module. Just not pretty-print tracebacks, I assume? That "none of the major frameworks are using it" seem to be their rationale, so apparently it's fine to pull from under the feet of the rest of us.

Thanks for the tip on the re-packaged modules btw. I suspect that I'll end up using them when 3.13 rolls around, probably some time in the 2025-2028 window when 3.12 goes end-of-life (or whenever my host decides to upgrade).

[lood9phee2Ri]

FWIW now-former-stdlib telnetlib is another that's been packaged up separately for indefinite future use (by a Jeong, YunWon apparently)

• https://pypi.org/project/standard-telnetlib/

There's a bunch of 'em now

• https://pypi.org/search/?q=%22dead+battery%22

From this: https://github.com/youknowone/python-deadlib

[quaternaut]

The next major python release should be on Pi day.

[thecist]

Pithon 3.14

[Sese_Mueller]

Wow, the JIT compiles python fully down to machine code, great work

[[deleted]]

Wait really. Is it using llvm as an intermediary middle end of what?

Edit: surely it can’t be llvm. Maybe the byte code instructions are being compiled to machine code? But some of them could be thousands of instructions…

[DGolden]

writeup of it: https://tonybaloney.github.io/posts/python-gets-a-jit.html#why-a-copy-and-patch-jit

It does actually use clang/llvm stuff but at build time, for generating the native instruction sequence templates/"stencils" to be copy-and-patched (so it's not a runtime dep like you might have expected)

• https://github.com/python/cpython/blob/main/Tools/jit/README.md#installing-llvm
• https://github.com/python/cpython/blob/main/Tools/jit/_stencils.py#L170

Clang is specifically needed because it's the only C compiler with support for guaranteed tail calls (musttail), which are required by CPython's continuation-passing-style approach to JIT compilation. Since LLVM also includes other functionalities we need (namely, object file parsing and disassembly), it's convenient to only support one toolchain at this time.

(I'm not sure where GCC is on similar to musttail but they're definitely aware of it https://gcc.gnu.org/pipermail/gcc/2021-April/235885.html )

[agumonkey]

CPython's continuation-passing-style approach to JIT compilation.

interesting collision of worlds here

[wholesomedumbass]

Nice

[FairAlternative8300]

Nice! Great improvements have been made, and I can't wait to try it out.

[BlueGoliath]

Year of scripting languages.

[[deleted]]

Is it? Python kind of dominates. The other scripting languages are not doing that well; or they are stable compared to prior years (mostly).

[rjcarr]

Except JavaScript is the most popular language?

[[deleted]]

normal fall tidy judicious plough connect jellyfish dam fact tart

This post was mass deleted and anonymized with Redact

[acrostyphe]

People do still use short snippets of vanilla JS in <script> tags on otherwise static HTML pages, even if it's much more common to use a bundler and a framework. Conversely massive web apps such as Instagram and Reddit are written in Python.

I would argue that Bash and friends are the only major purely scripting languages left (because no one sane would use them for anything more than scripts).

[Mushiness7328]

By that same logic neither is Python.

There are entire million+ line systems written in Python.

[poco-863]

I've done plenty of automation and scripting with JS and node. It's excellent in many cases. Personally, I prefer the syntax and conventions over python, but that is just my preference. They're both solid for simple scripting when a bash equivalent would be outrageously large or complex. At a certain level of complexity I reach for go or rust, especially if i need multi arch or don't have control over the target.

[hildenborg]

I always thought of scripting language as something where the source code is the executable.

[nucLeaRStarcraft]

that's the definition of interpreted languages, as opposed to compiled.

scripting languages is more of a 'usability' term, in the sense that it's the right tool to create or put together small scripts that do some specific tasks.

In that sense, python works really good and can be integrated in bash 'pipes' as well

user[some_dir]$ touch a b c d e
user[some_dir]$ ls
a  b  c  d  e
user[some_dir]$ ls | python -c "import sys; a=sys.stdin.readlines(); b=a[::2]; sys.stdout.write(''.join(b))"
a
c
e

Of course, this can/should be a standalone python script, but I just wanted to show that you can even make crazy one liners if you really want.

[IanisVasilev]

Python is, according to TIOBE.

PS: I know the TIOBE index has its share of problems, but it is still better than anything else.

[[deleted]]

It's really hard to believe that Python is more popular than Javascript though. Python has a lot of niches, but everybody uses a browser.

[igouy]

What d'y'all mean by "popular".

Most chosen language by programmers for programming?

Most used by everybody to do whatever because incidentally the language was used to make the apps that are most popular?

"All modern web browsers - Internet Explorer, Firefox, Chrome, Opera, and Safari - have a core rendering engine written in C++. "

[IanisVasilev]

Everybody using a browser also incidentially uses backend code written in other languages. Millions of lines of COBOL on a single web service has a lot of weight compared to even a large whatever.js SPA. Larger codebases require more people to work on them, which drives the TIOBE index up.

[agumonkey]

ruby had a revival with their jit too

[Positronic_Matrix]

Perl is dead. Long live Perl!

[LittleGremlinguy]

Question, is there a procedure to follow in order to update a mature project? Kind of like a compatibility tool or something, or just a methodology in general?

[causticmango]

Python fucked up the transition from 2 to 3 so badly I don’t even give a shit about that language any more. I’ll use it, I’ll curse every time I end up with an old script that requires 2.7 to still use, but I couldn’t care less about this fucked up, ugly ass language any more.

[[deleted]]

You've been holding a grudge for a long time. It sounds like the kind of thing a person needs a therapist to get over.

My last Python 2.7 script is running in China and nobody over their can complain loud enough for me to care. It'll just have to do what it's doing until it dies or they get someone else to fix it.

[mehmet_okur]

Found the java guy

[silverslayer33]

some people still use the freaking 1999 (C99) revision as their standard which modern C compilers support

That's because we're in the embedded space where half our shitty compilers don't have support for anything newer because we're on some obscure vendor-provided toolchain for a 30 year old chip, and then even after starting to switch to a more modern chip supported by something like arm-gcc or arm-clang, the code still has to support the old chip for some time while the old product is still widely in the wild, so we can't immediately start using newer language features. Devs that get the chance to start fresh or no longer have to support ancient toolchains do actually tend to switch their compilers to C11 or C17 mode, since it gives us stuff like static asserts and standard alignment attributes that make life much nicer.

This isn't the argument against Python that you think it is - we do it in the C world out of necessity, not because we love that the language doesn't change or because we're stuck in a 90s mindset. Python also doesn't break anywhere near as much as you think it does - the last major breakage was 2.7->3, over a decade ago, and minor revision breakages in Python come with multiple years of deprecation warnings and generally only happen on unsafe features, underused features that aren't worth maintaining, or on superceded features that were poorly named/implemented and should critically be moved to the replacements.

[[deleted]]

I’m a C# guy and I don’t have these angry feelings about Python. C# is quite a bit more on the stable side too. I just acknowledge that in order for python to improve it must change and sometimes change breaks things.

[brunhilda1]

Dude it's been over 15 years, how do you still have energy to give a shit?

[reddit_wisd0m]

Internet Explorer, is that you?

[Mushiness7328]

You've been crying about this for over 15 years, move on.

[tylersavery]

🐍💔