[issue42128] Structural Pattern Matching (PEP 634)

Change by Andrei Kulakov : -- nosy: +andrei.avk nosy_count: 13.0 -> 14.0 pull_requests: +25916 pull_request: https://github.com/python/cpython/pull/27384 ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

Change by Saiyang Gou : -- nosy: +gousaiyang nosy_count: 12.0 -> 13.0 pull_requests: +24335 pull_request: https://github.com/python/cpython/pull/25642 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Change by Brandt Bucher : -- stage: patch review -> resolved status: open -> closed ___ Python tracker ___ ___ Python-bugs-list

[issue42128] Structural Pattern Matching (PEP 634)

Batuhan Taskaya added the comment: > Actually, I didn't see that there are still 2 open linked PRs. I'll wait > until those are merged. I've moved the AST validator to its own separate issue so feel free to close this Brandt! -- ___ Python

[issue42128] Structural Pattern Matching (PEP 634)

Change by Batuhan Taskaya : -- pull_requests: -23539 ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: New changeset f84d5a113680c5a6aaaf9130aed7a34d611748ff by Brandt Bucher in branch 'master': bpo-42128: __match_args__ can't be a list anymore (GH-25203) https://github.com/python/cpython/commit/f84d5a113680c5a6aaaf9130aed7a34d611748ff --

[issue42128] Structural Pattern Matching (PEP 634)

Change by Brandt Bucher : -- pull_requests: +23942 pull_request: https://github.com/python/cpython/pull/25203 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Change by Ken Jin : -- pull_requests: +23927 pull_request: https://github.com/python/cpython/pull/25185 ___ Python tracker ___ ___

[issue42128] Structural Pattern Matching (PEP 634)

Pablo Galindo Salgado added the comment: New changeset 08fb8ac99ab03d767aa0f1cfab3573eddf9df018 by Pablo Galindo in branch 'master': bpo-42128: Add 'missing :' syntax error message to match statements (GH-24733)

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Actually, I didn't see that there are still 2 open linked PRs. I'll wait until those are merged. -- ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: Yeah, feel free to close this issue. -- ___ Python tracker ___ ___ Python-bugs-list mailing

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Also, given that pattern matching is now shipped and documented, perhaps this issue should be closed? At this point I think dedicated issues are probably better for any new bugs/enhancements/etc. -- ___ Python

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Cool. Today or tomorrow I'll create an issue in Guido's patma repo and we can move our discussion there. I'll also create a branch and add you to my fork. -- ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

Batuhan Taskaya added the comment: > @BTaskaya, do you have any interest in helping me iterate on new AST nodes? Sure! -- ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: @BTaskaya, do you have any interest in helping me iterate on new AST nodes? -- ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Yup, I agree we should explore this area further. See my comment here on Adrian’s mypy PR: https://github.com/python/mypy/pull/10191#issuecomment-797841945 -- ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: This does point out that the ast structure is a liability, and we won't be able to easily change it, since mypy and IIRC many linters use the ast module. So I think that maybe we need to think more carefully about what the *proper* ast structure is, rather

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Not a much thought went into that decision, honestly. The main reason I chose an identifier there was because "as" always stores a simple name, so allowing it to potentially be other contexts or expressions (which are illegal) just seemed to create

[issue42128] Structural Pattern Matching (PEP 634)

Adrian Freund added the comment: Thanks for the response. Looks like I overlooked the imports, global, nonlocal, ... because I only searched for usages of identifier, but they use lists of identifiers. In that case I agree that it isn't inconsistent. --

[issue42128] Structural Pattern Matching (PEP 634)

Batuhan Taskaya added the comment: > This seams really inconsistent with the rest of the ast, where identifiers > are always wrapped in a ast.Name object. The only other exception to this is > ast.Attribute. import ... as from ... import ... as try: ... except ... as : ... global

[issue42128] Structural Pattern Matching (PEP 634)

Adrian Freund added the comment: For the last few days I've been working with pattern matching and it's ast for a bit, while trying to add support for it to mypy. During this I noticed an inconsistency in the ast: ast.MatchAs has an attribute name which is of type identifier (in C) and type

[issue42128] Structural Pattern Matching (PEP 634)

Change by Batuhan Taskaya : -- pull_requests: +23539 pull_request: https://github.com/python/cpython/pull/24771 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Pablo Galindo Salgado added the comment: New changeset 0632b1012d4dfa81ffef0d686a4710f6134f77a8 by Pablo Galindo in branch 'master': bpo-42128: Add __match_args__ to structseq-based classes (GH-24732) https://github.com/python/cpython/commit/0632b1012d4dfa81ffef0d686a4710f6134f77a8

[issue42128] Structural Pattern Matching (PEP 634)

Change by Pablo Galindo Salgado : -- pull_requests: +23504 pull_request: https://github.com/python/cpython/pull/24733 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Pablo Galindo Salgado added the comment: Opened https://github.com/python/cpython/pull/24732 > I'm also not entirely sure how "unnamed fields" work, or what they're used > for. Presumably, we'd want to end the __match_args__ tuple upon hitting one > of these? AFAIK, they should be just

[issue42128] Structural Pattern Matching (PEP 634)

Change by Pablo Galindo Salgado : -- pull_requests: +23503 pull_request: https://github.com/python/cpython/pull/24732 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Yeah, probably. I'm not too familiar with the design of those objects... would it make more sense to have the implementation be a single descriptor shared by all derived types, or should we precompute the tuple of strings when each new type is defined? I'm

[issue42128] Structural Pattern Matching (PEP 634)

Raymond Hettinger added the comment: Should __match_args__ be added to Objects/structseq.c ? -- nosy: +rhettinger ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: I'm currently working on some performance benchmarks for PEP 634: https://github.com/brandtbucher/patmaperformance Hopefully they will help inform future improvements. I already have benchmarks for class patterns and mapping patterns, and am still searching

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: New changeset a22bca6b1e2f3dc11a58f3e5ef5c22e26b8a2d80 by Daniel F Moisset in branch 'master': bpo-42128: Add documentation for pattern matching (PEP 634) (#24664) https://github.com/python/cpython/commit/a22bca6b1e2f3dc11a58f3e5ef5c22e26b8a2d80

[issue42128] Structural Pattern Matching (PEP 634)

Carol Willing added the comment: New changeset a8e2615aa885a121b8cf8e9cd07696207356a25a by Pablo Galindo in branch 'master': bpo-42128: Add documentation for the new match-based AST nodes (GH-24673) https://github.com/python/cpython/commit/a8e2615aa885a121b8cf8e9cd07696207356a25a

[issue42128] Structural Pattern Matching (PEP 634)

Change by Pablo Galindo Salgado : -- pull_requests: +23458 pull_request: https://github.com/python/cpython/pull/24673 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Thanks Pablo! > If you'd like to take it on feel free, if not I'll create a PR next weekend > with tests (probably after release, though I believe it is not a blocker as > is). No problem, I'm pretty busy too. Next weekend is fine. --

[issue42128] Structural Pattern Matching (PEP 634)

Pablo Galindo Salgado added the comment: I can pick up the AST docs PR -- ___ Python tracker ___ ___ Python-bugs-list mailing list

[issue42128] Structural Pattern Matching (PEP 634)

Batuhan Taskaya added the comment: > @BTaskaya, do you think you'll have time to open a PR with your AST validator > this weekend? It looks good to me (assuming tests pass). Unfortunately not. I believe it still lacks tests for invalid cases, but other than that should work. If you'd like

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: @BTaskaya, do you think you'll have time to open a PR with your AST validator this weekend? It looks good to me (assuming tests pass). Also, we should add the AST docs to our documentation to-do list (should be just adding entries for ast.Match, ast.MatchAs,

[issue42128] Structural Pattern Matching (PEP 634)

Carol Willing added the comment: Folks, The What's New PR is open now. I've tried to focus more on the data type/shape examples over literal example. -- ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

Change by Carol Willing : -- pull_requests: +23452 pull_request: https://github.com/python/cpython/pull/24667 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Change by Daniel Moisset : -- pull_requests: +23450 pull_request: https://github.com/python/cpython/pull/24664 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Daniel Moisset added the comment: Thanks @xtreak, I'll make some changes in these sections too. The docs are coming along well, there's still some refinement to do in the compound statements section (it's there, but looks to big), I'll submit a draft PR during the weekend so interested

[issue42128] Structural Pattern Matching (PEP 634)

Karthikeyan Singaravelan added the comment: I am not sure if this was mentioned. There are a couple of places where switch/case is mentioned in the docs and it will be good if these places were updated to the tutorial or PEP.

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: New changeset 145bf269df3530176f6ebeab1324890ef7070bf8 by Brandt Bucher in branch 'master': bpo-42128: Structural Pattern Matching (PEP 634) (GH-22917) https://github.com/python/cpython/commit/145bf269df3530176f6ebeab1324890ef7070bf8 --

[issue42128] Structural Pattern Matching (PEP 634)

Daniel Moisset added the comment: Note: I will NOT write something for "What's New in 3.10" seeing that's in progress -- ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Daniel Moisset added the comment: Fyi, I'm looking into the documentation. I think I can have something basic for the middle of this week, so it should be ok for March 1st. -- ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

Carol Willing added the comment: Absolutely, I can help do that. On Fri, Feb 19, 2021 at 9:14 PM Guido van Rossum wrote: > > Guido van Rossum added the comment: > > Carol, the most urgent thing we have going is to come up with text for > what's new. I posted a PR that adds my standard

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: Carol, the most urgent thing we have going is to come up with text for what's new. I posted a PR that adds my standard "quick" tutorial ( https://github.com/python/cpython/pull/24588) which is also found in Appendix A of PEP 636 (the tutorial PEP -- the

[issue42128] Structural Pattern Matching (PEP 634)

Carol Willing added the comment: @Brandt Bucher @Guido van Rossum I'm finally getting some free time to get the docs workgroup up and running. I'm happy to help with any docs that you want for alpha and beyond. On Fri, Feb 19, 2021 at 8:27 PM Guido van Rossum wrote: > > Guido van Rossum

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: But seriously, nothing good can come from social media. It's what drove me to retire in 2018. Just ignore it please. -- ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: Okay, I see. Clearly we should have kept the "DWIM" option, aka "If it starts with a capital letter, it's a value pattern." :-) -- ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

laurenjl added the comment: > I've seen too many knee-jerk reactions over the past weeks along the lines of > "the new switch feature can't handle named constants!". Here are some that I found interesting: https://twitter.com/jakevdp/status/1359870794877132810

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: Let's continue this at https://github.com/python/cpython/pull/24588 -- ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: I understand. I would just like to see something that won't give new Python pattern-matching users (read: everybody) the very painful first impression that this is a switch. Can we rework it like: match input().split(): case []: print("Got

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: > It's not a huge deal, but I vote that we either drop or rework the > "http_error" examples. I think it gives people a very wrong first impression > that makes the rest of the behavior quite surprising. > > Can it be changed to build off of something

[issue42128] Structural Pattern Matching (PEP 634)

Change by Guido van Rossum : -- pull_requests: +23368 pull_request: https://github.com/python/cpython/pull/24588 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: > Would people be okay if I added the tutorial from Appendix A of PEP 636 to > Doc/whatsnew/3.10.rst? Yes please! It's not a huge deal, but I vote that we either drop or rework the "http_error" examples. I think it gives people a very wrong first impression

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: I don't know who's really in charge of the docs. I suppose the PEP authors are, collectively, but that runs the risk that we're all expecting the person to our left in the circle to do it. Would people be okay if I added the tutorial from Appendix A of PEP

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: To the folks working on docs: Does it seem realistic to have something ready by the next alpha (March 1st)? I'd like to at least have a What's New entry and a rough draft tutorial by then, since we'll probably (hopefully?) have a bunch of users jumping on

[issue42128] Structural Pattern Matching (PEP 634)

Daniel Moisset added the comment: @Ken: I've invited you to the repo. For tracking the WIP, https://github.com/dmoisset/cpython/tree/patma-docs Do you want to see if you can base the reference/compound_stmts.rst changes in PEP 634? I'll try to fit a variant of the Appendix A of PEP 636 into

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Also, see my msg379831 above. We can't entirely rely on the PEPs, of course, but I think we could still get some decent reuse out of them. BTW, has the new docs WG started up yet? I keep hearing about it every once in a while, but I'm not sure if it's

[issue42128] Structural Pattern Matching (PEP 634)

Lysandros Nikolaou added the comment: The grammar is indeed auto-generated by reading the actual Grammar file, python.gram. Here's the lexer Pablo had developed for doing the syntax-highlighting. https://github.com/python/cpython/blob/master/Doc/tools/extensions/peg_highlight.py --

[issue42128] Structural Pattern Matching (PEP 634)

Ken Jin added the comment: Hi Daniel, wow thanks for the offer! My GitHub username is Fidget-Spinner. I'm not sure about the grammar file either. Oh, thanks for mentioning the tutorial recommendation by the SC, I'll keep that in mind.  -- ___

[issue42128] Structural Pattern Matching (PEP 634)

Daniel Moisset added the comment: Hey Ken, I was about to take on this myself, but I wouldn't mind a bit of help. Your list seems ok, I would add to it a section about PM in the python tutorial (which was explicitly mentioned in the SC acceptance notice). Regarding the grammar, I believe

[issue42128] Structural Pattern Matching (PEP 634)

Ken Jin added the comment: Guido and Brandt, may I take a stab at the docs for this? I'll probably base most of it off PEP 636's tutorial. Relevant parts of the docs that I've identified: reference/lexical_analysis.rst reference/compound_stmts.rst reference/grammar.rst # this probably needs

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: The PEP has been accepted. I propose that we use separate PRs for docs (and incremental improvements to the code) but tie them all together using the same issue number (this will require adding "skip news" to later PRs). --

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: I'll wait till the SC makes a ruling, then send a message to our docs list (I think we have one)? I'm fine coordinating/reviewing that, or making PRs myself if nobody else steps up. -- ___ Python tracker

[issue42128] Structural Pattern Matching (PEP 634)

Guido van Rossum added the comment: If you feel up to it, you might see if you could open a new, separate (draft) PR that updates all those docs. (But you could also wait and see if someone volunteers. There are some good doc writers active ATM.) --

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Thinking ahead... A lot of work has gone into writing these PEPs... we should see how much we can easily convert into actual docs. It seems to me: - Parts of PEP 634 and PEP 635 can be worked into the language reference. - Guido's overview (the appendix of

[issue42128] Structural Pattern Matching (PEP 634)

Change by Brandt Bucher : -- keywords: +patch pull_requests: +21846 pull_request: https://github.com/python/cpython/pull/22917 ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

Brandt Bucher added the comment: Sorry, just resolving some changes with master. Are you parser people finished breaking my grammar yet? Sheesh. ;) -- ___ Python tracker ___

[issue42128] Structural Pattern Matching (PEP 634)

New submission from Brandt Bucher : PEP 634 has not yet been accepted, but we'd like to hit the ground running and get this into alphas as soon as it (hopefully) is. Several people have volunteered to review the implementation, since it's so huge. Other reviews are very welcome, if anybody