Python 3.10 refactor in the far-off future: Structural Pattern Matching

[God-damnit-all]

Normally I don't like to hop on the bandwagon for the latest Python, I tend to lag at least one or two versions behind while I wait for things to update, but Python 3.10 introduced a real game-changer in my opinion: Structural Pattern Matching

Or, in other words, the sort of switch-case statement that a ton of other programming languages have (though they don't actually use the word 'switch' in their implementation). Honestly, it's long overdue.

This article gives a more in-depth summary of its capabilities: https://towardsdatascience.com/more-advanced-pattern-matching-in-python-3-10-2dbd8598302a

Given all the different conditionals that go into every extractor, this seems like it would simplify things greatly. Worth noting that while it doesn't seem like it's possible to backport, the switch-case module could be a potential stand-in. It may be good to plan for the future.

[rautamiekka]

https://stackoverflow.com/questions/69710333/is-there-a-way-to-match-inequalities-in-python-%E2%89%A5-3-10

[God-damnit-all]

https://stackoverflow.com/questions/69710333/is-there-a-way-to-match-inequalities-in-python-%E2%89%A5-3-10

Uh, yes, that is what I'm talking about. Why are you linking me this?

[rautamiekka]

My point is SPM only supports equality checks officially, while inequality gets weird.

[God-damnit-all]

My point is SPM only supports equality checks officially, while inequality gets weird.

Does it have to be good at inequality checks? I was more thinking of parsing posts and needing to make a lot of different checks.

[rautamiekka]

If all the checks are always checking the equality (evaluates to True) instead of inequality (evaluates to False), it's fine. AFAICR, that's a tough thing to do in some places.

[mikf]

Sorry to disappoint, but I don't see this feature ever being used in gallery-dl, at least not while there are still people using Windows 7.

The last Python version that runs on Win7 is 3.8 and I plan on using that as the new minimum required version for gallery.dl v2 (currently it's Python 3.4). Language features not supported by that version therefore can't and won't be used, same as there are currently no f-strings and walrus operators in gallery-dl.

On a personal note, I don't really see the appeal of Structural Pattern Matching and why it needs 4 PEP documents (622, 634, 635, 636) for what are basically fancy if statements. Maybe I'm getting too old for all this new tech ...

the sort of switch-case statement that a ton of other programming languages have

There was a reason to use switch/case in C/C++ given how those were implemented in the resulting Assembly / machine code (ever heard of Duff's device?), but that hasn't been the case in most modern switch implementations, including Python's new match