Making ast.walk 220x Faster

I appreciate that you first tried to optimize the original Python code. Idiomatic Python is unfortunately disappointingly slow and not so interesting to compare to.

	▲	jerf 11 minutes ago \| parent [-]
		I often use the rough approximation that Python is 40-50x slower than C. This is what you'll see in the benchmarks. The truly rough thing about Python though is that that is the speed when the code is being written to a benchmark. It is really, really easy to write Python that is multiples slower than that when not writing to a benchmark and just trying to get work done without hyperoptimizing. I did some testing of Python [1] to back some other commentary I was making that compared the time it took to set an attribute repeatedly on a particular instance of an empty class to the time it took to setting it on a subclass of a subclass of a class that had a property setter that was wrapped by a decorator. The latter was about 4.6 time slower than the direct attribute setting, which was itself already ~100x slower than an attribute setting in a static language. And it's not like a three-deep nested class with a property wrapped by a decorator is all that absurd in Python or anything. That's a completely normal case, not some absurd example I made up to skew the test. In practice the 40-50x number is more lower bound than what you can count on. If you are actually using Python's features I think you can easily score another order of magnitude slower without anything jumping out at you as being an obviously bad idea. [1]: https://jerf.org/iri/post/2024/not_about_python_addendum/

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westurner an hour ago | parent | prev | next [-]

Could this ast.sprint ast.walk optimization make libCST or bandit faster? https://news.ycombinator.com/item?id=39111747

libCST: https://github.com/Instagram/LibCST

bandit: https://github.com/PyCQA/bandit

Links to codemod tools; "Baby Steps into Genetic Programming" https://news.ycombinator.com/item?id=43617655

	▲	adhami an hour ago \| parent \| next [-]
		it's possible! although many of the constraints in this blog were because we wanted to work with ast module in Python. If we were allowed to create our own types, we can do so much better. I think ruff has an even faster walk by those standards. It seems bandit is using some decent optimizations already, looking at the `@test.checks("Call")` seems like they already captured some easy wins. The largest win honestly would be using the same ast.walk for multiple rules, which we also did, but not mentioned in the blog.
	▲	westurner an hour ago \| parent \| prev [-]
		AST: Abstract Syntax Tree FST: Full Syntax Tree CST: Concrete Syntax Tree Comment preservation is a feature

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123rust123 an hour ago | parent | prev [-]

let me guess, the improved version is written in Rust?

	▲	adhami an hour ago \| parent [-]
		only because I'm too lazy to learn how to write C with Python, if anything Rust wasn't helpful with all of those unsafes